Supreme Court New South Wales Medium Neutral Citation: Gales Holdings Pty Limited v Tweed Shire Council [2011] NSWSC 1128 Hearing dates: 15,17,and 21 February 2011; 2, 3, 4, 7, 8, 9, 10, 11, 14, 15, 18 March 2011; 4, 5, 6, 7, 8 April 2011 (written subs 10 May 2011) Decision date: 21 September 2011 Jurisdiction: Equity Division Before: Bergin CJ in Eq Decision: Nuisance established - plaintiff entitled to damages Catchwords: [NUISANCE] - stormwater runoff onto plaintiff's land - whether unreasonable interference with enjoyment of the land - land in undeveloped state - whether drainage inadequate and caused wetting up of the land causing harm with consequence of invasion of protected species of frogs [STATUTORY DEFENCES] - whether Civil Liability Act 2002 applies - whether defendant acted in good faith - whether defendant's conduct justified or excused [DAMAGES] - whether mandatory injunction or whether damages an adequate remedy Legislation Cited: Civil Liability Act 2002 Environmental Planning and Assessment Act 1979 Environment Protection and Biodiversity Conservation Act 1999 (Cth) Local Government Act 1993 National Parks and Wildlife Act 1974 Protection of the Environment Operations Act 1997 Roads Act 1993 Threatened Species Conservation Act 1995 Cases Cited: Bamford v Turnley (1862) 3 B. & S. 66 Bankstown City Council v Alamdo Holdings Pty Ltd (2005) 223 CLR 660; [2005] HCA 46 Brodie v Singleton Shire Council (2001) 206 CLR 512; [2001] HCA 29 Buckle v Bayswater Road Board (1936) 57 CLR 259 Cattanach v Melchior (2003) 215 CLR 1; [2003] HCA 38 Don Brass Foundry Pty Ltd v Stead (1948) 48 SR (NSW) 482 Duke of Leeds v Earl of Amhurst (1846) 2 Ph 117 Gales Holdings Pty Ltd v Minister for Infrastructure and Planning and Anor [2005] NSWLEC 617 Gales Holdings Pty Ltd v Minister for Infrastructure and Planning [2006] NSWCA 388 Gales Holdings Pty Limited v Tweed Shire Council [2006] NSWLEC 85 Gales Holdings Pty Limited v Tweed Shire Council [2006] NSWLEC 212 Gales Holdings Pty Limited v Tweed Shire Council [2008] NSWLEC 209 Hargrave v Goldman (1963) 110 CLR 40 Hill v Van Erp (1997) 188 CLR 159 Leakey v National Trust for Places of Historic Interest or Natural Beauty [1980] 1 QB 485 Melaleuca Estate Pty Ltd v Port Stephens Council (2006) 143 LGERA 319; [2006] NSWCA 31 Mid Density Developments Pty Limited v Rockdale Municipal Council (1993) 44 FCR 290 North Sydney Council v Roman (2007) 69 NSWLR 240; [2007] NSWCA 27 Orr v Ford (1989) 167 CLR 316 Overseas Tankship (UK) Limited v Miller Steamship Company Pty Ltd ("Wagon Mound (No 2)") [1967] 1 AC 617 Owners Strata Plan 4085 v Mallone (2006) 12 BPR 23,691; [2006] NSWSC 1381 Precision Products (NSW) Pty Ltd v Hawkesbury City Council (2008) 74 NSWLR 102; [2008] NSWCA 278 Pride of Derby and Derbyshire Angling Association Ltd v British Celanese Ltd [1953] 1 Ch 149 Quick v Alpine Nurseries Sales Pty Ltd [2010] NSWSC 1248 Roberts v Rodier (2006) 12 BPR 23,453; [2006] NSWSC 282 Robson v Leischke (2008) 72 NSWLR 98; [2008] NSWLEC 152 Sedleigh-Denfield v O'Callaghan [1940] AC 880 Southport Corporation v Esso Petroleum Co Ltd [1954] 2 QB 182 Sullivan v Moody (2001) 207 CLR 562; [2001] HCA 59 Sutherland Shire Council v Becker (2006) 150 LGERA 184; [2006] NSWCA 344 Sydney Water Corporation v Turano (2009) 239 CLR 51; [2009] HCA 42 Torette House Pty Ltd v Berkman (1940) 62 CLR 637 Victoria Park Racing and Recreation Grounds Co Ltd v Taylor (1937) 58 CLR 479 Walter v Selfe (1851) 4 De G. & Sm. 315 Willoughby Municipal Council v Halstead (1916) 22 CLR 352 Texts Cited: Clerk & Lindsell on Torts, 19th Ed. (Sweet & Maxwell, London) Dominic Villa Annotated Civil Liability Act 2002 (NSW) (2004, Law Book Co) Category: Principal judgment Parties: Gales Holdings Pty Limited (Plaintiff) Tweed Shire Council (Defendant) Representation: TF Robertson SC/M Green (Plaintiff) SR Donaldson SC/S Glascott/N Broadbent (Defendant) Allens Arthur Robinson (Plaintiff) DLA Phillips Fox (now DLA Piper) (Defendant) File Number(s): 2005/261912 Judgment 1The town of Kingscliff is on the Pacific Ocean coast in northern New South Wales. The Tweed River is to the west of the town and flows approximately parallel to the coast to meet the Ocean just north of the town. In the last thirty years Kingscliff has grown from a small beachside community to a well-developed seaside resort. Its inhabitants include both permanent residents and holidaymakers. Another inhabitant of the area is the Wallum Froglet, the endangered species Crinia tinnula , the presence of which has added complexity to the dispute between the parties to this litigation. Since 1974 the plaintiff, Gales Holdings Pty Limited, has been the registered proprietor of approximately 27 hectares of undeveloped land in Kingscliff (the Land) that is in the local government area of the Tweed Shire Council, the defendant. Background 2The plaintiff's claim against the defendant, described in detail later, is for damages in nuisance. Although the circumstances relied upon span more than 30 years, the nuisance alleged by the plaintiff is that since 1994 the defendant has conducted itself so as to cause or allow untreated and polluted stormwater runoff to discharge directly and indirectly via the defendant's closed pipe system, roads, kerbs and gutters and the stormwater outlets from the local catchments onto the Land and to prevent and obstruct stormwater passing and flowing away from the Land. It is not seriously in issue that since 1994 there has been an increase in the amount of stormwater runoff flowing onto the Land. However the parties are at issue in relation to a number of the specific claims the plaintiff makes against the defendant (referred to later) and in particular whether the presence of the stormwater runoff on the Land constitutes a nuisance. 3The plaintiff claims that one of the foreseeable consequences of the increase in the levels of stormwater runoff on the Land as a result of the defendant's conduct was the occurrence of ephemeral ponding of water for periods that would result in the establishment of a habitat suitable for Wallum Froglets with the foreseeable further consequences that the Wallum Froglets would be attracted to and breed in that habitat and that the plaintiff would lose that portion of the Land for development and have to bear the burden of maintaining a habitat for the Wallum froglets. The expression "Wallum Froglet habitat" has been used in differing ways in the proceedings. It has been used to describe the physical home or habitat of the Wallum Froglet. It has also been used to describe the mix of vegetation and other environmental factors, including ephemeral ponding, to which Wallum Froglets are attracted to live and breed. The Land 4The Land is within the green boundary line in the photograph in Schedule A (Ex A) to this judgment. Turnock Street dissects the Land and the issues in the proceedings have been addressed by reference to parts of the Land being either to the north or the south of Turnock Street. Pearl Street and Kingscliff Street are to the east of the Land and Quigan Street is to the south of the Land. Turnock Street meets Elrond Drive to the west of the Land at a roundabout. Elrond Drive runs in a north-westerly direction along the south western corner of the Land north of Turnock Street. The western boundary of the Land north of Turnock Street abuts the eastern boundary of a housing estate known as "Noble Park Estate" (NPE). The northern boundary of NPE is relevant to what has been referred to as the "Northern Drain". To the north of the Land are properties referred to in the proceedings as the "Nursing Home" or "Nursing Association" and the "Bowls Club". 5Prior to the 1990s the drainage of the Land and of the Kingscliff area generally was as depicted in Schedule B (Ex B) to this judgment. Stormwater drained from the Land to the Tweed River via the Northern Drain, the Eastern Drain, the South Westerly Drain, the Natural Watercourse and the Chinderah Drain. 6The Land is zoned 2(c) under the Tweed Local Environmental Plan 2000 (LEP 2000), the primary objectives of which are to identify land for urban expansion and to ensure its optimum utilisation consistent with environmental constraints and the need to minimise residential landtake. The secondary objectives of LEP 2000 are to allow associated non-residential development to ensure that sensitive environment areas within the Zone are protected from adverse impacts of developments and to enable planning flexibility to achieve the other objectives of the Zone by means of detailed guidelines in a development control plan. One of the objectives of LEP 2000 is to "promote development that is consistent with the four principles of ecologically sustainable development" identified as: the precautionary principle; inter-generational equity; conservation of biological diversity and ecological integrity; and improved valuation, pricing and incentive mechanisms. 7The defendant is able to grant consent to development only if it is satisfied that it is consistent with the primary objective of the Zone within which the proposed development is located; if it has considered those other aims and objectives of LEP 2000 that are relevant to the development; and if it is satisfied that the development would not have "an unacceptable cumulative impact on the community, locality or catchment that will be affected by its being carried out or on the area of Tweed as a whole". 8The Land was first acquired by Dr Harry Segal (a director and controlling shareholder of the plaintiff) and his wife in 1969. It was transferred to the plaintiff in 1974. Dr Segal's son, Stephen Segal, has been a director of the plaintiff since 1977 and assumed the management of the Land from the late 1990s. 9The Land was cleared of large vegetation in the 1970s and subsequently used for grazing cattle until the 1990s and thereafter for agistment of horses. During the period from the 1970s through to the late 1990s Dr Segal walked over the Land from time to time to check on the cattle and/or the fences. At other times he would observe the Land from the top of the hill south of Quigan Street from which he could see the whole of the Land. Dr Segal was never restricted from walking over the Land by any flooding nor did he observe it to be overly moist, except for one area below the Kingscliff hill on the south eastern edge of the Land near Quigan Street. 10The plaintiff read a number of affidavits of witnesses who had made observations of the Land during the period from 1970 to the late 1990s. That evidence was unchallenged. Between the 1970s and the early 1990s Peter Gray managed cattle on the Land and accessed it generally on horseback but also by foot, tractor and utility. His evidence was that he never experienced vehicles being bogged nor did he observe any inundation of water except after certain flooding events. After a flooding event the water level always returned to normal, meaning that the drains on the Land were between approximately half and three quarters full, depending on the tide. Mr Gray observed that the vegetation was the same as the vegetation on surrounding land. It was mostly low-lying scrubby vegetation such as bottlebrush and small trees. 11Between 1971 and the 1990s Verlie Moodie walked on the Land regularly to collect cow manure for her garden and/or for leisure and exercise. Mrs Moodie's evidence was that the Land was a large open space with a few scattered trees. After rainfall some of the Land was damp and moist but it was never sludgy or drenched with water. Mrs Moodie could not recall any occasion on which the Land was ponded or submerged with water. 12In 1978 Gil May travelled on an "east/west road to the main Chinderah north/south drain". He then "went into a small boat, a duck punt", up a drain "which went east/west". He went up that drain "about third of a kilometre". Mr May referred to this drain in his evidence as the "northern east/west drain". He described it as a natural watercourse that had been dug to make it deeper. It was about 2 to 3 metres wide when full of water and about 1.5 to 2 metres deep in a king tide. The banks of the drain were covered in grass, sedge and native plants. It was lined with mangroves near the intersection with the Chinderah Drain. The last time Mr May went fishing in the northern east/west drain was in 1991 when it was in much the same condition as in 1978. The water in the drain was at least waist deep. There was no cross-examination of Mr May and it is probable that the northern east/west drain that he described in his evidence is the Northern Drain. 13Mr May observed acacias on the north eastern side of Lots 11, 12 and 13 of the Land. There was a wet patch in Lot 12 north of where Turnock Street was later constructed in which Mr May observed that there was a two to three metre section with a sandy bottom where the water would go up to "just below your knees". Mr May observed that it was a natural depression and was grazed by cattle with clusters of small trees and patches of sedge. 14Catherine Boyd who has lived in Pearl Street, Kingscliff since the 1950s gave evidence of observing cattle grazing on the Land from the 1970s to the 1990s. Mrs Boyd walked over the Land during that period on a weekly basis for "leisure". Mrs Boyd did not observe any parts of the Land being "wet, flooded or submerged". She observed wallabies and kangaroos and "lots of" small trees. Mrs Boyd also gave evidence that about once a year, the local fire brigade would practice their fire management skills on the Land. 15Reginald Goodwin worked on the Land in 1990 and 1991 spraying herbicide on groundshell bush in Lot 10. Mr Goodwin brought a tractor and spraying equipment (that together weighed approximately 6 tonne) in the back of an 11 tonne tip truck which he drove through the Land. He then unloaded the tractor, completed the spraying and loaded the tractor back onto the truck and drove back through the Land. Mr Goodwin said that the ground was "rock solid" and he never had any trouble with the truck or the tractor becoming bogged. At this time he observed approximately 30 horses on the Land. 16After the construction of Turnock Street in 1997 Mr Goodwin returned to the Land and began "slashing" the Land both north and south of Turnock Street. He slashed the Land at least once a year. Since the construction of Turnock Street the tractor "got bogged continuously". Mr Goodwin had to use two tractors, "one tractor to pull the other tractor out", because the Land is "so soggy now". Mr Goodwin noticed that after the construction of Turnock Street the vegetation in Lots 11, 12 and 13 of the Land had become thicker with "more reedy types of grass". Early drainage problems 17On 31 July 1974 Dr Segal wrote to the defendant advising that he felt that the defendant must accept responsibility for the large drains which "open directly" onto the Land that were "causing severe localised drainage problems". 18On 4 August 1974 Les Noble of Les Noble Pty Limited, Auctioneers, Real Estate Agents and Valuers, owner of the adjoining property to the west of the Land, wrote to Dr Segal in the following terms: The so-called swamp on your property, which is at the back of our property, is only brought about by the fact that the now existing drains in the property have never been cleaned out for the past twenty years and if you feel like doing that, also in the new part, it would improve it immensely. 19On 27 August 1974 the defendant wrote to Dr Segal in response to his letter of 31 July 1974 and advised that the defendant did not "at present" have sufficient funds to consider drainage through the Land. That letter included the following: Whilst it is accepted that drainage from Kingscliff streets discharges onto the property, the area, of course, is a natural water course or collection area. The matter may be further considered when development proposals in the areas are considered. 20On 5 November 1974 Mr Noble wrote to Dr Segal advising him of his recent discussions with some drainage contractors and suggested that Dr Segal spend up to $600 on drainage. On 3 December 1974 Mr Noble advised Dr Segal that he had engaged the drainage contractor and that when the work was completed "you will be looking at a different property". Dr Segal gave affidavit evidence that he did not understand why it was that Mr Noble used the expression "swamp" in his correspondence to describe the Land. Proposal to develop the Land - 1978 21In 1978 the plaintiff submitted a proposal to develop the Land. The defendant advised the plaintiff that detailed flood and environmental studies would have to be completed. The plaintiff offered to contribute to the cost of the flood studies, however in December 1978 the defendant advised the plaintiff that funds had been allocated for such studies and it would not be necessary for the plaintiff to contribute to the cost of them. Growth Plan 22In 1980 the plaintiff instructed Burchill & Partners Pty Limited, Consulting Engineers and Planners, to provide a report in respect of a proposed "Growth Plan" for Kingscliff. That proposal was to develop not only the Land but also Mr Noble's property. The report noted that the Land was subject to "inundation in the 1:100 flood in the Tweed River System, to a depth of average 2.0 metres" and that up to that time it had been omitted from planning for new development for that reason. The report included the following: If a practical and economically viable method can be found of overcoming the flood factor, by filling and draining, then the land would be available to serve the desired use as the preferred future development zone for Kingscliff. 23The report also noted that the combined area of the properties was approximately 75 hectares, about one half the area of the then existing township. It also noted the demographic phenomenon of increasing migration from major cities to provincial coastal towns with the most desirable climates and environments and it was suggested that Kingscliff would attract an overspill of the growth element in the Gold Coast. The report also noted that there was too little existing stock and it was essential to stimulate new development rather urgently. The report made reference to the Draft Tweed Coast Plan and included the following: The Draft Tweed Coast Plan showed that there were no flora and fauna species on our clients' lands which require or warrant protection. 24The Burchill & Partners report was submitted to the defendant. The defendant advised the plaintiff that it had considered the proposal for the Growth Plan at its meeting on 17 December 1980 and had resolved to prepare a draft Local Environmental Plan. It also advised that a detailed report was required on the effect of excavating and filling the flood plain and that an environmental assessment needed to be made of the impact of the proposed artificial lakes that formed part of the Growth Plan. 25On 12 March 1981 the defendant advised the plaintiff that it was necessary for the Growth Plan to demonstrate how flooding would be overcome "including the determination of pumping or other facilities necessary to remove local stormwater from within the protected area" and to identify the drainage paths of existing Kingscliff urban development and the effect of the proposed works on such existing usage. It is not clear to what the expression "protected area" referred but it was not suggested that it has any significance to the issues in this litigation. The plaintiff met with the defendant during 1981 and was advised more than once that "not a grain of sand can be moved until drainage studies are done and these drainage studies permit filling to occur". 26Between the early 1980s and the early 1990s the Land was not developed nor was the Growth Plan adopted. However it is apparent that the defendant worked on developing a draft Development Control Plan. Cessation of cattle grazing 27Some time in the 1990s the plaintiff discontinued grazing cattle on the Land because of reports of the presence of a pack of dogs that were killing newborn calves. There were also reports of vandalism on the Land. Subsequently the plaintiff made a decision to permit the agistment of horses on the Land. Development Consent to NPE - December 1992 28On 9 December 1992 a Development Consent was issued to Baclon Pty Ltd (Baclon) for the development of Mr Noble's land to the west of the Land into the NPE. The proposed development included the construction of a lake to the west of NPE and west of Elrond Drive. The Eastern Drain (on the boundary between the NPE and the Land) was to be filled in and a batter wall was to be created onto the western boundary of the Land. 29The conditions to the Development Consent included the following: 36. The proposed subdivision is to be filled to RL 3.5m AHD in accordance with the approved plans. ... 40. The Engineer Drainage Design plans shall address the 5 year discharge from the ultimate fully developed upstream contributing catchment and any foreshadowed development in upstream catchment which will contribute to the runoff through this development. ... 43. A drainage overflow path to accommodate Q 100 flows shall be retained along the northern boundary of the land until such time as the drainage strategy is resolved. Details to be shown on the engineering plans. 30The drainage overflow path along the northern boundary referred to in condition 43 to the Development Consent was necessary because one of the streets in the NPE, Lorien Way, was to be extended across the Northern Drain. Murray vegetation mapping -1992 31In June 1992 Andrew Murray, a botanist and vegetation ecologist, surveyed the Land as part of a comprehensive fine scale vegetation mapping project for coastal lands in the Tweed Shire. Mr Murray observed "shallow standing water" over a large part of the Land at this time. DCP 9 - 1993 32The Tweed Development Control Plan No 9 (DCP 9) (which applies to the Land) came into force on 7 October 1993. Its purpose is, inter alia , to provide detailed guidance to developers within the area and to indicate the defendant's policies with respect to development in the area. Matters pertinent to this litigation in DCP 9 include: (1) A water quality report and water quality monitoring program is required for all applications for filling and subdivision; (2) Filling of land for residential development is to be 3.4m AHD; and (3) Applications for filling are to include information demonstrating that fill will have no adverse effects on flooding or drainage characteristics of nearby land. DCP 9 also includes a section entitled "E. Drainage & Water Quality Management", the objectives of which include the prevention of "flooding and stormwater damage to the built and natural environment". It is noted in the DCP that subdivision applications will be refused unless it is "proved that the land is capable of development without adverse effects on flooding or drainage elsewhere". 1994 complaints 33Baclon's consulting engineers for the NPE development were Martin Findlater & Associates Pty Ltd. On 15 March 1994 Mr Henley of the defendant met Mr Findlater to inspect the work at NPE. In a note made of that meeting on 17 March 1994 Mr Henley wrote: I am not very happy with the connection from the end of new works to the old drain. I have agreed with Martin Findlater outflow improvements may be able to await the moving of machinery on site for next stage. Either the outlet drain is to be widened or the overland flow path is to be cleared and levelled. This could be considered as part of maintenance but I advised Martin that if we have any problems I will require that he immediately complete improvements to the outflow channel. 34On 21 April 1994 the consulting engineer for the Bowls Club, Ian Hill of Ian Hill & Associates Pty Limited, wrote to the defendant advising that he acted for both the Bowls Club and the Nursing Association and that he had recently inspected the rear of properties north of NPE. The letter included the following: The temporary diversion drain, that was constructed around the subdivision at the time of the lake construction contract, has been filled in as has also the union drain that followed the east-west boundary within the Noble Park property. A recent inspection revealed that water is ponding along this latter boundary line, and little cognisance appears to have been taken of the upstream catchment of Pearl Street, Kingscliff Street, the land between these streets and the subdivision. 35Mr Hill advised that he had spoken with Mr Findlater and requested the engineering drawings so that he could make an assessment of the position. On 27 April 1994 the defendant wrote to Mr Hill and requested that he liaise with Mr Findlater in relation to the resolution of any future problems. 36On 17 June 1994 Mr Hill wrote again to the defendant advising that he had completed the investigation of the drainage at the rear of the properties and reported as follows: We do not believe that it is this firm's responsibility to resolve the problem as the works associated with the subdivision, which clearly prejudice our Client, were approved and supervised by Council. You are aware that Council's drainage, from Kingscliff and Pearl Streets, discharge onto the Club property and this was extended at the Club's cost, with no assistance from Council, across the property to the open drain that ran along the northern boundary of Baclon Pty Ltd property to the Kingscliff union drain. This drain is shown as lateral Drain B in the draft report on Kingscliff Drainage Strategy prepared by WBM Oceanics Pty Ltd and, with Council's permission, has been filled in by Baclon Pty Ltd. We would appreciate advice as to what remedial action will be implemented before the start of the next wet season. Warren Report - 1994 37In mid 1994 the plaintiff had applied to the defendant for approval for clearing operations to be carried out on the Land in areas that were covered by a Tree Preservation Order. In June 1994 James Warren, a biological and environmental consultant, provided a report to the plaintiff entitled " Flora and Fauna (Section 4A) Assessment ". An assessment under s 4A of the Environmental Planning and Assessment Act 1979 (NSW) (the EPA Act) determines whether a development will have a significant impact on endangered fauna or their habitat. Mr Warren noted that the Land was still being utilised for horse and/or cattle grazing purposes and he identified a Paperbark forest and a "clump of Wallum bottlebrush" in the southern portion of the Land. Mr Warren referred to a computer check on the local records that had been carried out by the National Parks & Wildlife Service (NPWS) that had identified significant threatened species recorded in the locality. He observed that a number of endangered species "might also be expected to occur in the locality". Although there was mention of the Wallum tree frog ( Litoria olongburensis ), there was no mention of the Wallum Froglet. That survey included the following: The sites, due to their highly disturbed nature are likely to contain high numbers of Cane toads. These amphibians displace native frogs and are even thought to feed on small native frogs. It is possible, though unlikely, that the site contains Wallum frogs. If the frogs occur it is most likely that they would occur in the perennially wet areas associated with the Paperbark forests. 38The Wallum Froglet is a "vulnerable species" under the Threatened Species Conservation Act 1995. It first attained a protected status in 1992 when it was listed as a "Vulnerable and Rare Species" in Schedule 12 of the National Parks and Wildlife Act 1974. If a proposed development would significantly affect a threatened species, the EPA Act requires a species impact statement to be prepared before the application may be considered. The impact of the development on the threatened species must be assessed when determining the development application. It is an offence under section 118A of the National Parks and Wildlife Act for a person to harm any "threatened species" (which includes a "vulnerable species"). WBM Oceanic - 1994 39On 10 August 1994 WBM Oceanic Australia (WBM), commissioned by the defendant, produced the "Kingscliff Drainage Strategy Plan" (Ex O) (the WBM Report). The WBM Report documented the development of the drainage strategy for major flooding of the Kingscliff area. It recorded that the need for the Plan had arisen "due to the degree of urbanisation and filling planned for the catchment". Figure 1.1 of the Plan entitled "Kingscliff Drainage Catchment" showed a "Catchment Boundary" that is also depicted in Schedule A to this judgment by the yellow boundary line. WBM reported that the development of a "stormwater drainage strategy plan for the Kingscliff drain" in Figure 1.1 was in accordance with the Development Control Plan No. 9 (DCP 9) for the West Kingscliff area. Ian Hill & Associates Report 40On 14 September 1994 Mr Hill provided the defendant with a copy of a report prepared by his firm entitled "Drainage of Kingscliff Street Site". That report included the following: 3.0 DRAINAGE PATTERNS - 1993 During 1993, the subdivision known as Noble Park Estate was constructed; part of construction involved filling of the site by some 2 m, during which the open drain was filled in and the filling extended across into the Club's land without any further discussions with the Club and without the Club's approval. At a brief inspection of the Bowls Club site, in February 1994, Mr Hill of this office noted that the drainage path was blocked by filling, including the filling for a roadway from the adjacent Middle Harbour development. Mr Hill rang the Tweed Council and spoke to Mr John Samuels, voicing concern that no provision had been made for drainage of the land to the north and east of the Baclon development, and was advised that the blockage was only temporary. An inspection in March 1994, showed that the subdivision filling had been completed; no allowance was made under the roadway for escape of stormwater, and a 1200mm dia concrete pipe had been provided at the corner of the Bowls Club property, which was supposed to carry the stormwater to the west and north of the subdivision. 41The report concluded that the 1200mm height was "under capacity" for the Q5 event (being a storm event of a magnitude that occurs on average once every five years) and no provision had been made for the Q100 event; that the design ignored the defendant's drainage strategy for Kingscliff; that the installed drainage system had not been constructed as designed, further reducing the capacity of the system to cater for stormwater runoff; and that as a result, the properties of the Bowls Club and Nursing Association would be subject to a greater degree of flooding than would have occurred prior to the construction of NPE. 42After the defendant received the report from Mr Hill and a further letter from the lawyers for the Bowls Club it wrote to Martin Findlater on 31 October 1994 expressing its concerns regarding the Q5 hydraulic capacity of the 1200 diameter pipe and the resulting potential for flooding of adjoining property owned by the Kingscliff Bowls Club. The defendant referred to the WBM Report that indicated a catchment larger than that adopted by Mr Findlater in his design and suggested that this "discrepancy should be clarified". 43On 2 February 1995 the defendant wrote to Mr Hill advising him that it had recently held discussions with Mr Findlater "in an attempt to formulate a solution to the problem". The defendant advised that as a result of the meeting it was agreed that Mr Findlater would "submit a number of options" for the defendant's consideration, which it was still awaiting. Retention Basin Proposal - March 1995 44At this stage Baclon was seeking approval for the fourth stage of the NPE development from the defendant. On 1 March 1995 the defendant advised Mr Findlater that no further approvals or consents would be given "until the drainage solution and its funding is agreed upon". That letter included the following: Given that your original stormwater design did not adequately cater for the Q100 storm event and that Council has no funds for such analysis at this stage, it is intended that Council initiate the analysis at the consultants cost. 45On 2 March 1995 the defendant wrote to Mr Findlater in terms that included the following: The Panel also resolved that any fresh development application will not be determined until the upstream drainage issues are resolved because the approved Part 12 application causes inundation of properties in excess of permissible levels. 46On 9 March 1995 Mr Findlater wrote to the defendant referring to verbal advice from the defendant on 8 March 1995 that permission to complete the drainage work through NPE Stage Four would be approved upon the condition that Baclon Pty Ltd requested the defendant to amend DCP 9 and the Section 94 Plan for West Kingscliff. That letter included the following: In accordance with your instructions we suggest the DCP 9 be amended as follows: A nominal area of 1 Ha for future multi-purpose open space/flood retention/wet land filter should be reserved east of Noble Park estate. The value of the land shall be incorporated into the drainage and S94 Plan and reimbursed from that plan. Any open space component shall be credited against the passive or active open space requirements for development in the area as appropriate to the use of the land. Our client is offering this suggestion as an alternative to the proposed 20m wide open channel adjacent to the northern boundary of Noble Park estate. That proposal formed part of WBM Oceanics Kingscliff Drainage Strategy Plan report dated August 1994. Calculations demonstrating the feasibility of the alternative have been supplied to Mr Henley. 47Although Mr Findlater did not expressly refer to it, the proposal to put aside an area of one hectare east of NPE was really a suggestion that the Land be used as a retention basin. 48On 10 March 1995 Mr Findlater wrote to the defendant in answer to its letter of 1 March 1995 refuting the assertion that the original stormwater drainage design did not adequately cater for the Q100 storm event. That letter included the following: The drainage for the estate was designed and constructed in accordance with Council's Development Consent for the estate. This is confirmed by the approval of the layout plan, the engineering drawings and the release of the linen plan of subdivision. Council has now developed a drainage strategy for Kingscliff which is reported by Council's consultant WBM Oceanics. That drainage strategy (dated August 1994) incorporates specific water level controls which were not required under the consent and are a consequence of the study. To achieve those controls the strategy provides for an open drain at least 20m wide adjacent to our clients northern boundary. Our client is concerned about the practicality of such a drainage ditch. He is also concerned that piped alternatives are expensive and would unnecessarily increase Section 94 Contributions. We have provided objective alternatives to the drainage strategy and identified corrections that should be made to the model. This work has been carried out at no cost to Council. We are disappointed that Council should consider our comments as an implication that Noble Park drainage is deficient. Our client has been required to supply work in kind to the value of $586,000. This is for a S94 liability for approved development of less than $200,000. Our client does not intend to provide additional funding other than what is required as a result of reasonable variations to the S94 Plan. Such variations can be adjusted in credits due. We also confirm that we shall not be contributing to any additional analysis by Council to determine alternatives to their drainage study. We understand from discussions with Mr J. Henley that this will not be required. 49On 13 March 1995 the Manager Subdivisions of the defendant wrote to the Director Development Services of the defendant in terms that included the following: As you will recall, following completion of the early stages of Noble Park Estate it became apparent that a drainage problem existed in relation to the existing developed land upstream of the estate. Following rainfall, complaints were received from residents; Ian Hill on behalf of the Blue Nursing Service and the Bowls Club in relation to inundation of their properties. Investigations and discussions between Council officers and Martin Findlater, (consultant for Noble Park) have been continuing for some months, however as the matter had not been resolved, no further consents/releases have been issued for West Kingscliff for about 3 months. Following further discussions on 7 March 1993 between John Henley, Col Dutton and Martin Findlater, a possible solution was agreed to in principle. That concept involves: 1. A detention basin in Dr Segals land adjacent to Noble Park Estate; 2. Possible "joint use" of the basin as a water quality control pond; 3. Possible "joint use" of the basin/pond for recreation purposes (ie. passive open space). To allow for this concept to be formally considered the following approach has been agreed: 1. Martin Findlater will make a formal request to amend Development Control Plan No. 9 and the Section 94 plan (if necessary) to facilitate the proposal; 2. The written approval of Dr Segal, will accompany this request; There is a high degree of urgency in finalising the Development Control Plan amendments having regard to the interests of Council and the community and therefore it is recommended that processing of the matter be given a high priority. 50On 15 March 1995 the Strategic Town Planner of the defendant wrote to the Director Development Services of the defendant in terms that included the following: The land on which the detention basin is proposed is nominated for medium density housing in the DCP and I think it is highly unlikely that Gales Holdings would agree to its use for any other purpose. ... I am concerned that a 'quick fix' of the current drainage problem may have implications for drainage and development in the rest of West Kingscliff which has not been evaluated. 51On 23 March 1995 the defendant wrote to the plaintiff in the following terms: DCP No. 9 - West Kingscliff Following preparation of the Kingscliff Drainage Strategy Plan and investigation of drainage issues it is proposed to recommend to Council that the above DCP be amended as follows: 1. To allow for the provision of a stormwater detention basin of about 1 ha within land owned by Gales Holdings Pty Limited adjacent to Noble Park Estate, generally as indicated on the attached map; 2. To enable the possible "joint use" of the basin as a water quality control pond and passive recreation area. 52The plaintiff had retained town planners, Outline Planning Consultants Pty Limited of which Mr Gary Peacock was a director, to assist it with reviewing DCP 9. On 5 May 1995 the defendant wrote to Mr Peacock advising that it wished to work closely with him in reviewing DCP 9. The defendant conceded that DCP 9 required significant review and accepted that Mr Peacock's proposal that a steering committee or working group be established was a positive and sound approach and that he would be invited to participate in such committee or group. Mr Peacock met with the defendant's officers on 30 May 1995 in relation to the roads and drainage infrastructure needs of the West Kingscliff area and their likely impact on the Land. On 22 June 1995 the Council wrote to Mr Peacock advising that it may be possible to reduce the area of the Land affected particularly in relation to drainage and water quality needs. The defendant advised that it could only make an assessment if it had "full knowledge of the future plans" that the plaintiff had for the Land. 53The plaintiff, through Outline Planning Consultants, also retained Ray Sargent, a Civil and Structural Engineer, to assist it with assessing the defendant's proposal for the retention basin to be situated on the Land. Mr Sargent met with an officer of the defendant, John Henley, an engineer, in September 1995 and undertook a detailed inspection of the Land for the purposes of assessing the drainage aspects of the Land. DCP 9 to be amended 54On 27 September 1995 the defendant resolved to prepare an amendment to DCP 9 and Contribution Plan No 7 relating to West Kingscliff. In a Council report in support of the resolution it was noted that it had become apparent after the completion of the early stages of NPE that a drainage problem existed in relation to developed land upstream of NPE. It was noted that "a possible solution" involved the construction of a detention basin on the Land and that Baclon had no objection to the proposal. That is hardly surprising having regard to the fact that the proposal imposed all the burden on the plaintiff for the drainage problems created by Baclon's development. The report concluded that the way in which to resolve the drainage problem promptly was to prepare and exhibit amendments to DCP 9 and to make further efforts to obtain the plaintiff's views during the exhibition period. 55An internal memorandum of the defendant dated 1 November 1995 records that any further action on the detention basin was to be held in abeyance. It was noted that the plaintiff was "now aware" of the need for a detention basin and the DCP 9 amendment process could be delayed provided that everyone remained aware of the location of the proposed detention basin. It was also noted that if the plaintiff sold the Land there was no mechanism for ensuring that any future owner was aware that one hectare of land should not be filled and should remain available for drainage retardation. 56On 2 November 1995 Mr Hill, who by that stage had moved to another firm, Cardno & Davies, wrote to the defendant noting that he had heard nothing in the nine months since he had been advised that the defendant was seeking a number of options from Mr Findlater towards solving the drainage problems. The defendant responded by letter dated 18 December 1995 advising that "agreement has been reached" with Mr Findlater "for the creation of a stormwater/flood retention basin adjacent to the culvert in question". There was no mention of the fact that the proposed retention basin was on the Land rather than on NPE. Nor was there any mention of the fact that the plaintiff had not agreed to the retention basin. 57Mr Peacock had been communicating with the defendant in October 1995 in relation to the proposed amendment to DCP 9. On 23 November 1995 the defendant wrote to Mr Peacock advising that there would be no immediate action to proceed with the draft amendment to DCP 9 and observing that as the plaintiff was now "formally aware" of the need for a retention basin it would be necessary to obtain a formal assurance that a prospective purchaser of the Land would be notified that one hectare of the Land should not be filled and had to remain available for drainage retardation. There is no evidence that the request for such a "formal assurance" was ever pursued further or given. Plans for Turnock Street 58It was in late 1995 that the defendant proposed constructing a distributor road that was later to become Turnock Street. It was agreed between the parties that the defendant would make a direct purchase of a portion of the Land at an agreed valuation or provide a credit against future contributions levied against development on the Land under the EPA Act. The defendant had to comply with section 111 of the EPA Act and consider whether the construction of Turnock Street would require an environmental impact statement (EIS) under section 112 of the EPA Act and what other impacts it would have on the environment. The defendant advised the plaintiff that it wished to proceed with an environmental assessment of the proposed activity and requested from Mr Peacock the results of any studies previously undertaken on the site. In late December 1995 the plaintiff provided its consent to the defendant to enter the Land for the purpose of carrying out site survey work associated with the proposed road. 59Mr Peacock provided a copy of Mr Warren's June 1994 report to the defendant to assist it with its assessment of the Turnock Street extension. In March 1996 Woodward-Clyde, consulting engineers, put a proposal to the defendant to carry out flora and fauna assessments of the Land including the carrying out of an amphibian survey utilising "call recording and analysis". Woodward-Clyde advised that the call analysis was to be undertaken by an officer of the Queensland Museum and that the frog survey could be most effectively carried out between August and March during rainfall to ensure maximum species identification. Woodward-Clyde Report - May 1996 60In May 1996 Woodward-Clyde produced their report entitled "Flora and Fauna Assessment of a Proposed Road Deviation". The report referred to NPWS records that indicated that certain threatened faunal species could occur either on the site or nearby at various times including both the Wallum Froglet and the Wallum tree frog. The report recorded that sampling efforts had attempted to detect the widest possible range of species utilising a range of methods including call identification, direct observation, Pitfall traps (buckets and drift fences) and Elliott traps. The report included the following: Neither the Wallum froglet nor Wallum treefrog were recorded during site surveys. Gilmore et al (1986) indicates that both species are particularly sensitive to the alteration of water chemistry and are found only in oligotrophic waters. However, WWC (1995) have recorded the Wallum froglet in a piggery effluent drain suggesting that it is perhaps more adaptable than previously thought. The Wallum froglet was considered most likely to occur along the drain to the south of the roundabout where a number of other frogs were recorded. 61Appendix 3 to the Woodward-Clyde report noted that the Wallum Froglet was not recorded during site surveys but that it "may be present" in a drain south of the study area. Appendix 3 also recorded that the effect of the development on the life cycle of the Wallum Froglet was minor in respect of breeding and foraging and there was a nil effect on the migration/movements of the Wallum Froglet. 62On 29 July 1996 Ray Sargent & Associates (at this time retained by the defendant) wrote to the defendant enclosing a number of plans showing the "major drainage outlet points for the Turnock Street/Elrond Drive area". Those documents illustrated the situation after the construction of the roadworks "and future site filling works". That letter included the following: (1) After construction of the deviation road, the low lying areas to the north of the road will drain through outlet 2. This outlet is to be sized to drain the selected design storm over the catchment without causing flooding to existing developed areas. The catchment area is the total of the areas marked A, B, C, D & E (41.64ha). (2) Area E will ultimately drain to the future open drain and outlet labelled 7 as per DCP No. 9. As the embankment of Lorien Way currently blocks this path, Catchment E needs to be temporarily drained through outlet 2 until the outlet at 7 is opened. ... (6) Outlet 2 would become redundant if the ultimate scheme is implemented as shown. The design of outlet 2 is indicated on the attached Sketch SK1 and has been based on limiting headwater to a level of 2.1m AHD to avoid flooding of the existing surface level of the proposed Bowling Club for the design event. To compare the culvert sizes detailed below are culvert sizes for 1:100, 1:20 and 1:5 year events: 1:100 3 x 1500 dia 1:20 3 x 1200 dia 1:5 2 x 1050 dia ... Please advise if the above scheme is acceptable to Council so that the drainage design for the proposed roadworks can be finalised. 63The plan attached to the letter, "SK 1", referred to the total catchment area north of Turnock Street as 41.64ha and recorded that three 1500 millimetre pipes would be at point 2 on SK 1. Point 2 on SK 1 is in the area that the Elrond Drive culvert (referred to later) was constructed. The three pipes as suggested in SK 1 were not constructed in that location. The plaintiff submitted that despite the fact that the defendant knew that the Elrond Drive culvert had a catchment area of 41.64ha and required three 1500 millimetre pipes to pass water under that culvert to drain that area, it did not provide three pipes to do so (tr 142). 64On 9 August 1996 Ray Sargent & Associates (at this stage retained by the plaintiff) produced a report entitled " Proposed Stormwater Quality Improvement Scheme for West Kingscliff, Tweed Shire" . That report proposed that a "first flush runoff system" be instituted to catch the first flush of runoff from the catchment and retain it in ponds for a sufficient time for the water quality to be improved prior to discharge. The report concluded that the treatment of stormwater runoff in this way would improve the quality of the final downstream water outflow by up to 50%. It also included the following: This will be a significant improvement on the existing drainage system which contains no formal structures for removing contaminates from runoff apart from sedimentation action within the main drains. 65On 23 August 1996 the plaintiff provided its consent to the defendant's development application for the proposed Turnock Street extension. Follow up of 1994 complaints 66On 3 September 1996 Mr Hill resumed communications with the defendant in relation to the problems that he had identified with the 1200mm pipe where the Northern Drain was previously located. He wrote to the defendant on that date advising that he had not had any further information as to the location, sizing or time of construction of the proposed retention basin referred to in the defendant's letter to him of 18 December 1995. Mr Hill advised that a recent inspection showed the inlet to the 1200mm pipe to be restricted by weed growth. He also suggested that with the approach of the wet season his clients (the Bowls Club and the Nursing Home) were concerned that nothing appeared to be happening notwithstanding that concern was initially expressed in April 1994. Mr Hill asked for advice as to the present status of any remedial work. 67An internal report from the defendant's Director of Engineering Services presented to the Council meeting of the defendant on 18 September 1996 included the following: Gales Holdings Pty Ltd Gales Holdings Pty Ltd are represented by Mr Gary Peacock of Outline Planning Consultants. Mr Peacock has advised that the owners have no urgency to develop this site. This lack of urgency is certainly reflected in the difficulties and time involved in negotiating a purchase. Agreement was reached with Mr Peacock in February 1996 to have independent valuations undertaken, to be exchanged on completion. However, on completion of Council's valuation Mr Peacock advised that his client had instructed him that Council's valuation would be required before any further action would be considered. 68In September 1996 the Bowls Club's solicitor wrote to the defendant requesting information as to whether there was any likelihood of a reasonable engineering resolution of the matters raised by the Bowls Club in relation to the 1200mm pipe. 69On 11 November 1996 the defendant wrote to Mr Hill in the following terms: With reference to your letter of 3 September 1996, I wish to confirm that until filling of the Gales Holdings land proceeds there should be adequate retention area available to satisfy flood drainage in accordance with investigations and calculations by Martin Findlater & Associates. Prior to any development of the Gales Holdings land the trunk drainage system will have to be resolved and the need for a retention basin at this locality is being addressed in this plan. 70On 12 November 1996 the defendant wrote to the Bowls Club's solicitors in terms that included the following: While the Gales Holding land remains at its present level there should be adequate retention area available to satisfy flood damage in accordance with the investigations and calculations by Martin Findlater and Associates. Prior to any development of the Gales Holding land the trunk drainage system will have to be resolved and the retention needs in this locality are being addressed in that scheme. Council is fully aware of the drainage needs in this locality. Final resolution of details cannot be predicted at this time as they are largely related to actions by Gales Holdings. 71The irresistible inference from this correspondence is that the defendant had concluded that until it was filled, the Land would be used as a "retention area" for flood drainage. 72On 24 March 1997 the plaintiff wrote to the defendant enclosing a signed consent form in respect of the permission for the defendant to enter upon the Land for the purpose of constructing Turnock Street. That letter included the following: "Please note that we will need fencing to be erected to ensure that the cattle we run on the property do not escape". Turnock Street completed 73On Tuesday, 9 December 1997 Turnock Street was officially opened. Proposed application to fill the Land 74In March 1998 the plaintiff was considering obtaining development consent for the filling of the Land. A memorandum from Mr Peacock to the plaintiff dated 30 March 1998 included the following: As Mayor Boyd indicated, you will need to obtain in the first instance Development Consent for the filling of your land. With this consent in hand, it will then be possible to make separate applications for various forms of development over your land eg. retail, commercial, townhouses, residential flat buildings etc. Obtaining this consent will then remove any uncertainties over what land can and cannot be developed. 75That advice included reference to steps that needed to be taken prior to the plaintiff being in a position to lodge a development application for filling the Land including the development of a Master Plan for West Kingscliff and a Master Drainage Plan. Mr Peacock sought the plaintiff's approval for the engagement of the services of Bill Knobel, a consulting engineer and principal of Knobel Consulting Pty Ltd (Knobel), to assist with monitoring the work of the development of a Master Drainage Study for West Kingscliff and any follow up engineering work, for example landfill, road design, services provision and drainage. Funding of $21,156 for further studies 76On 12 June 1998 the plaintiff agreed to provide funding of $21,156 to the defendant out of a total budget of $25,100 for the preparation of a drainage/water quality study by WBM Oceanic. The plaintiff drew the defendant's attention to its previous undertakings to notify the plaintiff how the proposed drainage system (including the retention basin) would work and that it had not done so. The plaintiff also drew the defendant's attention to the fact that a final decision on the stormwater scheme for the area was still outstanding. 77On 21 July 1998 Knobel wrote to WBM Oceanics referring to a site meeting in relation to the West Kingscliff master drainage strategy. Knobel confirmed their concerns regarding drainage at the northern end of the Land adjacent to the Nursing Home and the Bowls Club. That letter included the following: It would appear from closer inspection that the local drainage ponds behind the new residential development and has no outlet or Q100 overland flow through the adjacent subdivision. We will be addressing this matter further with Council. We also request that you examine the requirements for drainage under Elrond Drive and Turnock Street. Major construction has recently been undertaken and the Tweed Shire Council would have the construction records and how any drainage structures relate to your previous study. 78The records of WBM Oceanics record a communication with Mr Knobel in which he expressed his concern about the drain behind the Nursing Home and the Bowls Club. Those records also include a record of a phone call to Mr Henley of the defendant which noted that the drain was "a purely hydraulic problem" and that WBM did not need to consider it in their study. WBM records also include a note of a telephone call with Patrick Knight of the defendant on 30 July 1998 that includes the following: He asked about including the problem drain at the back of the Bowls Club land into the study. I paid an extra $4 to $5000 but told him John Henley had advised to leave this drain alone as it has been the subject of previous investigations & further investigations were not required. 79The WBM Oceanics records for 31 July 1998 include notes in relation to a phone call from Mr Knobel as follows: Problem drain actually has a low flow pipe taking water under filled site & directly to main channel. Box culverts in place to provide for flow under road (we didn't see them on initial visit with Bill as they were under weeds). 80On 3 August 1998 a meeting took place attended by Mr Henley of the defendant, Messrs Peacock and Knobel on the plaintiff's behalf, and representatives of WBM Oceanics. Mr Peacock and Mr Knobel suggested that the defendant reduce the size of the proposed drainage through the Land from 50 metres to 20 metres. It was noted that WBM Oceanics would look in more detail at the land near the Bowls Club and that the plaintiff wished to submit a Development Application for landfill immediately after WBM Oceanics study was completed. 81On 10 February 1999 the defendant advised Mr Peacock that the Water Quality Management Study for West Kingscliff was "essentially completed" and provided the basis for more detailed discussions on planning for the Land. Turf farm litigation 82In the late 1990s, probably in 1998/1999, the plaintiff commenced legal proceedings against the defendant to prevent it from proceeding with a turf farm proposal to spread bio solids from a sewerage treatment plant on an area of land adjacent to other land in the area owned by the plaintiff. The plaintiff was successful against the defendant in those proceedings (tr 357). Wallum Froglet identified 83On 7 May 1999 Mr Warren (retained in 1998 by Outline Planning Consultants Pty Ltd on behalf of the plaintiff to undertake a preliminary flora and fauna assessment of the Land including searches for significant fauna habitats) produced a report in relation to his observations and findings from a survey carried out in July 1998. That report included the following: A single Wallum froglet was heard calling from flooded grassland in the south east of the southern property. Warren (1993) considered the Wallum froglet a possible occurrence in the locality. WWC (1996) failed to record this species but considered it a possible occurrence along the table drain over which the Turnock Street bypass crosses. WWC (1996) considered it unlikely that the construction of Turnock Street bypass would have a significant impact on a local population of this species. Based on the availability of habitat and the results of other surveys in the immediate locality, it is considered that this population will be restricted to the small areas of lowlying Paperbark vegetation in Lot 13 and in the intact Paperbark swamps to the south of the southern properties. The drain running through the northern property is subject to saline intrusion and is highly unlikely to provide habitat for the Wallum froglet. The remainder of the area is also generally elevated and does not provide suitable habitat for this species. Woodward-Clyde - May 1999 84On 28 May 1999 Woodward-Clyde produced a report entitled " Statement of Environmental Effect - Flora, Fauna and Fire Hazard Assessment " in relation to the proposed construction of a library near the Land. That report recorded that the Wallum Froglet had been detected in a "brief field survey" and included the following: Habitat Assessment: The wallum froglet was recorded from the site in this region although the majority of its habitat is found off the site in adjoining areas and adjacent land on either side of Turnock Street deviation. Given the disturbed nature of the site, the proposed development is considered unlikely to impact on any native species such that it is placed at the risk of extinction. ... The wallum froglet, north of the site will need to be protected from indirect changes in water quality resulting from development. ... Another species, the wallum froglet ( Crinia tinnula ) was recorded from areas adjacent to the site and occurring just inside the borders of the site near the Turnock Street/Cudgen Road roundabout. This species is listed in Schedule 2 of the Threatened Species Conservation Act 1995 as vulnerable. This species was not previously recorded in surveys of the area but is known to occur in the region and has been recorded from nearby Cudgen wetlands. The NSW National Parks and Wildlife Service Wildlife Atlas records this species from the locality. The habitat for this species is mostly found off site with the exception of the northern most boundary near the roundabout. It appears restricted to the closed fernland communities with occasional paperbark. Habitat for this species as it occurs on and near the site is illustrated in Figure 5. It is not entirely surprising that this species was missed in the previous surveys given that it is known to "appear and disappear" depending on conditions, particularly rainfall and subsequent changes in pH (Greg Czechura, pers comm.). In the supplementary survey this species was detected during the diurnal survey of the site, but was not detected at night. ... The wallum froglet was recorded from the site in this region although the majority of its habitat is found off site in adjoining areas and adjacent land on either side of the Turnock Street deviation. The species appears restricted to the closed fernland habitats within these regions. The habitat on site is considered to be marginal and of low significance to this species given the proportion of more suitable habitat in adjacent areas. It is possible that this species increases and decreases its range according to environmental conditions such as rainfall and disturbance. ... A summary of the potential impacts are provided below: ... Alteration in water quality on low lying flats. This may impact on the wallum froglet habitat north of the site; Changes in hydrology for the remaining habitat areas. This may alter the biodiversity of these areas thus comprising their habitat value. ... The largest detected grouping of the species was found to be between Turnock Street (east) and the new residential area to the north. Additional groupings were detected northwest of the Turnock Street roundabout at the rear of the residential subdivision and south of Turnock Street (east) in the area surrounding the roundabout. 85On 23 August 1999 Mr Knobel notified the plaintiff that commencing on 1 September 1999 a contractor would undertake drainage works through the Land. Mr Knobel noted that unfortunately the water table had been extremely high with much of the Land flooded around the main drain. He also advised that this had been brought about by an unusually high winter rainfall but that water levels were now returning to normality. WBM Oceanics - March 2000 86The minutes of the Council meeting of the defendant held on 19 April 2000 noted that WBM Oceanics had completed the report on drainage management for Kingscliff catchment and that it would guide the drainage strategy in the Kingscliff West area. It was noted that DCP 9 and Contributions Plan 7 would need amendment to reflect the new strategy. Those minutes noted that the WBM Oceanics' report was issued on 24 March 2000 at a total cost of approximately $29,000 with $21,156 being paid by the plaintiff that would be a credit towards future section 94 contributions for drainage works in the Kingscliff catchment. Those minutes also referred to the recommendations for new development in the area as follows: Development and fill is not to cause ponding on adjacent land and overland flow paths must remain open. The drainage of existing properties must not be adversely affected as a consequence of fill operations. A second buffer strip should be incorporated between the existing development along Lorien Way and Blue Jay Circuit, and new development proposed for the adjacent undeveloped land. Again, this buffer strip should incorporate an overland flow corridor and be designed to preserve existing vegetation. DCP 9 Revisited - April 2000 87It was unanimously resolved at that meeting that an amendment occur to DCP 9 incorporating the drainage strategy produced by WBM Oceanics and that an amendment to Section 94 Contributions Plan No. 7 be pursued reflecting the revised drainage strategy. 88During 2000 the plaintiff objected to the proposed expansion of the Kingscliff Shopping Centre and made a written submission to the defendant. On 14 November 2000 the plaintiff wrote to the defendant in terms that included the following: 2 Drainage : There is no discussion of our submission regarding legal drainage discharge rights onto our land, nor the implications and management of Q100 flood flows. Indeed, the report dismisses this issue, noting simply that the Council's Engineering Services Division advises "there are no issues with regard to drainage". With respect, the authority to discharge stormwater onto and across our land is fundamental to the development. At this time, no such authority exists. 89The Minutes of the Council meeting of the defendant of 15 November 2000, at which the proposed extension of the shopping centre was considered, notes that the design did not incorporate any of the recommendations of the Kingscliff Catchment and Drainage Management Plan concerning commercial developments and also that no details were provided to quantify Q100 overland flows and impacts on adjoining land. It included the following: One of the objectors raised concerns regarding site drainage and impacts on land to the south west. Councils Infrastructure Engineer has reviewed the drainage proposed and has advised that the point of discharge proposed by the proponent is into Council's existing pipe in Turnock Street which discharges further south west (along Turnock Street) adjacent to Gales Holding land. In its present form the development proposal is likely to increase peak flows and pollutant concentrations across Gales Holdings land to the south west. The proposal will increase the impervious cover to almost 100% of the site, decrease the stormwater runoff time of concentration and result in substantially increased peak stormwater flow rates. There is no overland flow path available in Turnock Street as there is a sag in the longitudinal gradient of the street adjacent to the subject property. The uncommitted capacity of the existing 750mm pipe is also very limited. To accommodate Q100 flows and minimise nuisance increase to downstream owners it will therefore be necessary to limit discharge from the site (into Council's 750mm pipe) to the pre-development Q 5 level (0.17cu.m/sec). This flow rate can be achieved by on site detention or retention or a combination of both. 90The application was refused at that time. However at a Council meeting of the defendant on 20 December 2000 the application was approved subject to conditions including that the discharge of stormwater onto the Land would be limited to pre-development rates and evenly distributed across the southern boundary by means of a low spillway. The Minutes of that meeting include the following: It should be noted that DCP 9 shows a drainage reserve adjacent to the subject land within the residential zone to the west. This reserve has a width of 50m. This drainage reserve has not been created and whether or not it is developed in the location shown will be a factor in determining the extent the development will impact on development on this land. In respect of the location of this drainage reserve, Council's Infrastructure Engineer has advised that the drainage reserve indicated on the DCP9 plan is still proposed, however its location on the plan is schematic and will not necessarily be in the exact location shown. The plan is indicative only that there will be a drainage reserve and trunk drain in this general location for the purpose of conveying stormwater from the existing urban area south east of Turnock Street in a south westerly direction to the ultimate junction with the major south to north drain through West Kingscliff. Notwithstanding the above, it is considered that the current proposal satisfactorily addresses the potential impact on future development of the land to the west. ... Councils Manager of Planning and Design has advised to overcome the issue regarding legal discharge points raised by one of the objectors that a condition requiring discharge of stormwater into the adjoining property shall be limited to the pre-development as indicated on the drainage plans submitted by the applicant and evenly distributed across the southern boundary by means of a low spillway. 91On 22 February 2001 the defendant noted that there had been a failure of a sewer gravity main adjacent to Quigan Street which had resulted from the main being "undermined by flow from a Council stormwater outlet". Meetings - 2001 92On 6 March 2001 a meeting was held at which both the defendant and representatives of the plaintiff were present. The Minutes of that meeting include the following: (a) Kingscliff drainage plan basis of examining storm drainage issues for Gales Holding properties. (b) There is significant external drainage entering Gales Holdings' properties. This is being examined at the present time by Knobel Consulting and further discussions are to be held with Council once drainage outlets and paths established through the various parcels. (c) It is recognised that there is a need to treat existing stormwater from Kingscliff township before it enters the main drainage system. Land may have to be made available for this to take place. (d) The drainage channel from Turnock Street towards Kingscliff is not fixed in location and opportunity exists to vary the alignment to suit future developments. 93A workshop took place on 5 April 2001 in relation to "West Kingscliff Planning" at which representatives of the plaintiff and the defendant were present. The defendant's record of that meeting dated 12 April 2001 includes the following: The western side of Pearl Street is at a lower level than that which West Kingscliff will be filled and Council has some significant potential stormwater liabilities relating to the planning, design and construction of the Gales Holdings land, with Gales Holdings development being anticipated as a self contained development for drainage and water quality management. Bill Knobel commented upon how ( sic ) and Council had worked very productively together at this point. The fill will be permeable material to assist water quality management. Some significant drainage occurs from the existing Kingscliff township onto the Gales Holdings land and he reinforced how this drainage management and treatment was a significant issue for Council in terms of potential liabilities and expenditure. The Company and Council should work together to work out solutions for the total sub-catchment to agree drainage and water quality outcomes. Re-design of pipes for drainage in Elrond to Turnock will have to be considered and there is an opportunity for water quality treatment area in the vicinity of the junction of Elrond and Turnock. Considerable flexibility is still available in the design of the drainage and water quality systems. There is currently contaminated stormwater disposing onto the Gales Holding property and treatment devices will be required in relation to runoff from the existing Kingscliff township. Darren Gibson commented on how the drainage system can be used as open space and recreation and recreated as landscaped corridors and become as natural as possible. The main drains in the system are likely to be about 1m in depth in "dry times". John Henley acknowledged the residual liability. Northern Drain 94On 24 August 2001 Mr May wrote to the plaintiff in relation to the Land generally. That communication included the following: 14. To the north west near or just below the Bowls Club sporting field, there used to be a large drain running east west to the Chinderah flood drain. It would appear that it was about where Channel Street is. This has been filled. 95This would appear to be the first time that the plaintiff was alerted to the fact that the Northern Drain had been filled. 96In November 2001 Knobel provided a report to the plaintiff which included the following: In addition to managing stormwater generated by the development of its land holdings, Gales Holdings Pty Ltd has also inherited the management of stormwater generated by surrounding urban development, which is discharged directly onto its land. Tweed Shire Council has acknowledged its liabilities in this regard. Detailed drainage analysis of land north of Turnock Street, Kingscliff (Lots 11, 12 and 13 DP 871753) reveals significant problems arising from recent land use planning decisions which have overlooked the formalized conveyance of Q100 stormwater flows to the trunk drainage system serving West Kingscliff. That oversight has significant implications for the management of stormwater on land owned by Gales Holdings Pty Ltd, and consequently, the development potential of that land. 97The reference in this part of the report to the defendant acknowledging its liabilities appears to have arisen from what was discussed at the 5 April 2001 meeting, the summary of which included the reference to Mr Henley acknowledging "residual liability". 98That report referred to Mr Findlater's 1995 report that included the proposal for the construction of a retention basis on the Land, the placement of additional pipes and the inclusion of a lateral drainage system as identified in the WBM Report. Mr Knobel concluded that the extension of Turnock Street to the Elrond Drive roundabout had "effectively dammed all stormwater that is generated within the catchment". Mr Knobel also concluded that there was a compounding of the problem because the invert levels of the culverts under Turnock Street did not allow for the Land to drain freely. Mr Knobel also referred to the WBM Report and reported as follows: Unfortunately with development having been established across the alignment of this proposed lateral drainage channel; the cost of acquiring land, excavating a drainage path and structurally revetting the channel and providing additional infrastructure (ie. bridge or culvert crossings) would be substantial. However, the failure to allow for this drainage path, in accordance with s6 of WBM Oceanic's Conclusions and Recommendations, has severely disadvantaged Gales Holding's development potential and the development potential for other adjoining properties. Planit reports 2001/2002 99Jim Glazebrook & Associates, Town Planners and Development Consultants, on behalf of the plaintiff, retained Planit Consulting Pty Limited (Planit) in 2000 to provide an assessment of the vegetation on the Land in support of its development proposals. In its October 2001 report, Planit reported on that vegetation with passing reference to the fauna in the "Wider Locality". The Wallum Froglet was not the subject of the report other than a description of its physical features and habits and a tabular reference to its scientific name. 100In December 2002 Plaint produced a detailed flora and fauna investigation of the Land. The methods of the survey included diurnal frog call identification conducted across a variety of 50 and 100m grids depending on the complexity and similarity of the available habitat, and nocturnal survey methods such as Elliott traps, Pitfall traps and open wire traps. Trapping efforts were conducted for a total of 650 trap nights with traps set at varying intervals of 10-20m depending on the habitat complexity. Traps remained in place for between 36 and 48 hours and were checked and emptied (when necessary) every eight hours. All trap lines were replicated a minimum of twice over the survey period. 101In the section of the report on amphibians (3.2.1.2) Planit reported that the Paperbark Forest within the southern portions of Lots 26C and 26D were considered the primary habitat for amphibian species on the Land. The largest populations of frog species noted on the Land were recorded in these areas with "suitable breeding habitat for two protected species". Planit reported that following extensive rainfall events in March 2002, Wallum Froglets were recorded calling in a small area adjacent to the Turnock Street roundabout in Lot 11 of the Land. The report included the following: Given the extensive cleared areas located adjacent to this area it is considered that the Wallum Froglet did not relocate into this area but, rather, lay dormant within the soil profile and resurfaced following recharging of the groundwater table. 102Planit concluded that the Wallum Froglets were mainly in the areas of Lots 26C and 26D. It was noted that the defendant had failed to record the Wallum Froglet within this area during its ecological assessments conducted prior to the construction of Turnock Street. The report continued: The failure to record this species and consequent construction of Turnock Street has severed an existing (at the time) movement corridor for the species linking Lots 11-13 ... north of the road to drainage corridors which ultimately link to suitable breeding grounds on the southern portions of Lots 26C & 26D ... It is hypothesised that this action has resulted in the isolation of a small number of individuals which now lay dormant in the soil close to the water table during dry periods as they are unable to retreat to areas of permanent tannic Melaleuca wetland. This retreation has been noted in other areas of the site during dry periods ... Given the above, it is considered that a population of Wallum Froglets does exist on the subject land, predominantly confined to the most suitable habitat area contained within the southern portions of Lots 26C & 26D. ... A small number of isolated individuals which exist adjacent to the Turnock Street roundabout will be impacted upon by the proposed development which proposes the filling of these areas. It is considered that these individuals, which are separated from permanent water, undergo a period of dormancy during drier months and resurface during the winter months or periods of extensive rainfall which raise the groundwater table. Further discussions - 2002 103On 22 January 2002 the plaintiff wrote to the defendant in respect of a draft Tweed Local Environment Plan 2000 Amendment in terms that included the following: Drainage . Council's previous planning decisions resulted in the main open drain servicing Gales land north of Turnock St being filled in, with the Retirement Village now standing on part of it. Gales' recent studies show that filling in this drain, along with other stormwater being directed onto Gales land presents great problems and that the cost to Council of rectifying these past planning decisions could be several million dollars. 104The plaintiff requested discussions with the defendant to seek "solutions". On 7 February 2002 the defendant wrote to the plaintiff advising that the appropriate manner in which to progress matters would be that consultants acting for the plaintiff and the defendant's staff, including any consultants it engaged, should "work together". The defendant advised that it was sure that this would "provide the appropriate outcomes within a reasonable time frame". 105On 18 July 2002 a meeting of representatives of the defendant took place. A memorandum in relation to that meeting included the following: 1. Drainage Issues Around 1995 Council agreed to subdivision works and filling that deleted the eastern branch open channel proposed in the original drainage study report prepared by WBM. A report prepared by Martin Findlater proposed a 1ha detention basin in lieu of the eastern branch. Council resolved 27 September 1995 to amend DCP9 and s94CP7 to incorporate the detention pond. There has been much correspondence on this issue with Gales Holdings, but, there is no agreement with them for these works to be on their land and no agreement on who bears the costs. To solve the drainage issue may cost in excess of $1 Million. Options being Purchase houses to reinstate original eastern branch. Provide a small detention basin (on either their land or Bowling Club Land) and a southern outlet through Gales Holdings land to south of Turnock Street. Provide a large detention basin and utilise the existing underground drainage system as an outlet. Provide no detention basin and use a larger outlet through Gales Holdings land to south of Turnock street. ... 3. Possible Strategies Advise Gales Holdings that it is their problem to deal with upstream drainage as the problem will only occur as a consequence of filling their land north of Turnock Street. They can provide detention storage on their land or purchase land from the Bowling Club. TSC will assist with acquisition of road (but no $) through Bowling Club land. If detention basin needed on Bowling Club land Council would also assist (but no $). Development Application 106On 19 December 2002 the plaintiff lodged a Development Application for a proposed shopping centre on Lots 11 and 12 of the Land. Drainage system inadequate 107In a letter dated 21 January 2003 from the defendant to a resident who had complained about stormwater drainage in Kingscliff Street the following was written: Internal inspections of the piped system indicated that no significant silts or obstructions exist in the system. The problem appears to be that the system has been rendered inadequate to convey runoff generated by development in the area over the years. Works to increase the inlet pit capacity and some additional piping are scheduled for early February 2003. Further discussions - 2003 108In an internal memorandum dated 27 February 2003 Mr Knight of the defendant recommended that the plaintiff's application to develop part of the Land into a shopping centre be refused. In a memorandum of that date Mr Knight wrote as follows: At present an area of approximately 12ha (developed areas of Kingscliff in sections of Marine Pde and Kingscliff St) upstream of Kingscliff Bowling Club land, drain through a stormwater pipe system which runs through the Bowling Club land and thence in a westerly direction via pipes under Blue Jay Way and other streets and reserves to the main Kingscliff Drain. This pipe system is only designed for Q5 capacity, and at present flows in excess of Q5 overflow to unfilled land owned by the Bowling Club and adjacent Gales Holdings land. These lands operate as a detention basin for the in excess of Q5 flows. ... This application (for the shopping centre) would incrementally eliminate detention storage in Gales Holdings land, and the filling proposed by the appended "master plan" would eliminate all detention storage from that land. The combined effect of filling both these parcels of land (without any other compensatory measures) would be to eliminate in excess of Q5 drainage capacity for the upstream catchment and cause flooding of land and property. It can be argued that the land owned by Gales Holdings, being low lying land at the rear of the frontal dunal system is the natural area for runoff to be discharged from the foreshore dune area and acts as a natural detention basin for the foreshore dune area. 109The memorandum then referred to the plaintiff's preferred method of dealing with the external drainage by creating a north/south open drain through Lots 11 and 12 of the Land extending from the Kingscliff Bowling Club land in the north to the Kingscliff drain south of Turnock Street, including a new drainage structure under Turnock Street. The memorandum also referred to the defendant's Engineering Services Division' preferred option being a detention basin of around 0.8ha in the northern section of the Land and also on the Bowling Club land. The memorandum suggested that the reasons that the plaintiff's application should be refused were: 1. In the absence of a master plan for landforming and infrastructure of the whole Gales Holding West Kingscliff site (a) The application has failed to demonstrate that the proposed drainage systems will be compatible with ultimate development of the West Kingscliff area. (b) The application has failed to demonstrate that the proposed landform is compatible with ultimate development of the West Kingscliff area. (c) The application has failed to demonstrate that proposed stormwater quality treatment measures are compatible with ultimate stormwater treatment strategies for the West Kingscliff area. 2. The application has not provided a lawful point of discharge for major and minor stormwater runoff from the proposed development. 3. The application has failed to assess the environmental impacts of filling the site and the impacts on amenity of persons along any potential haul routes. "Permit" withdrawn " 110On 5 March 2003 Mr Glazebrook wrote to the defendant on the plaintiff's behalf in terms that included the following: We are instructed that in the course of at least the last ten (10) years, polluted stormwater from urban catchments upstream of our client's property has been discharged from Council's stormwater drainage system onto our client's holdings at West Kingscliff. In minutes of a workshop meeting held with Council Officers and some Councillors, produced by the Director, Development Services (April, 2001), the then Manager, Water acknowledged Council's " residual liability " in this regard (see extract attached). ... 1. Despite the best efforts of Gales Holdings Pty Ltd, there has been little evidence in Council's process that the long term implications of the unlawful discharge of stormwater onto our client's land, has been objectively and properly considered. 2. Further, there has not been meaningful and proper consideration by Council officers of environmental and strategic planning issues, and 3. In reality there has been a lack of Council initiated discussion and negotiation with our client. This has culminated in the preparation by Council officers of a new version of draft DCP9 - West Kingscliff (version 2) without prior reference or discussion or consultation with Gales Holdings. This is despite the Council's undertaking to work co-operatively with Gales Holdings. In addition, the new draft DCP9 (version 2) has been prepared without awaiting the comprehensive studies being prepared for our client. Council has known about those studies for the whole of their gestation and has encouraged our client to prepare the studies and has indicated to our client that Council would consider the studies in co-operation with our client and in the planning process. However, the draft DCP9 is presented without awaiting these studies and without the benefit of any similarly comprehensive studies. Council has failed to address the stormwater management issues referred to above. We are instructed by our client that it is no longer prepared to permit the unlawful discharge of concentrated stormwater flows from Council's existing drainage structures onto our client's land holdings at West Kingscliff. Council is aware of the importance of drainage and water quality management, which is described in detail in draft DCP9 (version 2). It is inequitable that Council should demand standards that it does not adhere to itself, and has not applied to itself over a period of many years. Our client therefore requires Council to immediately identify all points of illegal discharge of stormwater onto our client's holdings, and take measures to prevent that discharge within ninety (90) days of the date of this notice. 111On 18 March 2003 the defendant wrote to Mr Glazebrook advising that the DCP would address all of the "necessary planning and engineering issues" associated with the area, including strategic drainage issues. The defendant also advised that it was unaware of any unlawful discharge points as referred to in Mr Glazebrook's letter and that all stakeholders including the plaintiff would be fully consulted in completing DCP 9. 112On 4 March 2003 the NPWS wrote to the defendant in relation to the "conservation value" of the Land. That letter specifically eschewed any suggestion that the comments within it were in relation to the plaintiff's DA for the shopping centre. The NPWS advised that there were a number of "regionally vulnerable" vegetation communities on the Land and that it also contained suitable habitat for a number of additional threatened species that had not been recorded to date because of limitations in the survey design and methods. In addition the NPWS advised that the Land was of "critical importance" for the Mitchell's Rainforest Snail, an endangered species under the Threatened Species Conservation Act 1995. It was noted that extensive areas of suitable habitat for the Mitchell's Rainforest Snail occurred within the Land and that an approved Recovery Plan had been prepared for the species which required a detailed consideration of the impact of development proposals on the species. It was also noted that one of the other important populations within the Land was the Wallum Froglet. 113Although the NPWS claimed its comments were not in relation to the plaintiff's DA for the shopping centre the letter included the following: The proposal to develop land on the north and south sides of Turnock Street and the construction of the road linking Turnock Street to Quigan Street is not supported. This proposal would further fragment habitat for Mitchell's Rainforest Snail, increasing the degree of isolation. Isolated habitats will also be subject to altered hydrological regimes and increased edge effects, which over-time, will reduce the quality and viability of habitat. An altered hydrological regime is expected to occur when a large amount of fill is placed in close proximity to snail habitat. The specific habitat requirements of Mitchell's Rainforest Snail make it particularly susceptible to changes in hydrology. The fragmentation and isolation of habitat coupled with potential changes in hydrology and increased extent of edge effect may have a substantial and irreversible impact on snail habitat. 114On 11 April 2003 the proposed action by the plaintiff to develop the Land was designated as a "controlled action" under the Environment Protection and Biodiversity Conservation Act 1999 (Cth). The Commonwealth Department of the Environment and Heritage advised the plaintiff that the Land contained an important population of the "critically endangered" Mitchell's Rainforest Snail and that it considered that site works were likely to directly and indirectly affect important habitat for the snail if adequate controls were not in place. It was also noted that any works associated with the DA for the shopping centre potentially affecting the habitat of the snail could not commence until approval had been given under that Act. Wallum Froglets take hold 115On 12 May 2003 Peter Parker of Environmental Consultants Pty Limited advised the defendant that his review of the reports of Planit, who had been retained by the plaintiff through Mr Glazebrook, led him to the conclusion that Planit had failed to undertake a proper eight part test with respect to the Wallum Froglet. Mr Parker advised the defendant that Planit had incorrectly assumed that the Wallum Froglet on the Land would not be significantly affected despite the construction of a road through its "core habitat", the pumping of 98,000 cubic metres of fill onto the Land and the construction of drainage works to accommodate drainage from a proposed shopping centre onto the remaining Wallum Froglet habitat. Mr Parker advised that there would be significant hydrological changes or changes to nutrient status. He attached a chart to his report comparing the calls of the Wallum Froglets recorded by Planit and the calls he recorded in his survey. That chart recorded that Planit had heard less than five calls of the Wallum Froglet compared with more than 1000 calls heard on 29 April 2003 (during the day) and on 5 May 2003 (during the evening) in his own survey. Blockage of the Elrond Drive culvert 116There is no issue that in mid-2003 there was a blockage of the Elrond Drive culvert. Mr May's unchallenged evidence was that when the culvert was constructed a small area was damaged and a "wooden prop" was placed in the pipe whilst new concrete was put in to replace the broken area. Mr May observed on 9 May 2003: The wooden prop is still in place and had collected masses of accumulated grass around it causing the blockage. This is the only pipe set low enough to act as a drain. Significant ponding 117On 11 August 2003 Planit advised the plaintiff that there had been significant ponding north of Turnock Street and the area was unable to drain because of "previous culvert design". Planit also advised that this ponding was generally greater than 30cm and there were areas with standing water still present after several months. Planit observed that the population of all frog species, including the Wallum Froglet, had increased within the area as a result of "ongoing suitable conditions, likely breeding and potential immigration from other populations on site (as a result of flooding)". Access to the defendant's file 118It was during the latter part of 2003 and early 2004 that the plaintiff's consultants sought access to the defendant's files. The plaintiff was also seeking expert advice in relation to the proposed development of the Land. In May 2004 Ingham Planning Pty Limited advised the plaintiff as follows: Land to the south east around Turnock St experiences ponding and low level flooding generally caused by stormwater flowing in from the developed areas to the east and natural drainage flows being blocked by developments. The altered stormwater flow and ponding has changed the ecological characteristics of the area. This area can be filled if the stormwater is redirected to the west by reintroducing a westward channel, or by providing an open drain south across the property and across Turnock St/Elrond Drive. Nuisance alleged - May 2004 119The plaintiff had received advice from Dr Stephen Webb and on 4 May 2004 the plaintiff's then solicitors wrote to the defendant in the following terms: In the opinion of Dr Webb, the Turnock Street extension effectively acts as a dam for even small storm events. Clearly adequate under-road and lateral drainage is required to ensure that unnatural ponding does not continue to occur to the north of Turnock Street. The above set of circumstances constitutes an unreasonable interference with the reasonable use and enjoyment of our client's land and as such amounts to a legal nuisance. Our client now asks that Council urgently review the problems created by Council's construction of Turnock Street through our client's above land with a view to Council advising that it will, as a matter of urgency, make alterations to the drainage to stop the unnatural ponding occurring. This should be carried out in consultation with our client's hydrologist, Dr Steve Webb. 120On 12 May 2004 Mr Knobel gave permission to the defendant to enter the plaintiff's land to re-establish the outlet to the stormwater drainage discharging from Cudgen Heights. Mr Knobel advised that the works would entail excavating the outlet through the existing grass and feathering the outlet works into the existing drainage paths across the Land. Mr Knobel requested the defendant to provide an inventory of all existing stormwater pipes discharging onto the Land. 121On 14 May 2004 the plaintiff's solicitors wrote to the defendant reporting on a number of matters. The first was a council drain at the eastern end of Turnock Street discharging water onto the Land causing "increasing wetness". The letter continued: The discharge of the water substantially interferes with the reasonable use and enjoyment of our client's land and our client holds Council responsible for all loss and damage suffered as a result of the discharge of the water. 122The plaintiff's solicitors invited the defendant to inspect the Land to make an assessment of this matter. That letter also included the following: 3. Our client has in recent times become aware of the filling of lateral drain B at the northern end of the Noble Park Estate and being the drain shown as lateral drain B in the Kingscliff Drainage Strategy Plan, WBM 1994. The filling in of the drain which was allowed by Council means that there are no remaining direct drainage paths from our client's land to the Tweed River. Our client has recently obtained from Council's files a copy of a letter written by Ian Hill & Associates on behalf of Kingscliff Bowls Club and the Blue Nurse Association being a letter dated 17 June 1994. ... Council's method of resolving the drainage problem was to deliberately provide for the stormwater from the Kingscliff urban area to flow onto our client's land in the short term and then propose a detention basin to solve the problem in the long term: letter of 23 March 1995 from Council to our client proposing amendment to DCP 9 to include a 1 hectare area for a stormwater detention basin. Council failed to advise our client that the reason for requiring the detention basin was the filling in, with the approval of the Council, of lateral Drain B. In other words Council did not require the developer of the Noble Park Estate to rectify the drainage problem which their actions, taken with the Council's approval had caused, but rather arranged with those developers to have the drainage problem dealt with by (intentionally) ensuring the water flowed onto our client's land and be retained there and flow through our client's land. This deliberate concentration of water on our client's land, however, was plainly unlawful. Our client has not until recently been aware of the above matters or of the consequences to our client's land. Please immediately advise Council's proposal to rectify the position described above. 123The plaintiff's solicitors also repeated Mr Knobel's request for an inventory of all stormwater drainage paths onto the Land and for such inventory to be provided within 10 days. 124On 18 May 2004 a meeting took place between representatives of the plaintiff (Mr Gibson from Jim Glazebrook & Associates and Mr Knobel) and the defendant (Mr Hodges, Director Planning & Environment and Mr Knight, Infrastructure Engineer). Discussion in relation to "drainage issues" included that the defendant would investigate the establishment of a table drain north of Turnock Street to convey water westward to the existing "low flow" pipes under Elrond Drive to ease the ponding problem on the Land north of Turnock Street. The plaintiff's representatives advised that the plaintiff's preference was for the re-establishment of an open drain similar to the Northern Drain. In the defendant's note of the meeting it is recorded that the defendant did not consider this to be "a realistic option for cost and political reasons". 125On 6 July 2004 the defendant wrote to the plaintiff's solicitors referring to their correspondence of 4 and 14 May 2004. That letter included the following: The development of your client's land, and other adjacent land in Kingscliff, will require significant amounts of filling to raise these lands above flood level. This filling and previous filling/drainage work irreversibly change the natural landform and as a consequence change the natural drainage patterns of the area. Council acknowledges that the West Kingscliff area requires a comprehensive drainage strategy to satisfy landowner's and Council's needs. In this regard, Council in partnership with your client commissioned a report by WBM in 1998 to investigate drainage issues in West Kingscliff. Your client's consultant Garry Peacock was a key contributor in this investigation and the final report. Council officers are now meeting with your client's representatives (Darren Gibson of Jim Glazebrook & Associates and Bill Knobel of Knobel Consulting) on a regular basis to further develop and progress structure planning of your client's land. Drainage strategies for lots 11 and 12 referred to in your letters have been analysed in detail at these meetings and there is significant agreement on key drainage issues. It is expected that the final outcome of these meetings will be a drainage strategy that is equitable and acceptable to both parties. 126The Minutes of a Council meeting on 4 August 2004 note that a comprehensive plan for the Land was considered to be essential and the sooner this was achieved the better. It was proposed that a small technical group under the chairmanship of the Manager Strategic Planning of the defendant be established to complete a comprehensive draft Structure Plan for the Land for reporting to the defendant by the end of November 2004. It was also noted that DCP 9 required a major review particularly in respect of the Land. Freedom of information litigation 127After the plaintiff obtained the defendant's files referred to in the correspondence extracted above, it sought access to a report in the defendant's possession produced by Core Economics. The defendant refused the plaintiff access to that report and the plaintiff commenced proceedings in the Administrative Decisions Tribunal. The plaintiff was successful in this litigation and access was allowed to that document in mid 2005 (tr 367). Proposed DA to fill the Land 128On 3 November 2004 the plaintiff wrote to the defendant in terms that included the following: Gales has been trying to develop its land and build a supermarket centre at West Kingscliff for many years. This required fill and the most critical component of this was drainage in the area that Turnock St now crosses. A letter from Mr Rayner Director Engineering Services dated 22/6/1995 refers to this. Information recently available to Gales indicates that the cause of the drainage problems was alterations in the natural drainage flow. These issues were raised at a Development Assessment Panel (DAP) on 5 February 1998 (Council's minutes attached). These minutes were not entirely accurate and there was subsequent correspondence regarding this. The reason that Gales has not built a shopping centre as mentioned in points 6 and 7 of the DAP minutes is that the land could not be filled till the drainage problems were resolved. ... Gales has paid for drainage studies done under Council control to enable filling of the area - specifically Ray Sargent and WBM, but neither of these mentioned the cause of the drainage problems (filling in of the natural drainage path and the drainage canal) or enabled filling to proceed, despite these being the specific reasons for Gales paying for the studies. Council was fully aware of the cause of the drainage problems and Gales was totally unaware, and was kept uninformed despite paying for those studies. Over the years Gales has tried to work with Council to resolve the issues and has had extensive studies done at great cost which have defined to a certain degree the cause of the problems and suggested some alternative solutions. Gales intends to submit a DA for filling the area north of Turnock St around the first week of December 2004 - in 4 to 5 weeks. A critical component of this is how the water flow external and upstream from Gales property, that previously flowed to the north and west away from Gales property, might be handled, possibly by flowing southwards across Gales property. Gales seeks most urgently a meeting with Council to determine a final outcome of the drainage strategy. 129On 9 November 2004 the Department of Environment and Conservation (NSW) wrote to the defendant advising that the plaintiff's application to develop its Land by the construction of a shopping centre and associated car parking facilities was not supported "due to its potential impacts on threatened species and their habitats". The Department noted that it was the Commonwealth Department of Environment and Heritage that determined whether a development is a "controlled action" under the Environment Protection and Biodiversity Conservation Act 1999 (Cth) and noted that the development proposal was in the immediate vicinity of a significant population of the Mitchell's Rainforest Snail. The Department recommended that the defendant forward the application to the Commonwealth Department for consideration. 130On 11 November 2004 Jim Glazebrook & Associates wrote to the defendant on the plaintiff's behalf referring to the plaintiff's request in its letter of 3 November 2004 for an urgent meeting with the defendant. That communication included the following: As you would be aware, there is a need for Council to convey stormwater away from affected properties upstream of Gales Holdings land in major storm events. Council has indicated a preferred option involving some form of conveyance through Gales Holdings land. In this regard, Gales believes that its interests have been adversely affected by prior events which were not of its doing and were outside its control. Gales Holdings has incurred significant losses and costs caused by the drainage problems, including funding Council studies (WBM, Ray Sargeant ( sic )) and its own independent investigations in an effort to identify the problems and possible solutions. Through its own investigations, Gales believes that it has identified the causes of the drainage problems. To this end, it has also investigated possible technical solutions to the conveyance of upstream flows. Further discussions on technical matters are to take place with Council's Patrick Knight on 16 November 2004. In an effort to resolve this matter in a mutually acceptable way, Gales would be prepared to consider certain options involving its land, subject to an appropriate consideration (financial or otherwise). Table drain constructed 131In 2004 the plaintiff, with advice from Dr Webb, constructed a table drain north of and parallel with Turnock Street. The initial table drain was built according to usual drainage practice however there were problems with the invert. Dr Webb observed puddles in the drain and concluded that the drain was not operating properly. The problem was subsequently remedied with a laser leveller and the table drain was graded appropriately all the way to Elrond Drive culvert. 132By letter dated 24 November 2004 the defendant advised the plaintiff that it had to address a number of issues in relation to the DA being non-compliant with the defendant's "adopted drainage strategy". The "adopted drainage strategy" was defined in the letter as "see DCP9, CP7, WBM Report 'Kingscliff Catchment & Drainage Management Plan'". This "strategy" included the "dedication of a 50m wide drainage easement for drainage and associated linear parkway use". The plaintiff's DA included the proposed reconstruction of some drains which the defendant advised included non-compliant "cross sections". The defendant advised the plaintiff that any departures from the drainage strategy must be justified and, in particular, it must be demonstrated that the "proposed departures will be consistent with provision of adequate drainage for the entire catchment in its ultimate development form". The defendant also advised the plaintiff that there would need to be treatment ponds of an area equal to 5% of the contributing catchment located adjacent to or along and immediately north of the proposed drain. The defendant requested the plaintiff to address the "issues" preferably within 28 days, after which a further assessment of its DA would be considered. 133On 21 December 2004 the defendant served on the plaintiff an "Order under section 124 Local Government Act 1993" requiring it to remove excess vegetation (specifically long grass) from the Land along the boundary of Cudgen Road and the fence line of Boomerang Street to ensure that the Land is "placed or kept in a safe or healthy condition". LEP litigation 134The plaintiff and the defendant were also in negotiations in relation to a land swap of areas other than the Land. By amendment to the Tweed Local Environmental Plan that came into force on 6 August 2004 the defendant rezoned some aspects of that land. The plaintiff commenced legal proceedings in which the defendant was named as the second defendant and at first instance failed in establishing that the amendment was invalid: Gales Holdings Pty Ltd v Minister for Infrastructure and Planning and Anor [2005] NSWLEC 617. DA to fill the Land - 2005 135In late 2004 or early January 2005 the plaintiff lodged a DA to fill the land north of Turnock Street and to construct a shopping centre south of Turnock Street. On 31 January 2005 the defendant wrote to Mr Glazebrook in response to that DA in terms that included the following: After discussing the matter with staff, and in view of the open manner that Council has and is discussing the future structure of Kingscliff with your representatives, it is considered that the lodgement of the Development Application for filling on the north side of Turnock Street is pre-emptive given all the studies and planning required for this location. This Development Application substantially commences the process of subdivision and development of the area north of Turnock Street including the effects on fauna and flora in the immediate area and in Kingscliff as a whole. The subdivision of this area would be a SEPP 71 matter, and in view of this and the need for providing a strategic structure for the development of Kingscliff, it has been decided to report to Council on the process needed to review and replace the existing Development Control Plans (DCP) for Kingscliff with options (including Gales Holdings option) for the development of the area, especially greenfields sites adjacent to the existing town centre. 136On 7 February 2005 the Commonwealth Department of the Environment and Heritage wrote to the plaintiff advising that its DA had been referred to it on 5 January 2005 for decision as to whether or not approval was needed under Chapter 4 of the Environment Protection and Biodiversity Conservation Act 1999 (Cth). The letter advised that the Department had decided the proposed development was a "controlled action" and therefore the development could not continue without approval under Part 9 of the Act. The Department also advised the plaintiff that it was responsible for carrying out certain steps as part of a requisite environmental impact assessment, the first of which was to provide preliminary information as the basis for determining the level of assessment. 137On 15 March 2005 Jim Glazebrook & Associates wrote to the defendant referring to recent discussions regarding the status of the plaintiff's DA and a proposal for a meeting between the ecologists acting for both the plaintiff and the defendant. The issue for discussion was whether or not a Species Impact Statement was required, a matter in respect of which the parties were in disagreement. 138On 17 March 2005 the plaintiff wrote to the defendant referring to Mr Glazebrook's letter of 15 March 2005 and advising that the plaintiff had to determine whether to commence an action for the defendant's deemed refusal of the DA to fill the Land and to construct the shopping centre. That letter included the following: In reviewing the Agenda of the Meeting of 7/10/2004 it seems most issues have not been much advanced, despite being critical to the DAs. Indeed, Council's minutes of 2/3/2005 record that Gales actions are pre-emptive. This despite Gales having first discussed a supermarket on the same site with Mr Jardine on 28/7/1997 and Mr Broyd on 13/10/1997, and with Council's Development Assessment Panel on 5/2/1998, where Mayor Boyd said the area should be filled as the first step in development. Gales has been continuously trying to fill the area ever since, at all times with full and open communication to Council. Council concealed from Gales that the reason that drainage was a problem was that Council had allowed the natural drainage flow path to be blocked in 1992. Proceedings in relation to deemed refusal of DA 139The plaintiff appealed to the Land and Environment Court against the deemed refusal of the DA to fill the Land and the deemed refusal for the development of the Land south of Turnock Street into a shopping centre. The defendant contended that a Species Impact Statement was necessary before the DAs could be determined and was successful in that contention: Gales Holdings Pty Limited v Tweed Shire Council [2006] NSWLEC 85; Gales Holdings Pty Limited v Tweed Shire Council [2006] NSWLEC 212. 140They were four experts, two retained by the plaintiff and two retained by the defendant, who disagreed as to whether the Turnock Street and Elrond Drive embankment/road was a barrier to movement of the Wallum Froglets. In those circumstances a Court Appointed Expert was instructed to ascertain whether the "Wallum Froglet or its tadpoles are able to use or are likely to use in the context of genetic interchange any of the drains under any of the roads on the land or cross any of the roads surrounding land for the purposes of movement between those portions of land on the northern side of Turnock Street, the southern side of Turnock Street and the western side of Elrond Drive": Gales Holdings Pty Limited v Tweed Shire Council [2006] NSWLEC 212 at [18]. The Court Appointed Expert concluded that the Wallum Froglets could traverse pipes under Turnock Street and Elrond Drive but that there was little likelihood of them doing so. The expert also concluded that the Wallum Froglets could cross over both Turnock Street and Elrond Drive with a reasonable chance of success between the hours of midnight and 6 am. Present proceedings commenced 141On 26 May 2005 the plaintiff's solicitors, Allens Arthur Robinson (AAR) (the plaintiff had also retained a firm, Woolf Associates, to which reference is made in some of the correspondence) wrote to the defendant advising that they had been instructed to commence proceedings against the defendant in respect of nuisance and negligence in respect of "the drainage problems" on the Land and "consequent changes in the ecology and difficulties in developing the land as result of acts (and lack of action)" by the defendant. AAR referred to the filling of the Northern Drain, the manner in which Turnock Street was constructed and the defendant's conduct in relation to the surrounding developments. After further communication these proceedings were commenced. Public allegations 142In April 2006 the plaintiff published pamphlets alleging that the defendant was deceiving the public. Those pamphlets included allegations that the defendant's officers had manipulated reports, provided false information or withheld vital critical information that would completely change the results and recommendations of certain reports on major projects in the area. There were also allegations that Mr Jardine had suppressed or hidden a report obtained in the Freedom of Information proceedings. 143On 24 May 2006 the plaintiff wrote to Mr Mike Rayner, who had recently been appointed as the General Manager of the defendant, referring to the "relevant history going back many years" and in terms that included the following: Gales, as always, would welcome the opportunity to meet in any forum with a view to genuine discussions with a view to resolving the many complex issues to allow proper development for the ultimate benefit of the community. Gales believes that such meetings, if you or the Administrators should agree, should take place without delay as the numerous Court cases that Gales has been forced to undertake will continue to consume resources in time, money and effort that would be better spent on productive endeavours. 144On 22 June 2006 Mr Rayner responded to the plaintiff's letter of 24 May 2006 in the following terms: Could I say in the first instance, that Council is very keen to find a solution in partnership with you to the many complex issues that have evolved between your company and Council. Council Administrators had appointed Mr John Mant, at no small cost to the Council, to attempt in the past what you are proposing to be done now. Council would need to be assured, before it embarks on any further mediation, that the company and particularly its members are genuinely seeking a fair outcome and resolution of all outstanding matters. Prior to entering into further discussions with you in regard to the mediation process to be adopted your company needs to demonstrate good faith by, in the very least: 1. Publicly apologising to Mr Douglas Jardine for the false, outrageous and hurtful comments made by Gales Holdings Pty Ltd in recent times. 2. Making arrangements to pay the Council the substantial outstanding legal costs that your company already owes the Council. Litigation continues 145The litigious relationship between the plaintiff and the defendant continued. The plaintiff appealed from the judgment in which it failed to establish that the amendment to the Tweed Local Environmental Plan was invalid. The plaintiff was successful in the Court of Appeal: Gales Holdings Pty Limited v Minister for Infrastructure and Planning and Anor [2006] NSWCA 388. Tobias JA, Beazley JA agreeing and Basten JA dissenting, held that the amendment was invalid as the defendant had, inter alia , failed to take into account a report prepared by Core Economics who had been engaged to advise the defendant on a retail development strategy. More complications 146The relationship became more complicated in late 2007 when the defendant notified the plaintiff that it had received complaints concerning unauthorised drainage works on the Land. The defendant directed the plaintiff to cease any further drainage works failing which immediate legal action would be commenced. 147On 30 June 2008 AAR wrote to the defendant's solicitors referring to the previous correspondence in terms that included the following: We are instructed that since Woolf Associates' letter of 22 October 2007, the condition of the Quigan Street Outlets have deteriorated further. In particular we understand that the concrete apron has become significantly undermined and that a large block of concrete previously forming part of the apron has broken off and is now lying several metres below the road in the channel on our client's land created by water flowing out of the Quigan Street Outlets. We are instructed that the undermining of the concrete apron and of the land on the road reserve around the Quigan Street Outlets is now so significant that when a member of the public was walking on the road reserve next to the gutter diversion, the ground gave way under one of his feet and he found that his leg was in a hole. We are also instructed that cracks can be observed in and near the road surface beside the Quigan Street Outlets. Our client is concerned that this presents a serious potential danger to members of the public including children travelling to and from a nearby school. Our client is also concerned about the scouring and gouging of its land near the Quigan Street Outlets, and the resulting deposition of this material further downstream blocking the open channel. The scouring and subsequent deposition is a result of stormwater flowing from Quigan Street Outlets without any energy dissipation system in place to slow down the flow of stormwater on to our client's land. ... Our client is concerned that the volume and quality of untreated stormwater flowing out of the Quigan Street Outlets can cause damage to the Mitchell's Rainforest Snail habitat. We are also instructed that the undermining of the concrete apron and the road reserve above the Quigan Street Outlets has exposed a length of the sewer line and that a blue repair section can be seen on the sewer line where our client understands it was repaired by Council several years ago. Our client is concerned that the exposed sewer line could be vulnerable to rupturing as it did previously, which could cause raw sewerage to flow on to the Mitchell's Rainforest Snail habitat. 148AAR requested that the defendant take a number of steps including the installation of energy dissipation works below the Quigan Street Outlets. Development Consent 149On 14 July 2008 the Land and Environment Court granted development consent for the plaintiff's development on certain conditions: Gales Holdings Pty Limited v Tweed Shire Council [2008] NSWLEC 209. On 28 August 2008 the Land and Environment Court Orders were entered upholding the plaintiff's appeal and granting development consent to fill the Land subject to conditions including that the consent would not operate until the plaintiff satisfies the defendant by producing satisfactory evidence of various matters set out in Schedule A of the conditions. Those matters included the production of a Wallum Froglet management plan and monitoring and reporting in relation to matters including climatic conditions, water quality and hydrology. They also included a requirement that the results of the monitoring be given to the defendant at the end of each season together with a final report after 12 months with conclusions regarding Wallum Froglet numbers, population fluctuations, number of breeding events and observations of water quality and the length of the time there is standing water. The conditions also required a stormwater network with two separate water quality treatment criteria, one being for the Wallum Froglet habitat and the other for all other stormwater. There are also conditions in relation to the quality of the fill to be used and a condition that if the fill had a shell grit content in excess of 1%, an impermeable barrier is to be placed within the fill batter to the Wallum Froglet precinct. Blue Jay Circuit Scheme 150The defendant has proposed stormwater augmentation works in relation to what has been described as the "Blue Jay Circuit Drainage Scheme" (Blue Jay Circuit Scheme). Blue Jay Circuit is part of the road system adjacent to the Land and within the NPE, intersecting with Lorien Way. The Review of Environment Factors in respect of the Blue Jay Circuit works (Ex GG) recognises that "surplus flows greater than a Q5 storm event" flow down stream "via default" onto the Land "as the inlet capacity is exceeded". It includes an "upgrade" of the 1200mm pipe and there is no issue that the implementation of this augmentation will adequately address the problems the plaintiff is experiencing with the increase in stormwater runoff onto the Land. There is no issue that the defendant has commenced these works, however they are not to be completed until a contribution is received from the developer of the Nursing Home. It is not clear when such a contribution will be made. The proceedings 151When the plaintiff commenced these proceedings in 2005 claims were made against the defendant in negligence and nuisance. The plaintiff sought an injunction to restrain the defendant from causing or permitting stormwater runoff to discharge onto the Land so as to cause a nuisance, an order that the defendant carry out works to abate the nuisance and equitable damages. The pleadings have been amended over the years and on the seventh day of a nineteen-day trial the plaintiff abandoned its claim in negligence. Its claim against the defendant for an injunction and damages is now based only in nuisance. 152The proceedings were heard on 15, 17 and 21 February, 2, 3, 4, 7 to 11, 14, 15 and 18 March and 4 to 8 April 2011. Mr TF Robertson SC, leading Mr M Green, of counsel, appeared for the plaintiff. Mr SR Donaldson SC leading Mr S Glascott, of counsel, and Mr N Broadbent, of counsel, appeared for the defendant. 153At the commencement of the trial the plaintiff relied upon a document of 18 pages entitled "Outline of Opening Submissions" dated 14 February 2011 and the defendant relied on a document 10 pages entitled "Outline of Submissions" dated 11 February 2011. In an attempt to identify the real issues the parties were ordered to prepare an Agreed Statement of Facts. A document of 42 pages entitled Agreed Facts (Ex PD 12) was handed up in Court on 3 March 2011 but it was not agreed (tr 225). During final submissions on 6 April 2011 the plaintiff filed a document of 18 pages entitled "Outline of Hydrology Evidence and Contentions". It also filed a document of 6 pages entitled "Plaintiff's Outline of Claim" together with a document of 2 pages entitled "Proposed Orders" with an attached plan and drawings. 154During final submissions on 7 April 2011 the defendant filed and relied upon a document of 52 pages entitled "Written Submissions". When the matter concluded on 8 April 2011 the parties sought and were granted leave to file further written submissions. On 12 April 2011 the plaintiff filed a document of 51 pages entitled "Plaintiff's Schedule of Documentary Evidence based on Agreed Facts and Documents referred to in Court" said to be "substantially based on the Agreed Facts Document" (Ex PD 12). On 18 April 2011 the defendant filed a document of 85 pages entitled "Defendant's Response to Plaintiff's Schedule of Documentary Evidence", a document of 3 pages entitled "Defendant's Supplementary Submission" and a document of 23 pages entitled "Defendant's Supplementary Chronology". On 10 May 2011 the plaintiff filed a document of 74 pages entitled "Submissions in Reply" and a document of 9 pages entitled "Appendix: Reply to Defendant's response to Plaintiff's schedule of documentary evidence and to Defendant's supplementary chronology". Judgment was reserved on 10 May 2011. Issues on plaintiff's claims 155The plaintiff makes a number of claims in relation to the defendant's conduct since 1994 as the cause of the alleged nuisance. 156The first claim is that the defendant permitted the filling of the Northern Drain by 1995 and failed to create an adequate alternative drainage route. There is really no issue that the Northern Drain was filled by 1995. The defendant conceded that the developer of NPE failed to comply with condition 43 of the Development Consent (the construction of a drainage overflow path along the northern boundary of NPE). Condition 43 was imposed in circumstances where the defendant knew that the Northern Drain would be filled during the development of NPE and no doubt saw it as a necessary step to facilitate proper drainage of NPE and the surrounding properties. NPE constructed the 1200mm pipe, however the legal title to the drainage network vested in the defendant. The real issue in relation to this claim is whether in all the circumstances this was an adequate, alternative drainage route to the Northern Drain. 157The second claim is that the defendant constructed Elrond Drive with inadequate culverts and without table drains. There is no issue that there was only one culvert under Elrond Drive and there were no table drains constructed by the defendant. The real issue in respect of this claim is whether in all the circumstances that single culvert was adequate for the proper drainage of the Land. 158The third claim is that the defendant constructed Turnock Street in 1997 with inadequate culverts and table drains. There is no issue that there were no culverts at ground level and there were no table drains constructed by the defendant. There were three culverts about halfway up the embankment of Turnock Street that would only be of any use in a major flood and/or when the Land was filled. It appears that the defendant constructed the culverts at that level in anticipation of the Land being filled. The issue in respect of this claim is whether in all the circumstances this construction was inadequate for the proper drainage of the Land and/or was an impediment to the proper drainage of the Land. 159The fourth claim made by the plaintiff is that the defendant failed to provide adequate fauna access under Turnock Street and Elrond Drive. The only way that any fauna can travel under Turnock Street and Elrond Drive is through the culvert under Elrond Drive and the Turnock Street culverts. Mr Robertson indicated that after the appeal to the Land and Environment Court in relation to the deemed refusal of the DA to fill the Land (referred to earlier) the plaintiff "subsequently found through further expert analysis that the frogs did cross the road and were seen crossing the road" (tr 74). In those circumstances this does not appear to be an issue in the case. 160The fifth claim the plaintiff makes is that the defendant permitted blocking of drainage of stormwater runoff from the Land and from surrounding land to the Natural Watercourse (by reason of approval of development of the Nursing Home) and has failed to construct an adequate alternative drainage route. There is no doubt that the defendant approved the development of the Nursing Home and that in allowing development of the Nursing Home and other developments to the north of the Land the Natural Watercourse to the north of the Land has been blocked. This fact needs to be taken into account when considering the other issues in relation to the adequacy of the drainage of the Land. 161The sixth claim the plaintiff makes against the defendant is that it permitted the extension of Lorien Way without provision for the Northern Drain to flow under it and has failed to construct an adequate alternative drainage route. There is no issue that the defendant permitted the extension of Lorien Way without provision for the Northern Drain to flow under it. The defendant conceded that the extension of Lorien Way in 1994 blocked the Northern Drain. This fact needs to be taken into account when considering the other issues in relation to the adequacy of the drainage of the Land. That consideration also needs to take into account the circumstance that the defendant has resolved to construct the Blue Jay Circuit Scheme. 162The seventh claim the plaintiff makes against the defendant is that it permitted filling of the Eastern Drain between 1992 and 1995. There is no real dispute that the Eastern Drain was filled between 1992 and 1995 when the plaintiff consented to the establishment of batters on the eastern perimeter of the NPE and the western boundary of the Land. The fact that the Eastern Drain is no longer available for the drainage of stormwater off the Land is a circumstance to be taken into account in considering the other issues in relation to the adequacy of the drainage of the Land. 163The eighth, ninth and tenth claims the plaintiff makes against the defendant relate to the Quigan Street outlets. They are respectively that: the defendant constructed, or permitted construction, of the stormwater outlets and gutter diversion at the corner of Quigan Street and Boomerang Street discharging stormwater runoff onto Lot 13; constructed or permitted construction of a stormwater outlet near the corner of Quigan Street, Herford Street and Cudgen Road and to the west of that intersection discharging stormwater runoff onto Quigan Street road reserve and then onto Lot 13; and constructed a stormwater outlet on the southern edge of Turnock Street near the north eastern corner of Lot 13 discharging stormwater onto Lot 13. There is no dispute that stormwater is being discharged onto the Land from the Quigan Street outlets and onto Lot 13. 164The fact that there is stormwater discharge onto the north eastern corner of Lot 13 north of Turnock Street is to be taken into account when considering the issue of the adequacy of the drainage of the Land north of Turnock Street in all the circumstances, including the adequacy of the 1200mm pipe, the closure of the Northern and Eastern Drains, the construction of the single culvert under Elrond Drive, the lack of culverts at ground level under Turnock Street and the closure of the Natural Watercourse to the north of the Land (the other drainage issues). 165The eleventh and twelfth claims against the defendant relate to other outlets constructed by the defendant from which stormwater flows onto the Land. Those claims are respectively that the defendant: constructed or permitted construction of a stormwater outlet near the north eastern corner of Lot 6 carrying stormwater from Pearl Street which directly or indirectly discharged onto Lots 11-13; and constructed or permitted construction of two stormwater outlets on the northern corner of the Land in Lot 11 discharging stormwater onto that Lot. These facts are not in serious dispute. They are to be considered in relation to the other drainage issues. 166The thirteenth claim the plaintiff makes against the defendant is that it allowed development within the catchment whereby the volume, frequency, velocity and peak flows of stormwater redirected and concentrated through the stormwater outlets is unreasonably increased. It is clear that the volume of the stormwater has increased. There is an issue as to whether the frequency, velocity and peak flows have increased. There is also an issue as to whether, if the frequency, velocity and peak flows have increased, such increase has been unreasonable. 167The fourteenth claim the plaintiff makes against the defendant is that it permitted and continued to permit urban stormwater runoff to flow onto the Land via the stormwater outlets without appropriate treatment for water quality (eg. gross pollutant traps and sediment traps as referred to in DCP 9). There is no dispute that there are no gross pollutant traps or sediment traps. The issue is whether the absence of those traps is causative of a nuisance. 168The fifteenth claim the plaintiff makes against the defendant is that it failed to maintain on a regular and timely basis, or at all, the drains which it owns or is responsible for and which would, if properly maintained, convey stormwater away from the Land. There is no dispute that the defendant did not have a system of regular checks on its drains. 169The plaintiff claims that the consequences of the defendant's conduct are that: (1) stormwater runoff pools and remains in and on the Land more frequently, for longer periods and in greater quantities than in its natural state and/or its undeveloped state; (2) stormwater runoff coming upon the Land is diverted and altered from its usual and regular course; (3) the quality of the stormwater runoff coming onto the Land is decreased; (4) stormwater runoff is prevented and obstructed from passing through and flowing from the Land into the drains and the Natural Watercourse; (5) the stormwater runoff coming onto the Land is redirected and concentrated and is in greater volumes and with greater velocity and frequency and higher peak flows; (6) the Land is flooded more frequently, for longer periods and in greater quantities than in its natural or undeveloped state; and (7) there have been ecological changes on the Land (first observed by the plaintiff in about 2001) including the creation of habitats suitable for Wallum Froglets. 170Although not expressly admitted there is really no serious dispute in relation to claims (1), (2), (4), part of (5), and (6). There is no issue that the Land has "wetted up" by reason of some of the defendant's conduct. The real issue for determination, along with a number of other sub-issues, is whether that wetting up amounts to an actionable nuisance against the defendant. Expert Opinion 171Many of the issues for determination have required the assistance of expert opinion. The questions of the adequacy of the 1200mm pipe, the culverts in Turnock Street and the Elrond Drive culvert to drain the Land need to be addressed in the context of the physical circumstances of the Land, including the soil content and vegetation. It has also been necessary to review the likelihood of ponding of the water/stormwater in particular periods creating ephemeral ponding as a breeding ground for Wallum Froglets. 172The Court was assisted by the expert opinion of witnesses with expertise in various fields including hydrology [Dr Stephen Webb (hydrologist/engineer) and Mr Drew Bewsher (hydrologist)], vegetation [Dr Andrew Benwell (botanist/plant ecologist), Dr Anne Clements (plant ecologist), Mr Andrew Murray (botanist/vegetation ecologist) and Dr Andrew Smith (applied ecologist/eco-system management)], soil [Dr Pam Hazelton (soil scientist)] and ecology/fauna [Dr Andrew Smith, Dr Michael Mahoney (ecologist/conservation biologist) and Mr Peter Parker (ecologist/environmental consultant)]. The experts gave evidence in concurrent session in their relevant specialties with Dr Smith giving evidence in two concurrent sessions. An agenda for discussion with each group of experts was prepared to assist in the determination of the issues in dispute. The parties have addressed their cases and submissions in part by reference to these categories of expertise. Hydrology Issues 173The first area of expert evidence that requires assessment is that of the hydrology experts, Dr Stephen Webb and Mr Drew Bewsher. Their evidence is relevant to the adequacy of the drainage of the Land, in particular the issues in relation to the adequacy of the 1200mm pipe, the culverts under Turnock Street and the Elrond Drive culvert. They also commented on other issues such as the level of groundwater and the likelihood of ponding on the Land in particular periods. Opinions of the experts in other specialities will also impact upon the hydrology issues. For instance, the nature of the vegetation on the Land at particular times and the likelihood or otherwise that the increase in the stormwater in the circumstances of alleged inadequate drainage changed the nature of the vegetation such as to create a Wallum Froglet habitat. 174Dr Webb's reports are dated 25 August 2010 and 1 March 2011. Mr Bewsher's reports are dated 2 December 2010 and 21 February 2011. There are Joint Hydrology Reports of 22 January 2011 and 3 March 2011. The hydrology experts engaged in a joint conference and gave oral evidence in concurrent sessions on 8, 9 and 10 March 2011. 175Dr Webb is the principal of Stephen N Webb & Associates Pty Limited, Consulting Engineers, specialising in the provision of floodplain management and drainage advice. Dr Webb holds a Bachelor Degree with Honours in Engineering (Civil) from the University of Canterbury, New Zealand and is a Doctor of Philosophy (Hydrology) from the University of New South Wales. He has worked in the area of hydrology for approximately 40 years. Mr Bewsher holds a Bachelor Degree with Honours in Engineering from the University of Tasmania and a Master of Science in Civil Engineering from the California Institute of Technology. Mr Bewsher is the principal of Bewsher Consulting Pty Limited which specialises in the area of hydrology including floodplain risk management and design and management of flooding and drainage infrastructure projects. Mr Bewsher has been working in the area of hydrology/hydraulics for the past 34 years. 176Dr Webb has been visiting the Land since 2003 and has taken many photographs of the Land over that period. He has reviewed Parish Maps and aerial photography together with topographic information to analyse the change in the Land over time. He has also collected daily rainfall data from the Bureau of Meteorology and has analysed surface water levels and groundwater levels from information along a transect that ran from the southern point of the open drain (gauge SW9) to the north across Turnock Street and past gauge SW4 to gauge GW1 ("SW" denoting surface water and "GW" denoting groundwater). The water level measurements from the gauges along the transect are collated in Figure E2 of Dr Webb's August 2010 Report. Dr Webb has also analysed groundwater in a number of piezometers in the Land and collected water quality data from 2003. 177Dr Webb referred to "flood studies" for the Tweed River that have been carried out by the defendant in response to flood and development pressures along the Tweed River. He formed the opinion that the drainage system in respect of the area and in particular in relation to the Land functioned well until the main drainage paths became obstructed by development in the area. Dr Webb expressed the opinion that the filling of the land in the vicinity of the Bowl's Club and the Nursing Home caused the initial drainage problems by blocking a major natural drainage path, the Natural Watercourse, northwards from West Kingscliff to the Tweed River. 178Dr Webb was critical of Mr Findlater's drainage study. He claimed that it failed to correctly and clearly show the existing drains at the time the study was done and that the catchment area he used for calculating inflows to the 1200mm pipe was about half of the actual catchment (as pointed out by Mr Hill and agreed with by the defendant in its correspondence). Dr Webb was also critical of the defendant's acceptance of Mr Findlater's proposal or recommendation for a detention basin on the Land to solve the problem caused by the development of the NPE blocking the Northern Drain. Dr Webb claimed that solving a drainage problem in this fashion was "not good drainage practice". His opinion also included the following: In fact it would not been [ sic ] found in any practice manual for drainage unless the affected landowner was properly compensated after acknowledgment of the problem. ... The permanent blocking of the Northern Drain (or equivalent) by this decision meant that the Subject Land and adjoining properties wetted up. The 1200 pipe could not meet the drainage needs for the area even for low flow. After adopting the detention basin "solution", Council persisted with seeking approval for the detention basin from Gales (which was not forthcoming). Council letters throughout this period said that there was no need to take any further action on drainage until the Subject Land was developed, as the unfilled land provided adequate retention for now. They then compounded the drainage problem, at least as far as the Subject Land is concerned, by constructing Turnock Street/Elrond Drive with inadequate drainage structures. This was despite sensible advice to Council by the consultant designing Turnock Street (Ray Sargent & Associates (RSA)) that adequate drainage needed to be provided, and such drainage was dependent upon the "Ultimate" drainage scheme (involving a "Future open drain (as per WBN study)"), which even at that time (1996) RSA showed on their sketch. 179Dr Webb analysed the collected data in relation to surface water and groundwater levels north and south of Turnock Street. From that data he claimed that he was able to establish a relationship between ponding duration north of Turnock Street and rainfall assisted by land-based photographs taken at regular intervals. He used that relationship to assess the pattern of dry periods and wet (ponded) periods north of Turnock Street on the assumption that the culvert under Elrond Drive was properly maintained and that there was a reasonable opportunity for surface runoff to drain to that culvert via a shallow table drain. Dr Webb established that there would have only been 7 periods of summer ponding lasting six weeks or more in the period from 1989 to mid 2010. Dr Webb concluded that three of the ponding periods had been in the 4.5 years prior to mid 2010 that were unusually wet (except for 2007). 180Mr Bewsher referred to the topography of the Land and concluded that following local rain and ponding, water would be present for long periods, weeks and sometimes months, and would gradually diminish as a result of evaporation and infiltration. Mr Bewsher said that he would agree that some slow drainage would occur in north-westerly, westerly and southerly directions to other areas if the ground level was lower. Mr Bewsher accepted that during local catchment flooding when the capacity of the 1200mm pipe was exceeded, a portion of the flood flows that may have otherwise travelled in a generally east-to-west direction would likely have been directed to the south across the Land. Mr Bewsher concluded that those flows would have then joined with other flows travelling across the Land. He expressed the opinion that additional low-level culverts under Turnock Street would have increased the potential for the Land to drain. Increase in stormwater runoff 181There does not seem to be any issue in these proceedings that the amount of stormwater coming onto the Land has increased. In this regard Talbot J in Gales Holdings Pty Limited v Tweed Shire Council [2006] NSWLEC 85 said at [6] that urban runoff onto the Land had increased "significantly over recent years as a consequence of the closing off of the main flow path to the north and west". 182Mr Bewsher accepted that the increase has "certainly" been "significant" and had largely come from a change in the catchment area to the north flowing onto the Land (tr 456). Dr Webb calculated it at 200% or three fold from the northern sub-catchments between 1974 and 2009. Dr Webb expressed the opinion that the increase had occurred because the northern sub-catchments did not previously drain onto the Land north of Turnock Street because there was a capacity for the water to flow into the Natural Watercourse prior to the development in that area. Once the development of the Bowl's Club, NPE and Kingscliff Beach Estate occurred the stormwater runoff onto the Land increased. This was to be expected because the area of sub-catchments draining onto the Land had increased by a factor of three. 183I am satisfied that between 1974 and 2009 there has been a 200% increase in the quantity of stormwater draining onto the Land from the northern sub-catchments. The adequacy of the 1200mm pipe 184Prior to the blockage of the Northern Drain the stormwater from the north in Catchments 1B, 1C, 1D and 1E (as identified in Schedule A to this judgment) flowed down from the north and the Bowls Club but had "a good drain off" to the west, through the Northern Drain (tr 450). In the early 1990s NPE and Kingscliff Beach Estate (further to the north) were under construction and there were earthworks at the Bowls Club. The Eastern Drain was also filled in as part of the NPE development (tr 451). By the time the Northern Drain was filled the only flow path for the stormwater runoff out of the northern region was the 1200mm pipe. There was a small branch drain coming into the 1200mm pipe from the Nursing Home area at the western end of the pipe. 185The plaintiff's case is that the 1200mm pipe was not an adequate alternative to the Northern Drain and that this inadequacy was a cause of the increased flow of stormwater runoff onto the Land. The defendant submitted that it has not been demonstrated that the 1200mm pipe is, or could sensibly be anticipated to be, any less effective than the Northern Drain in draining the Land on a day-to-day basis. 186The Joint Report of Dr Webb and Mr Bewsher of 22 January 2011 included the following agreement pertinent to this issue: 33. The experts agree that the filling and development of land to the west and north-west of the Site and the provision of only a 1200mm pipe has meant that at the current time, a significant portion of the local catchment flood flows are diverted south through the Site, once flood levels in the general vicinity of the 1200mm pipe reach a level of about 0.9mAHD. 187However Mr Bewsher expressed the opinion that the 1200mm pipe provided the same measure of drainage as previously provided by the Northern Drain (tr 481). Mr Bewsher's opinion was based on the premise that there was no available description or detail of the level or size of the Northern Drain, except for what he could find in a document referred to as "Figure 5" included in his report dated 2 December 2010. Mr Bewsher described "Figure 5" as "an old undated plan" which he labelled "Plan of Levels and Ground Features at North-Western Corner of Subject Site (Circa 1990)". That label is in issue. 188When Mr May's description of the Northern Drain at the time he went fishing in it in 1978 and 1991 was drawn to Mr Bewsher's attention (tr 479), he said that he had some difficulty with that description when he compared it with what is in Figure 5. The dimensions of the Northern Drain described by Mr May were not the subject of any challenge and I accept his evidence that he went fishing on that particular drain both in 1978 and in 1991. Mr Bewsher made the point that Mr May's evidence did not make clear whether the dimensions that he described were at that part of the Northern Drain immediately adjacent to the Land. In those circumstances he suggested that the "key issue" was the level of the Northern Drain at the boundary between the north eastern corner of the NPE and the north western corner of the Land. Those are reasonable observations in the circumstances because Mr May's evidence was that he travelled up the Northern Drain about a third of a kilometre and there is no evidence of the precise distance between the Chinderah Drain and the point at which the Northern Drain meets the Land. 189Dr Webb expressed the view that Figure 5 shows the Land and the position of the Northern Drain at the time that the flows of water were diverted around the NPE during the filling of the NPE. He expressed the opinion that Figure 5 depicts a relatively recent man-made network of drains in that location. Dr Webb based this conclusion on the "regular size" of the drains as depicted in Figure 5 both on the northern and eastern boundaries of the NPE. He emphasised that prior to the development of NPE the Eastern Drain joined up with the Northern Drain and he expressed the expectation that the Northern Drain would be of the dimensions described by Mr May "right to the corner of" the Land, at the entrance point of the 1200mm pipe. 190Irrespective of this disagreement there is no issue between Dr Webb and Mr Bewsher that before the stormwater would flow south onto the Land, the level of the water at the invert or mouth of the 1200mm pipe would have to reach 0.9m AHD. 191I am not satisfied that Figure 5 depicts the true position or dimensions of the Northern Drain prior to it being filled by Baclon in developing the NPE. Dr Webb expressed the opinion that absent the Northern Drain the smaller drains "could not contain the existing flows" and could not accommodate the rapidly increasing flows. He described the 1200mm pipe as "grossly inadequate". His oral evidence was (tr 503): So a pipe that doesn't carry the flow can't even get into on a lot of occasions, and even when it tries to get in not very much can get in, is not the adequate replacement for anything, in my view. 192Both Dr Webb and Mr Bewsher were assisting the Court in difficult circumstances where there was a lack of photographic evidence or contemporaneous documents relating to the filling in of the Northern Drain and the establishment and construction of the 1200mm pipe. However Mr Henley's note of his conversation with Mr Findlater on 15 March 1994 and the correspondence between Mr Hill and the defendant soon after the 1200mm pipe was installed is of some assistance on this issue. Mr Hill referred to the ponding along the boundary line and claimed that the 1200mm pipe was "under capacity" to cater for stormwater runoff. Mr Hill claimed that his client's land was thereby subjected to a greater degree of flooding than would have occurred prior to the construction of NPE. There is also the defendant's letter to the local resident in response to a complaint about drainage problems on 21 January 2003 in which it made the admission that the drainage system had been "rendered inadequate" by development in the area over the years. This admission is more general in its terms and not specifically related to the 1200mm pipe. However it is a matter that is to be taken into account generally when considering this issue. 193With the assistance of the contemporaneous documents and to a lesser extent taking into account this general admission I am satisfied that Dr Webb's opinion is to be preferred. I do not accept that the 1200mm pipe provided the same measure of drainage as previously provided by the Northern Drain. I am satisfied that there was additional stormwater runoff flowing onto the Land that would not have otherwise flowed onto the Land had the Northern Drain not been filled and had the 1200mm pipe been adequate. It is not possible to identify the precise extent of that additional stormwater runoff. However I am satisfied that the 1200mm pipe did not replicate the same drainage capacity that was in place prior to the filling in of the Northern Drain and Baclon's failure (conceded by the defendant) to comply with condition 43 of the Development Consent. Turnock Street 194The plaintiff claims that the defendant's conduct in constructing Turnock Street without any culverts at ground level created an impediment to stormwater runoff flowing away from the Land. It claims that this contributed to the wetting up of the Land such as to constitute a nuisance. 195The construction of the culverts half way up the embankment of Turnock Street appears to have been in anticipation of the plaintiff filling the Land. However the question of the adequacy of the drainage of the stormwater runoff from the Land after the construction of Turnock Street is to be considered in the circumstances as they exist rather than in the circumstances as they might exist should the plaintiff fill the Land. 196There is no real issue between Dr Webb and Mr Bewsher that Turnock Street blocked the south-westerly flow of water from the Land so that it then flowed in a more westerly direction to the Elrond Drive culvert. They agreed that the groundwater levels to the north of Turnock Street are on average higher than the groundwater levels to the south of Turnock Street. However they disagree on the cause of the higher levels north of Turnock Street. 197The relevance of the level of groundwater is that when the level is elevated it is more difficult for water/stormwater runoff to infiltrate the ground and ponding is likely to occur. It is also relevant as to the length of such ponding. If there is a sustained elevation in the level of groundwater it will be more difficult for the surface water to infiltrate the ground over longer periods and thus there will be longer periods of ponding. Dr Webb and Mr Bewsher agreed that if the groundwater table has risen close to the surface very little rainfall is required to maintain ponding on the surface of the Land. 198Both experts agreed that the gradient of the Land is north to south. Dr Webb expressed the view that since the construction of Turnock Street the flow of the water south on the Land is a much longer torturous path at a lower flow rate with the consequence that the water has longer to infiltrate the ground and raise the groundwater level. Dr Webb's analysis of groundwater levels during the period 25 October 2007 to 8 September 2009 is depicted in Figures E3 to E7 of his Report of August 2010. The average of the groundwater levels during that period is depicted in Figure E3. Dr Webb reported as follows [8.3.7]: It can been seen that the groundwater surface is essentially horizontal through Turnock Street to the north and then drops off steadily to the south in the direction of the South Westerly Drain. I attribute this behaviour to one of two alternatives - it is because either construction of Turnock Street created a groundwater barrier preventing groundwater flows to the south, or the surface flow barrier created by Turnock Street forced groundwater recharge north of Turnock Street artificially raising the groundwater level in this location. From either viewpoint, Turnock Street artificially elevates groundwater levels north of Turnock Street even with the tabledrain in place. 199Dr Webb also analysed the results of the readings from piezometers installed in the Land from June 2003 to February 2010. Those results are depicted in Annexure F "Other Groundwater Observations" to Dr Webb's Report of August 2010. The "elevation data" collected from the two piezometers located north of Turnock Street (SP2N and SP3N) are depicted in graphs attached to the Report. Mr Bewsher did not comment on these particular readings although he said he "had a look over them" (tr 570). 200Mr Bewsher did not perform any comparable analysis of groundwater levels but disagreed with Dr Webb's analysis. His evidence was that the reason the groundwater levels in Dr Webb's Figures E3 to E7 are lower on the southern side of Turnock Street is because of the drains that have been constructed in that area enabling the surface water to flow away to the South-Westerly Drain (tr 551). He gave the following further evidence (tr 551-553 and 595-596): Q. But doesn't that tend to suggest then that the groundwater level on the high side has been increased by reason of the construction of Turnock Street because there aren't any drains except for the table drain? A. I think the issue is that at the time Turnock Street was constructed were these table, extra drains we see on the southern side present or not. My understanding is they were not present at that time. Q. That is what I am saying. It suggests to me that when you look at the analysis that Dr Webb has carried out, the groundwater levels on the northern side of Turnock Street are obviously higher in the main than on the right-hand-side, the southern side. A. Yes. Q. On the southern side there is the capacity to drain away by reason of the construction of the drains. A. Yes. Q. There is now the capacity on the northern side to better drain away with the table drain. A. Yes. Q. But as you have said that is still not the ideal. Doesn't it suggest that by reason of the absence of the drains on the northern side the level of the groundwater as observed on the northern side that the factor that caused it to increase to be higher than the southern side is the presence of the construction of Turnock Street? A. Your Honour I maybe put it slightly the other way, the reason why it is lower on the other side is because the table drains were constructed, subsequently constructed there. If those table drains, a great network of drains had been constructed within the subject site it wouldn't have been. Q. I don't have a chart that tells me what the level of the groundwater was prior to the time of the construction of Turnock Street. A. No your Honour. Q. But on this analysis do you suggest that Turnock Street has no impact on the level of the groundwater? A. It has an impact to the extent that, and maybe it's not an impact but when the table drains were constructed on the south-western side when they came up to Turnock Street they stopped, as opposed to continuing through. But I am not sure that that's necessarily as a result of construction of Turnock Street, it is just-- Q. A consequence, has to be a consequence, doesn't it, if the water can't get away and if it flows ever so gently to the right, if it can get away in a drain we see the evidence that the groundwater will be less, we see that on the southern side. A. Correct. Q. The increase in water on the northern side, it follows doesn't it, with the incapacity to get away is likely to increase the groundwater level? A. Increase the groundwater? Q. Level of the groundwater. A. Are you postulating your Honour a situation where the table drains on the southern side of Turnock Street had been constructed and Turnock Street hadn't? Q. No, I am just asking you what your opinion is hydrologically in respect of water flowing on to the land not being able to get away as it used at Turnock Street having an effect on the level of the groundwater by reason of that factor, that it can't get away the way it used to get away and it ponds. A. Yes, I understand. I believe that the construction of Turnock Street itself and the compaction that would have taken place underneath, which gets back to the first of the two reasons, may have had an impact, though I believe it would be very minor because it is underlying sand. I don't believe that these diagrams demonstrate what you have put to me. Q. I am not referring to the diagrams, I am just asking you your opinion as to whether the water, increased water-- A. Understood. Q. --and the lack of capacity for it to get away would have had hydrologically a probable impact on the level of the groundwater. A. Yes, my answer is I believe there is more water, the site is wetter, the extent of ponding on the northern side of Turnock Street would have been marginally higher. It is my opinion that it wouldn't have had any material impact on the groundwater, was unlikely to have had any material impact on the groundwater and I see no evidence from Dr Webb's transect information that that is actually what has happened. Q. Why do you say that? A. Because the diagrams that he has produced, the blue diagrams I believe illustrate how an effective drainage system, if probably (sic) constructed, could lower groundwater levels in the area. They don't demonstrate the impact caused by the construction of Turnock Street at all. Q. Have you seen evidence of the changes in the groundwater Mr Bewsher? A. The only groundwater information we have in relation to the subject site, the majority of it, is in these diagrams and in the table of information. There is some piezometer records that Dr Webb presented in his report but principally it is this information in annexure E I believe. ... Q. If you have an increase above what is usually or had usually been on the land do you say that it can affect the groundwater or not? A. I do your Honour. Q. So that if there is an increase in the volume of water coming on to a site it can affect the level of groundwater. A. Yes and I have in my statement said that I believe the site has got wetter. Q. Yes and you said that yesterday afternoon, in your evidence you said it is wetter and the extent of ponding would thereby have been marginally higher but you also said that it was your opinion that there had been no material impact on the groundwater and I am trying to just analyse what your position is. A. Understood. Q. You say, do you, it can have effect on the groundwater? A. Yes. Q. But in this instance it did not? A. Yes, that's correct. 201Mr Bewsher was asked about the relationship between the level of groundwater and ponding and said (tr 567): If the groundwater level was actually above the bottom of the pond that we're talking about, then the water from the groundwater will be seeping into the pond and so, in that case, the groundwater level will be delivering water to the ponds. If the groundwater stays up at that level for six weeks, for that period of six weeks the water in that pond will be coming from the groundwater entirely. 202The propositions for which the plaintiff contends include that: (1) there was an inability for the increased stormwater on the Land to flow away as it did prior to the construction of Turnock Street; (2) the groundwater levels north of Turnock Street increased by reason of the Land becoming wetter because of the inability for the increased stormwater to flow away; and (3) this caused ponding in the area north of Turnock Street from time to time. 203The defendant submitted that there is no evidence that the groundwater levels north of Turnock Street in 2003 were any higher than in 1992. The defendant submitted that Mr May's evidence establishes that the groundwater levels in the area north of where Turnock Street was constructed were very near the surface when Mr May observed the Land in 1991/1992. Mr May encountered a large pond north of Turnock Street when the Land appeared otherwise to be dry. Mr May's evidence was that there was a wet area north of Turnock Street, probably in Lot 12, and that the water came up to just below his knees. He also described this as a "natural depression". The defendant also relied upon Mr Murray's survey for the defendant in 1992 in which he recorded "shallow standing water" being present over a large part of the Land in particular in an area north of where Turnock Street now is. 204Dr Webb accepted that groundwater levels were high between 1989 and 1993 prior to the construction of Turnock Street and attributed the elevated water levels to poor performance of the drains that serve to facilitate the flow of water away from the Land. The defendant submitted that whilst this may be the case it raises two insuperable difficulties for the plaintiff. It was submitted that it renders neutral all of the anecdotal evidence of a dry site in the period prior to the construction of Turnock Street because the observations that the site appeared to be well drained encompassed periods of years during which it is known that the groundwater level was high enough to create ponding. The second is that Dr Webb's evidence establishes very clearly that there was a range of significant drainage problems on the site not associated with the construction of Turnock Street or the inadequacy of the 1200mm pipe that were remedied in 2004 by the creation of the table drains. 205The defendant submitted that a further difficulty for the plaintiff's claim that Turnock Street has influenced the groundwater levels to the north of Turnock Street is that the elevation recorded by Dr Webb is uniform along the northern half of the transect. Groundwater levels are not elevated adjacent to Turnock Street where the additional ponding is alleged to be occurring. It was submitted that no explanation has been proffered to link the alleged elevated groundwater level 200 metres north of Turnock Street with the diversion of flows at Turnock Street. 206Mr Bewsher agreed that the changes in drainage caused by the filling of the Northern Drain and the construction of Turnock Street would result in additional ponding immediately on the northern side of Turnock Street. He did not dispute that the surface water was being diverted but he did not believe that it would "make much difference at all". 207I do not regard these as insuperable difficulties for the plaintiff. On the basis that the anecdotal evidence is given little weight, the fact that there were significant drainage problems prior to the construction of Turnock Street means that the construction of Turnock Street with no drainage would compound the problem. There is no direct evidence of the level of groundwater during specific periods prior to 2003. Assuming the groundwater levels were high prior to the construction of Turnock Street, I am satisfied that the construction of Turnock Street had the impact of increasing those levels because there was less opportunity for the surface water to flow away as it did prior to its construction. 208There is no issue between the two experts that the construction of Turnock Street has made the Land wetter. The reason for that is a lack of capacity for the water to flow under Turnock Street with the necessity for the water to flow to the south west to escape through the Elrond Drive culvert. I accept Dr Webb's evidence that the flow of the water was slowed by reason of the construction of Turnock Street without ground level culverts. I also accept Dr Webb's evidence that the path of the water flow and the rate of the water flow caused the Land to become wetter with a consequence that ponding occurred. I prefer the evidence of Dr Webb in relation to the impact of the construction of Turnock Street on the wetting up of the Land and the higher levels of groundwater to the north of Turnock Street. 209The natural flow of the stormwater through the Land was diverted to the south west by the construction of Turnock Street. It was not possible for the stormwater to drain at Turnock Street other than through the Elrond Drive culvert. I have no doubt that had the defendant constructed culverts at ground level the stormwater runoff could have drained through those culverts. I am satisfied that the culverts as constructed were inadequate for the draining of the stormwater runoff from the Land. I am also satisfied that the construction of Turnock Street impeded the efficient drainage of the stormwater runoff from the Land. Elrond Drive culvert 210The original drawings produced by Ray Sargent on 29 July 1996 in relation to the construction of Turnock Street proposed three 1500mm pipes in the vicinity of the Elrond Drive culvert. Notwithstanding the covering letter advising on construction of three 1500mm pipes, the defendant constructed only one 900mm pipe through which the stormwater runoff could drain from the Land. 211Dr Webb expressed the opinion that the blockage of the culvert in 2003 was the principal cause of the ponding at that time. Mr Bewsher acknowledged that whilst the blockage of the culvert "would have caused ponding, inadequate maintenance of the downstream drain leading from the pipe, could also have caused ponding". 212It may be that the Elrond drive culvert would have been adequate had there been culverts under Turnock Street at ground level. However I am satisfied that the single 900mm culvert under Elrond Drive in the absence of culverts at ground level under Turnock Street, with the increase of the stormwater runoff onto the Land, was inadequate to allow that stormwater runoff to flow off the Land without ponding. Ponding 213The experts sought to identify wet and dry periods to assess the likelihood of ponding at particular times and particular periods. As I have already outlined the plaintiff's case is that the wetting up of the Land was caused by the defendant's conduct and one of the consequences of the wetting up of the Land was the creation of the ponding suitable for breeding of Wallum Froglets. The type of ponding suitable for the breeding of Wallum Froglets is "ephemeral ponding" defined by Dr Webb as a "closed depression that temporarily stores surface water for a defined period. It may be at a low topographic level and sustained at least partly by groundwater, or it may be more elevated and sustained by regular surface water inflows, have a semi-impervious base, and could be sustained partly by a perched (or locally elevated) water table". Ephemeral ponding is to be understood to be for a period of six weeks or more in summer. 214Dr Webb used the measured wet and dry periods from available records for the period 2007 to 2010 to derive relationships between rainfall and observed wet and dry periods and then applied those relationships to predict the wet and dry periods from 1989 to 2010 based on certain assumptions. Dr Webb used the surface water level observations across the transect, and in particular the readings in the shallow pond at SW4 to assess the frequency of ponding north of Turnock Street. He collected daily rainfall data from the Bureau of Meteorology website and plotted it in six-month blocks. He then plotted the observations at SW4 commencing on 25 October 2007 up to 1 July 2010. The period over which observations are available at this site was used as the "calibration period". Relationships between rainfall and water level were obtained for that period by considering the wet and dry periods and the rainfall distribution. On completion of the calibration period analysis and plotting of the wet and dry periods, the photographs of the area were used to check the calibration. Dr Webb assumed that the Wallum Froglet required a period of about five to six weeks to metamorphose in summer and a longer period of up to six months at other times. 215Dr Webb concluded that between 1989 and 2010 there were only seven periods of six weeks or more of ponding north of Turnock Street: one period in each of the years 1990, 1994, 1999, 2003, 2006, 2007 and 2009. He concluded that there was one period of six weeks ponding in winter in 1998 and one period of nine weeks ponding in the winter of 1999 with further periods in the winter of 2008 of 11 weeks and 3.5 months in 2009. 216Mr Bewsher made a number of criticisms of Dr Webb's analysis. The first was the suggestion that SW4 (a surface water gauge in the transect north of Turnock Street) "may not be" representative of site ponding except when levels rise above the local undulations around it, and identified a measure of 0.8m AHD. Dr Webb answered this criticism by observing that SW4 is one of the lowest points in the landscape immediately north of Turnock Street and relatively distant from the Elrond Drive culvert and the table drain. He observed that it is one of the last local depressions to dry up and that when it is dry there is no extensive ponding left immediately north of Turnock Street. 217Mr Bewsher's next criticism was a suggestion that there are number of anomalies or inconsistencies in the water level records presented by Dr Webb. He identified five dates around which he claimed the inconsistencies in the SW4 water levels occurred. However he later removed four of those dates, identifying them as "outliers" for the purpose of his proposed model, leaving only one on 20 October 2008. He claimed that such an anomaly may be a measurement error at SW4. Dr Webb answered this complaint by stating that the SW4 data for that date was consistent with the behaviour of the other data points along the transect. 218Mr Bewsher's next criticism was a suggestion that rainfall records used by Dr Webb were not representative of conditions on the Land. Dr Webb used the rainfall recorded at Tweed Heads, about 7 km from the Land, and compared that data with the rainfall data at the Bowls Club (up to 2008) and found "very good consistency". Dr Webb conceded that there would be some variability with smaller storms and accepted that the observed rainfall on those days may not be the same as that which occurred on the Land. 219Mr Bewsher's next criticism was a suggestion that inconsistencies might be due to changes in groundwater levels. Dr Webb observed that changes in groundwater levels tend to be related to rainfall but on a longer term basis than surface ponding. He observed that Mr Bewsher's new model (referred to below) ignores groundwater and he therefore could not see this as a constraint. Mr Bewsher also referred to changes in ground levels near SW4. Dr Webb observed that the water level was measured relative to a fixed stake and he could not see how this would have introduced any errors. He did not observe any other factors that could have affected the ground level at SW4. Mr Bewsher also referred to changes in vegetation (affecting evapo-transpiration) as a possible cause of inconsistency. Dr Webb's response to this was that there was little vegetation in or near SW4 and "certainly insufficient to cause any significant variation in evapo-transpiration". 220Mr Bewsher also complained that Dr Webb failed to include any specific duration associated with the rainfall. Dr Webb responded to this complaint by observing that in this regard judgment is required. He said that rain tends to occur in bursts and when looking for bursts he did not generally extend the duration beyond one week because by that time the first day of the rain would have receded. Mr Bewsher also claimed that Dr Webb ignored any rainfall less than 60mm. Dr Webb suggested that this claim is incorrect because 60mm was the trigger in his study for the change from dry periods to wet periods but that any ongoing rain after that was in fact considered. Mr Bewsher also claimed that Dr Webb had taken no direct account of infiltration or evaporation. Dr Webb observed that his assessment was based on observations of water levels and rainfall and that infiltration is dependent on the properties of the soil and the level of the groundwater table. He said that water levels vary due to the input of rainfall and the losses due to infiltration and evaporation. Accordingly he implicitly took them into account but did not let them vary throughout the year. 221Mr Bewsher also complained that Dr Webb failed to take any direct account of smaller follow-up rainfall. Dr Webb claimed that this was also incorrect because follow-up rainfall was allowed to extend the wet period if it was significant. 222Mr Bewsher also complained that Dr Webb did not simulate SW4 directly. Dr Webb said that this is partially true but that it was not the purpose of his assessment. His purpose was to establish the frequency of 6 week ponding periods in summer under the current drainage and topographic conditions. It was the duration of the ponding that was critical, not the precise level of SW4. 223Mr Bewsher's next criticism was that Dr Webb failed to consider antecedent rainfall and the water level at SW4 prior to the onset of rainfall. Dr Webb said that this was incorrect. He observed: After a dry period I found that a certain minimum amount of rainfall was required to commence ponding. This is analogous to the "initial loss" commonly used in hydrologic models. Ongoing significant rainfall was allowed to extend the duration of ponding thus allowing for antecedent conditions. A further factor is that once the ponding level dropped below the cessation of flow line thus inducing a dry period, very little time was required for SW4 to in fact become completely dry. 224Mr Bewsher also observed that "two operators of [Dr Webb's] procedure will likely get different predictions". In response Dr Webb observed: Once the assessment criteria were established it was remarkably easy to carry out the empirical assessment. The initial assessment was carried out by one of my staff. I then checked it and found that I needed to make very few changes. The issue that caused the most changes was in determining when follow-up rain was sufficient to extend the period of ponding. 225Mr Bewsher concluded as follows: 19. Hydrology is not a precise science. All hydrological models are to some extent only approximations of reality. It is normal to include assumptions and other approximations in such modelling. The key issue is whether the uncertainties that these create, make the predictions of any value. Expressed another way, is the model 'fit for purpose'? 20. In my opinion, the Court can't be confident that Webb's procedure is 'robust', i.e. one can't be confident that it will produce reliable results outside the 2 year calibration period. 21. Further given the nature of the procedure, it's difficult to test the sensitivity of the procedure to different assumptions about the 'cessation of ponding' level. 22. It is not possible to prepare normal statistical measures of the 'goodness of fit' for this procedure (as would usually be undertaken for a hydrological model). 23. I have analysed the statistical correlation between the observed SW4 water levels records over the 2 year period ... What this shows is that SW4 levels are more highly correlated to the number of raindays rather than the rainfall itself. The implications of this are that it's not just the quantum of rainfall that's important to ponding at SW4, but it's the way that the rain is temporally distributed that is crucial in predicting behaviour at SW4. In my opinion this significantly limits the accuracy of Dr Webb's procedure and confirms the reservations I expressed in my original Statement that there may be a large uncertainty in the predictions he has provided. 226In response Dr Webb observed: I disagree that my Empirical Assessment is not robust. I carried out informal sensitivity tests in setting up the criteria. The "model" is fit for the purpose. Somewhat surprisingly ... Mr Bewsher gets exactly the same number of 6 week summer ponding events in the period of assessment as I did. 227Mr Bewsher had originally proffered what was referred to as the "Pocket Model" for the purpose of predicting the periods of ponding on the Land. He later adopted a model referred to as the "SW4 model". Mr Bewsher explained that the Pocket Model was a "quick and easy simulation of what might happen" in relation to ponding if there are impermeable layers in the soil. He gave evidence that he did not know whether they existed or not although he accepted Dr Hazelton's opinion in the Joint Report dated 3 March 2011 (Ex PD4) that there was high degree of permeability in the soil (tr 610). I am not really assisted by the Pocket Model because the evidence does not support the assumption upon which it was based. Indeed Mr Bewsher described the SW4 Model as a "much better model" (tr 612). 228The SW4 model was described by Mr Bewsher as approximating the physical processes on the Land including rainfall, evaporation, infiltration and spill from the SW4 area. It uses daily rainfall and evaporation records and produces daily estimates of the water level at SW4. Mr Bewsher then used the model to hindcast 1989-2007 water level behaviour. 229From the SW4 model Mr Bewsher predicted ponding periods of 6 weeks or more over the period as follows at 0.68m AHD: 1 in the years 1988/89, 1990/91, 1991/92, 1993/94, 1994/95, 1995/96, 1998/99, 1999/00, 2008/09, 2009/10, and 2 in 1989/90. He predicted fewer periods at 0.70m AHD: 1 period in 1988/89, 1989/90, 1990/91, 1991/92, 1993/94, 1994/95, 1999/00, 2009/10; and fewer again at 0.72m AHD: 1 period in 1988/89, 1989/90 1990/91 and 1993/94. 230Dr Webb was critical of Mr Bewsher's SW4 model. He said it is a "mathematical model" often referred to as a "black box" in which the inputs (rainfall, etc) are converted to outputs (the level at SW4) with very little known of what happens in the "box". Dr Webb expressed the opinion that even if such a model provides a good prediction of the outputs from the inputs, it is "dangerous" to use such a model to predict outputs beyond the calibration period. He emphasised that his own approach did not involve a mathematical model and claimed that Mr Bewsher's SW4 model had a number of flaws including: (1) it fails to consider the impact of the groundwater table; (2) it fails to relate infiltration to the position of the groundwater table; (3) the coefficient for infiltration bears no relationship to the actual properties of the soil; (4) it fails to consider the relationship of the soil moisture store to the initial level of the groundwater table; and (5) the mathematical weighting of 10 given to the "dry" readings at SW4 is entirely arbitrary. Dr Webb claimed that the SW4 model could not reliably be used outside the period against which it was calibrated. 231As can be seen by the comparison between the experts' predictions of ponding, Mr Bewsher predicted far more periods of ponding prior to the construction of Turnock Street in 1997. Dr Webb predicted two periods, in 1990 and 1994, whereas Mr Bewsher predicted eight periods over the period 1988 to 1996 (at 0.68m AHD). The only years in which both experts predicted ponding prior to 1997 was when Dr Webb predicted one period in 1990 and 1994 and Mr Bewsher predicted two periods in 1989/90 and one in 1993/1994. After 1997, Dr Webb's analysis showed five periods of ponding between 1999 and 2010 and Mr Bewsher's analysis showed only four periods of ponding. After 1997 they both predicted one period of ponding in the year 1999/2000 and one in 2008/2009. In the whole period Dr Webb concluded that there would have been seven periods of ponding and Mr Bewsher concluded that there would have been twelve periods of ponding (at 0.68m AHD) or eight periods (at 0.70m AHD) or four periods (at 0.72m AHD). Mr Bewsher's Pocket Model concluded that there would have been thirty nine periods of ponding, twenty five before the construction of the Turnock Street and the balance after its construction. 232The Joint Report (Ex PD4) dated 3 March 2011 included the following ("SW" in this context refers to Dr Webb and "DB" refers to Mr Bewsher): SW provided further information to DB by email on 3 rd March 2011 as set out below for the 21 year period from 1989/90 to 2009/10. This information provide estimates of ponding frequencies under different scenarios which SW did not consider in his original assessment: Cessation of Ponding Level 0 .7 mAHD Original = 7 summer ponding events of 6 weeks or more (DB = 7) 5 week ponding = 8 summer ponding events of 5 weeks or more (DB = 9) 4 week ponding = 17 summer ponding events of 4 weeks or more (DB = 14) Cessation of Ponding Level 0.68 mAHD (6 weeks ponding or more) 10 summer ponding events of 6 weeks or more (DB = 11) Cessation of Ponding Level 0.72 mAHD (6 weeks ponding or more) 4 summer ponding events of 6 weeks or more (DB = 3) SW & DB agree that the ponding frequencies set out above for both approaches are essentially the same, even though SW & DB disagree with the methodologies used by the other. 233In the concurrent session of evidence on this topic on 10 March 2011 Dr Webb said (tr 617): Anyway, I took the current relatively well-drained conditions and I took the rainfall period. My purpose was to find, for a six week period of summer ponding, how many occurrences were there. That was my objective. That's what I did. And I got 7. Mr Bewsher, with his what I call a black box model - I am not being impolite in using those words. It sounds like I am but that is the terminology if you have something in between an input and an output and you have things happening in it. I also suggest he does not have enough things happening in it, because he does not have enough information. That is why it is a black box. But you have an input and an output. He also got 7, as you see from our joint report. Certainly, what I was trying to do was find the number of occurrences. We essentially get the same number. So, I do not agree with his model at all. He quite clearly does not agree with my model, but we do get the same answer. During the course of conferencing, I did a quick assessment, because he has looked at four week and five week periods as well. I did a quick assessment of those. They have not been fully checked. Once again, I found that I got similar answers to his approach. So, in the end, I suppose, I do not "care". That is probably not the right word, but we are both getting the same - to assist the Court we are getting the same answers and that is what we have written in our joint report. 234The plaintiff urged caution in accepting that where each of the experts predicted a ponding period in the same year, the ponding period was more likely to have occurred. The plaintiff submitted that such reasoning overlooks the manifest problems with the SW4 model and Dr Webb's detailed concerns with it. It was submitted that where the opinions of Dr Webb and Mr Bewsher differ, Dr Webb should be preferred. The plaintiff propounded a number of reasons for this preference including: (1) that Dr Webb had visited the Land over several years and had the opportunity to observe first-hand the operation of the hydrological processes affecting the Land and the existence of ponding over extended periods, whereas Mr Bewsher's only encounter with the Land was three visits over a three-month period; (2) that Dr Webb meticulously used a range of materials, including voluminous aerial photography, topographic data, rainfall data and direct measurements of water levels and water quality to assemble a history of changes to land use and catchments since the Land was in its natural state to ascertain flow paths, groundwater and the effect of pollution from run-off, whereas Mr Bewsher did no such thing; (3) that Mr Bewsher had apparently discarded his Pocket Model and had failed in cross-examination to properly explain the operation of his new model for "retrofitting" rainfall data; (4) that Dr Webb's criticism of Mr Bewsher's SW4 model was eloquent; (5) that Mr Bewsher failed to take into account groundwater levels and manipulated three coefficients solely for the purpose of retrofitting the curve to levels observed at SW4; and (6) Dr Webb's diagrams of the groundwater levels along the transect which uses a level survey conducted over an extended period provides an indication of the effect of the presence of Turnock Street on groundwater. 235Dr Webb's attention to detail and the care with which he applied his expert knowledge to the voluminous material upon which he relied was extremely impressive. Mr Bewsher was in a much more difficult position because as he put it there was a "great shortage of time" within which to prepare his expert opinion. His first attempt to provide assistance to the Court with his Pocket Model was recognized by him as dependent upon an assumption that may not be justified, and ultimately as I have found above was not justified. Both experts defended their respective methodologies and analysis and I am sure that both were attempting to assist the Court in reaching a conclusion in these difficult circumstances. There is no doubt that each had to apply a level of judgment in making the predictions of ponding over the years. I am satisfied from each of their approaches that on the balance of probabilities ephemeral ponding has occurred on the Land prior to the construction of Turnock Street and after its construction. Quigan Street problems 236The plaintiff's claims in relation to the stormwater outlets in the Quigan Street area have changed over time. However Dr Webb gave the following evidence in relation to the outlets (tr 653-654): I have had the advantage over Mr Bewsher of being able to observe the situation at Quiggan (sic) Street since 2003. There have been several things happening there. One is that the actual head work structure, where the pipes come in, has always been a bit unsatisfactory. I have discussed it with council on a number of occasions. Then it has failed in different ways and it has been repaired, but only repaired in what I would call a stop gap way, or patching. When I visited it in December last year, it had, in my words, completely collapsed. The importance of this is that, in its present state, it is unsafe, I believe, to public risk. And the water sort of flows over the structure and down into the channel, and tries to go further downstream. The other important thing about it is that, historically, there has been a channel below it for a very long time, which may or may not have been developed by the water flowing down, or by efforts to stop the water ponding within the site. Gales, during the period that I have been engaged, did clean out that channel, right down through to the south-westerly drain and, immediately, scouring occurred in the channel, and the sand shifted from the top to the bottom and started to block the channel up again. It became apparent to me - well, it was apparent before but - what we really needed was a structure that collected the water, reduced the velocity, and then the velocity of water coming out of the energy dissipation structure was such that you could maintain a channel before that without scour. To achieve that, the normal process is to have an energy dissipation structure. That's why I suggested at that time that that's what should be installed when the whole structure is re-engineered. I have discussed that with council. ... It is quite a steep drop from where these pipes come in from the road down to the land. Unless you do something, there is going to be a high velocity at the foot of the bank. It is really as simple as that, as I see it. 237There is no issue that this problem exists. The Quigan Street outlets are clearly in disrepair. During the course of the trial it was suggested that the defendant would repair it. I am not aware whether that has occurred at this stage. 238The inadequacy of the 1200mm pipe combined with the construction of Turnock Street without any drainage culverts at ground level, the 900mm capacity of the Elrond Drive culvert and the 200% increase, or the significant increase, of stormwater runoff onto the Land, resulted in what has been described and adopted by the experts as a "bottleneck" of the flow of the stormwater runoff to the south western corner of the Land. The disrepair of the Quigan Street outlets caused an increase in the velocity of the stormwater from the outlets, causing an adverse impact on the Land. 239I am satisfied that the defendant failed to install adequate drainage to enable the stormwater runoff to flow off the Land resulting in the wetting up of the Land and at times ephemeral ponding suitable for the breeding of Wallum Froglets. 240I am also satisfied that if the culverts under Turnock Street had been at ground level rather than approximately half way up the embankment, and if the culverts under Elrond Drive had been constructed in accordance with the advice (i.e. three 1500 mm pipes), the "bottleneck" would not have been created. Vegetation/Soil Issues 241Five experts assisted the Court on vegetation/soil issues: Dr Andrew Benwell, Dr Anne Clements, Mr Andrew Murray, Dr Andrew Smith and Dr Pamela Hazelton. 242Dr Andrew Benwell is a botanist and plant ecologist. He provides consultancy services for Ecos Environmental Pty Ltd and has performed work for state government departments and local councils. He holds a Diploma of Horticulture from the Victorian College of Agriculture and Horticulture, a Bachelor of Arts (Honours) (Biogeography) from the University of New England and is a Doctor of Philosophy in plant ecology from the University of New England. Dr Benwell has been working in his field of expertise for approximately 30 years. 243Dr Clements is a plant ecologist and principal of Anne Clements & Associates Pty Ltd, a company specialising in botanical conservation assessment and the development of conservation strategies. Dr Clements holds a Master of Science degree from Macquarie University and is a Doctor of Philosophy the thesis for which examined the vegetation of sand masses of the mid-north coast of New South Wales. Dr Clements has been working in her field of expertise for approximately 25 years. 244Mr Murray is a botanist and vegetation ecologist with 25 years experience in field surveying and vegetation mapping on the far north coast of New South Wales. He is the principal of AS Murray & Associates and holds a Bachelor of Science (Botany and Oceanography) from the University of New South Wales. 245Dr Smith specialises in eco-system management and biodiversity conservation. He is the principal of Austeco Environmental Consultants. He was an academic for sixteen years in the Faculty of Natural Resources, University of New England. He holds a Bachelor of Science (Honours) degree from the University of Sydney and is a Doctor of Philosophy. Dr Smith has been working in his field of expertise for approximately 20 years. 246Dr Pamela Hazelton, a soil scientist, is the program head, coordinator and lecturer of the Master of Environmental Engineering Management at the University of Technology, Sydney. Dr Hazelton provides consultancy services through PA Hazelton Soil Survey and Investigations Pty Ltd. She holds a Bachelor of Science from the University of Sydney and is a Doctor of Philosophy. Dr Hazelton has been working in her field of expertise for approximately 30 years. 247The experts provided a number of reports being: Dr Benwell of December 2010 and 2 February 2011; Dr Clements of 24 January 2011; Mr Murray of 2 December 2010; and Dr Smith of 27 August 2010. Each of these experts was also a signatory to the Joint Report of 12 February 2011. Dr Hazelton provided a report of 21 January 2011 (and her Joint Report with the Hydrologists of 3 March 2011). Evidence was given in concurrent session on 11 March 2011. 248Although the evidence of the vegetation and soil experts during the concurrent session was addressed in accordance with an agreed agenda for discussion, the real issue for determination is whether the wetting up of the Land north of Turnock Street after the construction of Turnock Street in 1997 caused the vegetation to change so that a Wallum Froglet habitat was established when it had not otherwise existed prior to the construction of Turnock Street and the wetting up of the Land. 249The vegetation evidence is also relevant to the hydrology issue of whether the Land became wetter after the construction of Turnock Street in 1997. However it is unnecessary to analyse the vegetation evidence in relation to that issue because the hydrology experts agreed and I have already found, that the Land to the north of Turnock Street became wetter after the construction of Turnock Street. If there were species north of Turnock Street after 1997 that thrive in wet conditions that were not present prior to the construction of Turnock Street in 1997 there would be further justification for the conclusion that I have already reached that the Land became wetter after 1997. However, as I say, it is not necessary to analyse the evidence for that purpose. 250The plaintiff submitted that the wetting up of the Land north of Turnock Street caused the vegetation north of Turnock Street to become more suitable as frog habitat because of the increase in sedges and wet vegetation and the reduction in grasses and exotic species that had previously been prevalent. The plaintiff also submitted that there was a change in the abundance of the sedge type species to the north of Turnock Street that contributed to the establishment of suitable habitat for the Wallum Froglet because it supplied one of three essential characteristics identified for that habitat: (1) slightly acid soils; (2) Wallum vegetation, in this case sedge wetland vegetation; and (3) the presence close to that vegetation of ephemeral ponds. It was submitted that the hydrological cause, the wetting up of the Land, is the only probable explanation for the change in the vegetation because some species disappeared from the south of Turnock Street and other species became much more prevalent to the north of Turnock Street after 1997. 251The defendant submitted that prior to the construction of Turnock Street plant species typical of the Wallum Froglet habitat were dominant both north and south of Turnock Street and the construction of Turnock Street has not affected vegetation composition. The defendant also submitted that any emergence of vegetation north of Turnock Street suitable for Wallum Froglets is due to land management techniques such as slashing and not hydrological changes. 252The determination of this issue requires an assessment of the vegetation on the Land prior to and after the construction of Turnock Street. For convenience I will simply refer to the date 1997 in dealing with these comparisons. In expressing their opinions in relation to the nature of the vegetation on the Land prior to 1997, the experts relied in part on Mr Murray's 1992 vegetation survey referred to earlier in this judgment. In expressing their opinions on the vegetation on the Land after 1997 the experts relied in part on the survey conducted by Dr Smith and Mr GN Elks in 2007 (Elks G and Smith A (2007) Vegetation of Gales Holdings, West Kingscliff. Austeco Environmental Consultants). 253The vegetation experts agreed in their Joint Statement (Ex PD 2) that "vegetation communities on the low-lying generally tree less parts of the site were similar north and south of Turnock Street" prior to the 1997. All of the experts agreed in concurrent session that the surveys show that the species composition and vegetation communities on the Land prior to 1997 was different to the species composition and vegetation communities on the Land after 1997 (tr 699-701). 254Mr Murray expressed the opinion that elevated water tables and increased frequency and duration of high water events would cause the emergence of species such as sedges, for instance schoenoplectus mucronatus and lepironia articulata . He said that there is a suite of species that he would expect to see more prevalent on the Land if there were permanent levels of change to the water table. He accepted that those species are present in the "wetter parts" of the Land but said that they have not really taken over to the extent that he would expect (tr 713). 255Mr Murray analysed a 1995 aerial photo and observed tracks all over the Land and concluded that "every available piece" of the Land had been driven over. He also expressed the view that there is a whole range of species that are assisted in their growth by slashing. One of them is the exotic grasses that are on the Land and others such as rhizomatous grasses like the common reed, with underground roots so that when slashed they regrow easily and quickly. 256Dr Benwell expressed the view that slashing rather than the wetting up of the Land had changed the whole plant community. He said that if the vegetation had changed because of the wetting up of the Land he would expect to see different species that are characteristic of wetter soils and a higher water table. He said there was no sign of such species coming in but rather the vegetation had been cut back all the time by slashing and it was going into an early regrowth phase. He said it is basically the same plant community but just a different stage of growth (tr 714). Dr Benwell conceded that one species that would emerge because of the wetting up of the Land, sphagnum moss , was growing in the ruts on the Land north of Turnock Street (tr 715). However he expressed the view that any change in the species composition and vegetation communities is not due to the increase in the wetness of the Land north of Turnock Street (tr 715). 257Dr Clements said that the growth of sphagnum moss is a real indicator of how wet the soil is at the time of observation (tr 718). Her view was that the species composition and vegetation communities have changed because of the increase in the wetness of the Land. Dr Clements said that slashing has an effect on the "structure" of the species but the vegetation community remains the same and the species composition remains very similar (tr 721-722). 258It is accepted by the experts that blechnum fern was a dominant species at the time Mr Warren conducted his surveys in 1992 and 1996. It is also accepted that blechnum fern has always been on the Land. However Dr Clements observed that when there is an increase in moisture there is an increase in the occurrence of blechnum fern and it is more abundant where the soils are wetter. 259Dr Smith has walked over the Land since 2003 and said that he had observed that the vegetation north of Turnock Street had become characteristically wetter over time. He gave the following evidence (tr 724): Sphagnum moss is a very important indicator of a swamp wetland and it simply doesn't occur to the south, and it didn't previously occur to the north. So it's something that has accumulated slowly over time. And it also persists in areas that are slashed. So while I accept that there is a difference in the structure and appearance of vegetation of Turnock Street as you cross from the unslashed froglet area to the slashed grassland to the north, I took - intentionally took note of what was happening to the Sphagnum moss, and the Sphagnum moss was continuing to the north in the slashed areas. Because it's low growing, you wouldn't expect it to be affected by slashing. So I think that species, that single species alone, is sufficient evidence that the area to the north has become wetter, because you simply don't get that plant growing in conditions other than frequent high moisture level near the ground surface. 260The abundance of sphagnum moss is greater close to the northern side of Turnock Street than elsewhere. There is no abundance of sphagnum moss to the south of Turnock Street. The presence of the drains south of Turnock Street was identified as a factor for the absence of the sphagnum moss on that side of the street. 261It is understandable that the vegetation experts focused on whether the Land was wetter because that was an issue in the proceedings until the hydrology experts agreed that the Land was wetter. I have found that the Land became wetter because of the inadequacy in the drainage as outlined earlier. The issue for the vegetation experts is whether that wetness caused a change in the vegetation north of Turnock Street such that a Wallum Froglet habitat was established when, if the Land had not been wetter, it would not have been established. 262The following exchange in the concurrent session is of some significance (tr 731-732, 734, 743): HER HONOUR: No. I am asking you what species established or changed north as a result of the increased wetness, in your opinion. DR CLEMENTS: They increased in abundance north. They have always been hanging around, but they increase in abundance once you increase the water. HER HONOUR: There is nothing new? DR CLEMENTS: There is nothing totally new. They are in lower numbers south, but when you put more water on it, it becomes more favourable for these native wetland plants to grow. When you take the water away, the exotic pasture species are more successful. DR SMITH: Could I ask Dr Clements, does that include sphagnum moss, because, as far as I am aware, that is actually a new record north? DR CLEMENTS: It is a native wetland plant. That is a new record but it historically would have occurred, because we have - the soils are telling us historically. DR SMITH: Pre drain. DR CLEMENTS: Pre draining and pre clearing for agriculture. They probably occurred then. Then (sic) may have occurred in some flood event post the drains, when drains weren't working, or something similar, and you are just lucky when you pick it up. HER HONOUR: So, the species are the same. There is just more of them. DR CLEMENTS: Yes. MR MURRAY: ... I certainly agree with the fact that we have the same essential vegetation type .. ... HER HONOUR: Yes. I think everybody agrees there is no difference in the species or the vegetation on the north side of the land prior to 1997 and post 1997, except for the moss. Is that right? DR CLEMENTS: No, because pasture species do not grow under water. So, what I am seeing north of Turnock Street is a loss of the exotic pasture species; a massive decrease in the occurrence of those pasture species. The other thing I noticed-- HER HONOUR: Sorry, there is nothing new. DR CLEMENTS: In terms of species, no, there is nothing new. You just get a decrease in occurrence of pasture species north of Turnock Street because pasture species do not grow under water. HER HONOUR: ... The fact is, as I could find after this very helpful discussion, there was no change in species. Is that correct? DR SMITH: Apart from the moss. DR CLEMENTS: And the decrease. DR BENWELL : Changing the structure of the vegetation. ... HER HONOUR: So, I think the common factor is that the species haven't changed. DR BENWELL: Yeah, no, the species list for the site is the same, more or less. HER HONOUR: Whether they be slashed or not? DR BENWELL: Yes, yeah, I think if you did a survey right across the whole slashed area you will pick up all the species in some abundance or other. 263Notwithstanding that there is "nothing new", Dr Clements recorded distinct differences between the vegetation north and south of Turnock Street in January 2011. Dr Clements recorded the dominant species along a 300m transect which was parallel to Dr Webb's hydrology transect. Dr Clements explained that the presence of phragmites in relatively equal abundance north and south of Turnock Street is consistent with the water table being close to the surface even south of Turnock Street although it is higher north of Turnock Street. Similarly the predominance of paspalum urvillei south of Turnock Street is consistent with the water table being high but not "over the top" (tr 752). 264Dr Smith concluded that immediately prior to 1997 potential Wallum Froglet habitat to the north of where Turnock Street was located was limited to a small patch near the Pearl Street stormwater outlet and a small patch of wet heath near the current roundabout. However Dr Smith concluded that following construction of Turnock Street and Elrond Drive the whole of the area north of Turnock Street below about 1m AHD became potential Wallum Froglet breeding habitat. 265Dr Clements observed that the vegetation south of Turnock Street is dominated by exotic pasture species. She referred to the increased abundance of the pasture species south of Turnock Street, in particular setaria sphacelata and paspalum urvillei. Dr Clements said that these pasture species are consistent with the land being dry. The native species baumea rubiginosa and blechnum indicum were much more abundant north of Turnock Street than south of Turnock Street. Native species baloskion tetraphyllum, gahnia sieberiana, sphagnum moss and villarsia exaltata were also abundant north of Turnock Street but absent south of Turnock Street. 266The plaintiff argued that it is not correct to submit, as the defendant did, that the composition of vegetation in the area which is now the Wallum Froglet habitat is substantially the same as it was prior to the construction of Turnock Street. The plaintiff referred to Mr Murray's survey in 1992 in which he recorded wetland species blechnum indicum and gahnia sieberiana as among the dominant species in a polygon that covered the area in which the Wallum Froglet habitat now is. Mr Murray's 1992 survey used polygons created to describe the extent of the vegetation communities. These are approximately the same as the mapping done by Mr Warren in 1994. Mr Warren mapped most of the Land that is now froglet habitat as fernland/grassland in 1994 and identified a number of species as the main species in that community including blechnum indicum , gahnia sieberiana and baumea rubiginosa . Mr Warren did not attempt to measure the relevant abundance of the species listed in his report. Mr Elks and Dr Smith (2007) recorded baumea rubiginosa and hemarthia uncinate as amongst the dominant species in the area. 267None of the surveys done by Mr Murray (1992) or Mr Warren (1994) recorded the presence of the wetland species hemarthia uncinate or sphagnum moss that Dr Clements recorded in the habitat. Other wetland species identified by Dr Clements in the area included baloskion tetraphyllum, philydrum, phragmites and villarsia exaltata. Most of these were not identified by Mr Murray or Mr Warren. 268The plaintiff submitted that the only plausible explanation for the changes observed in species composition and vegetation community is the rise in the water table north of Turnock Street. It was submitted that this explanation is consistent with the appearance of sphagnum moss north of Turnock Street but not south of Turnock Street. 269The plaintiff submitted that the sphagnum moss is a very good indicator of the nature of the Land at particular times. It is accepted by the experts that sphagnum moss cannot survive when the Land is inundated with water. It was submitted that its presence is consistent with the decline of persistent wetness caused by better drainage conditions north of Turnock Street and that its presence and absence is almost perfectly consistent with the hydrological conditions described by Dr Webb. 270The defendant submitted that prior to 1997 species typical of the environment in which Wallum Froglets breed and feed were dominant north and south of Turnock Street. The plaintiff submitted that this contention overlooked the evidence of Dr Smith that there are three critical habitat requirements, referred to above, which must be present for Wallum Froglet habitat. The plaintiff submitted that the presence of Wallum vegetation (coastal heath and wetland vegetation), by itself, is not an indicium of suitable habitat for the Wallum Froglet. It was submitted that if that were the case the froglet would be widespread and secure, as is Wallum vegetation, rather than vulnerable to extinction. 271It is clear that the combination of species and the structure of the vegetation communities were such after 1997 that the Wallum Froglet habitat was created. There are probably four propositions in relation to this creation. The first is that there is nothing new in this habitat. The vegetation has always been the same and its creation could have occurred at any time irrespective of the construction of Turnock Street. The second is that even if the vegetation is the same, it was the wetting up of the Land that caused the abundance of the wetter species appropriate for the creation of the Wallum Froglet habitat. The third is that it was land management, slashing, that caused the creation of the habitat and not the wetting up of the Land. The fourth is that it was a combination of both the wetting up of the Land and the slashing that caused the creation of the habitat. 272The first proposition is not really sustainable. It is true that there is "nothing new" in the type of vegetation on the Land. The vegetation has always been there but in different composition and communities. There had to be particular circumstances for the creation of the habitat in the area that it now exists and it is probable that those circumstances did not exist before 1997. The Land is wetter and it is probable that such wetness was a contributing factor in the creation of the Wallum Froglet habitat. However it probably was not the only factor that contributed to the creation of the habitat. Certainly the flourishing of the sphagnum moss on the Land north of Turnock Street evidences the wetness of the Land. However that does not mean that the slashing of the Land was not a contributing factor to the creation of the habitat. 273Dr Benwell gave evidence that slashing on the Land had a big impact on the "floristic composition of the plant communities and their structure" (tr 707). His evidence included the following (tr 714-715): A. I see the slashing as it is changing the whole plant community. It is not just grasses it is sedge being favoured, herbs. So it is a whole range of native and exotic herbs, grasses, sedges, they are being favoured by this slashing and some of them are just being changed in abundance they are present in both the slashed and unslashed, but in different abundance. ... Q. I thought we established that they are pre 1997 and post there were different species composition. A. It is, yes, it is due to the serial, to the effect of slashing changing vegetation. Q. Coming back to what you said, I don't want any confusion about this, you earlier agreed that the pre 1997 surveys and post 1997 surveys establish that there are different species composition and vegetation communities, that's established on your opinion. A. Yes. Q. We have moved to the next step. You are telling me on the assumption that the northern land, that is north of Turnock Street, is wetter and I am trying to understand whether you say that the increase in moisture and wetness on the northern land has had an effect, that is it has caused a difference in species composition and vegetation, was it that that caused it? A. Yes, I was looking for evidence of changes and species composition which could be due to increased wetness and I just can't find any really obvious ones. Q. Any at all? A. One, perhaps one difference was the sphagnum moss growing in the ruts on the northern side of the site. But that could also be due to a soil nutrient gradient across the site. ... Q. So I understand your opinion to be that the change in the species composition and vegetation communities that have been observed is not due to the increase in wetness of the land north of Turnock Street? A. Yes. 274The plaintiff submitted that even Dr Benwell admitted that sphagnum moss could not be affected by slashing because it was a ground dweller and slashing only affects the species that sprout. Thus, it was submitted, the presence of sphagnum moss north of Turnock Street is contrary to Dr Benwell's hypothesis that slashing is controlling the abundances and presence and absence of species. It was conceded that there was no doubt that slashing affects the structural nature of plant communities by reducing the height of all but groundcovers and that it enables new growth. However the plaintiff submitted that it cannot be the "principal" cause of the changes in vegetation observed on the Land. This submission that it was not the principal cause accommodates the fourth proposition of a combination of causes including both wetness and slashing. It was not suggested that slashing, without wetness, could have caused the creation of the habitat. 275Dr Clements expressed the view that slashing alters vegetation height but not vegetation species. The roots remain in the soil so the same species will re-grow after slashing. This is consistent with the observations of Dr Clements along the vegetation transect that there were predominantly the same species in the slashed and unslashed areas north of Turnock Street. However it was noted that further north of Turnock Street the Land became drier and the wetland species became less abundant consistent with wetness being the main cause of vegetation change. Dr Clements noted in her evidence that gahnia sieberiana persists after slashing. Baumea rubiginosa is also unlikely to be affected by slashing and it is low lying and grows quickly. It is observed in both the slashed and unslashed areas. 276Dr Smith compared the vegetation in the two areas north and south of Turnock Street where the plaintiff was not permitted to slash under the conditions of the development consent. Those areas had not been slashed for three years. It was submitted that if Dr Benwell is correct that it is slashing and not wetness that drives species composition and abundance, then the area to the south of Turnock Street, which is left unslashed, should have the same characteristics of the area to the north of Turnock Street. Before Turnock Street was constructed they were part of the same vegetation community. However the unslashed area south of Turnock Street does not have the same vegetation characteristics as the area north of Turnock Street. There is no sphagnum moss in it and there is a far greater abundance of sedge in the north than the south. Thus, it was submitted it is the wetness and not the slashing that drives the changes in vegetation observed north of Turnock Street. 277I am satisfied that it is probable that the wetting up of the Land was the dominant factor in the creation of the Wallum Froglet habitat. However I am also satisfied that the slashing of the Land was a factor in the creation of the habitat. Ecology (Frogs) Issues 278Three experts assisted the Court in these issues: Dr Smith (who also gave evidence in the vegetation concurrent session and whose background is referred to earlier), Dr Michael Mahony and Mr Peter Parker. 279Dr Michael Mahony is an ecologist and conservation biologist with over thirty years experience, with particular expertise in the ecology and biology of Australian frogs. He is the head of Environmental Science and Management at the University of Newcastle. Dr Mahony holds a Bachelor of Arts and a Doctor of Philosophy from Macquarie University. 280Mr Peter Parker is an ecologist and environmental consultant. He has over thirty-five years experience in conducting flora and fauna surveys and thirty years experience in surveying the distribution and habitats of threatened species in northern New South Wales. He is the principal of Peter Parker Environmental Consultants Pty Ltd and holds a Master of Philosophy Research Degree from Griffith University. 281Dr Smith provided the reports already referred to above and he was a party to the Joint Report of the Ecologists dated 14 February 2011 (Ex PD1). Dr Mahoney provided a report dated 1 September 2010 and was a party to the Joint Report of 14 February 2011. Mr Parker provided a report dated 6 December 2010 and was a party to the Joint Report dated 14 February 2011. These experts gave evidence in concurrent session on 14 March 2011. 282The experts agreed that Wallum Froglets require ephemeral ponds that last long enough for completion of embryonic and larval (tadpole) life stage for successful breeding. This may range from about 32 or 34 days to 6 months. Mr Parker considered a minimum of 32 days is sufficient. Dr Mahoney preferred a minimum of 34 days. Wallum Froglets can tolerate acidic water conditions more so than other non-acidic adapted frog species. The Joint Report included the following: 3. Wallum Froglet terrestrial habitat consists of a broad range of native and occasionally partially exotic vegetation types that occur within a limited distance of breeding sites. Studies by Pyke and White (unpublished) have indicated a mean movement distance from breeding sites of 18 metres and a maximum of 84 m on dry nights, and a mean of 4 m and maximum of 15 m on wet nights. 4. Dispersing froglets may move far greater distances than the maximum of 84 m reported above. 5. Wallum Froglets can colonise and breed in created habitat. 6. ...There were no significant barriers to frog movement prior to the construction of Turnock street and Elrond Drive in 1997 and the wallum froglet could readily migrate over quite a large and suitable habitat. Thus the subject land north of Turnock Street would have comprised only a part of the Wallum Froglet habitat at west Kingscliff in which the 'local population' occurred. ... 9. ...An increase in ground water level (surface water ponding) of 10 to 20 centimetres can result in the creation of new Wallum Froglet habitat in areas where it previously did not occur. 283There is no issue that the number of Wallum Froglets on the Land increased between 1999 and 2003. In July 1998 Mr Warren identified a single Wallum Froglet call. This was the first time that the Wallum Froglet was identified on the Land, notwithstanding a number of earlier surveys. Mr Parker claimed that he heard "1000 calls" of Wallum Froglets on the Land in 2003. However the defendant contended that the Wallum Froglet was present on the Land prior to the construction of Turnock Street. It was submitted that the more likely explanation of the presence of a population of Wallum Froglets of the extent encountered by Mr Parker, described by the defendant as an "explosion", is that the earlier surveys did not accurately reflect the situation. 284Mr Parker's evidence in relation to the document in which he recorded the 1000 calls included the following (tr 887-888): The diagram I produced in 2003 was produced for council plans and I did pretty little pictures and tried to make it as simple as I could and it's turned out to be way too complicated and ambiguous, I agree. Dr Mahoney correctly interpreted that one frog picture doesn't equal a thousand. We estimated, myself and Dr White about a thousand frogs over the whole of the site. We walked throughout the site. ... I tried to in this diagram, poorly explained I accept, cluster the frogs. The closer the frog together is the better quality frog habitats so as you move off to the north west of the site north of the site the froglet habitat is of poorer quality. 285Dr Mahoney expressed the opinion that the land north of Turnock Street did not contain habitat for the Wallum Froglet prior to 1997. In support of this opinion Dr Mahoney referred to Mr Warren's two surveys in the early 1990s and the Woodward-Clyde report of 1996. He noted that none of those surveys observed the Froglet which is easy to detect with its strong and strident call. He emphasised that the Woodward-Clyde survey included several methods appropriate for detecting the Froglet in its terrestrial and aquatic habitats (pit-line traps, call recordings) and was conducted in the appropriate location and time to record the Froglet. The Froglet was first observed in July 1998 south of Turnock Street and subsequently north of Turnock Street as reported by Mr Warren in 1999. 286Dr Mahoney observed that Wallum Froglets are capable of moving over roads and embankments and expressed the opinion that with the wetting up of the Land north of Turnock Street ephemeral ponding occurred suitable for breeding, foraging and sheltering of the Froglet and its population expanded under those conditions. He concluded that it was unlikely that a population of Wallum Froglets occurred on the Land prior to 1999. It was most likely that the population occurred in the Paperbark swamp forest with a fern/grass sedge understorey in the lower topographic areas in the south west of the Land in Lots 26C and 26D. His opinion was as follows: Following the construction of Turnock Street in 1997 and with other developments in the local area, considerable changes occurred in the hydrology of the area to the north of Turnock Street. After that time froglets colonised the wetlands habitats that formed to the north of Turnock Street. Initially the population was small and limited in distribution to the low topographic area which now surrounds the roundabout on Turnock Street. With an increase in the extent of the surface water which provided habitat for the froglet, the population grew and was more widely distributed to the north of Turnock Street. This was manifest by the occurrence of ponding of water across a larger portion of the land and a consequent increase in the habitat available to the wallum froglet, which in turn increased its population size and distribution to the north of Turnock Street. 287Dr Mahoney was of the view that the origin of the Wallum Froglet that colonised to the north of Turnock Street was most likely to be from the lower lying Paperbark swamp forest areas to the southwest of the Land on Lots 26C and 26D. He noted that after the construction of the table drain in 2004 the extent of surface ponding and the length of ponding decreased and the Wallum Froglet numbers decreased. He emphasised this point in support of his conclusion that without the wetting up of the Land to the north of Turnock Street there would not have been a local viable population of the Wallum Froglet to the north of Turnock Street. 288The recording of the call of the Wallum Froglet (Ex OO) supports Dr Mahoney's claim that it is a distinctive call. Notwithstanding this, the defendant persisted in its submission that the surveys conducted prior to 1999 failed to identify the presence of the Wallum Froglet even though it was likely to have been present on the Land at the time. That submission is based on the so-called "explosion" in numbers of froglets identified by Mr Parker in 2003. The defendant submitted that the increase in numbers was somewhat of a "mystery" (tr 1282). It was submitted that there was no scientific explanation for the increase in numbers between 2002 when a few froglets were identified to a thousand froglets in 2003. Mr Parker's estimate of a thousand calls was reached when he stood on the side of the Land and estimated numbers from a distance of up to 150 metres. Dr Mahoney criticised Mr Parker's 2003 observations noting the absence of any quantitative methodology as to how he distinguished 1000 individual calls. However Dr Mahoney's report included the following (par 314): The most pertinent observation is the large increase in the distribution and abundance of the Wallum froglet on the Subject Land in the period between surveys in 2001 and 2002 when Planit (2002) recorded a small number of froglets calling adjacent to the roundabout on Lot 11 to the situation reported Parker (2003) and White (2003). Planit (2003) ... also reported the abundance of Wallum froglets to the north of Turnock Street during autumn of 2003 and estimated a maximum of 275 calls/ha, which is not all that less than the estimate of >1000 individuals for the whole area reported by Parker (2003). 289On this analysis there was not the so-called "explosion" referred to by the defendant. In any event the increased number of froglets in 2003 is consistent with the biology and ecology of the froglets, which move widely and can rapidly colonise a suitable area. 290The defendant criticised the earlier surveys as containing opportunistic sightings and calls and highlighted the fact that: Mr Warren's survey in 1994 was not a fauna survey; Woodward-Clyde's 1996 survey was of flora and fauna at five spot locations in a narrow road corridor for Turnock Street's construction and in an unusually dry month; and Mr Warren's survey in July 1998 when a single call was detected in Lot 26C or 26D was carried out in a relatively dry month. The defendant submitted that Dr Mahoney and Dr Smith based their opinions on the unlikelihood of Mr Warren not hearing the froglet if it had been present. Dr Mahoney gave the following evidence in the concurrent session in relation to the increase in the number of froglets in 2003 (tr 885): A No, I think it is explicable if you have a period of long rainfall, of rainfall and ignoring whether it's because of blockage and drains, the photos I have seen certainly indicate that the surface water, the extent of surface water was considerable and in those conditions the Wallum Froglet would disperse and rapidly take up that habitat. The alternative to think about is that when the whole thing is flooded like a swimming pool and there are photographs that show that for 2003, none of the - a terrestrial frog is essentially wiped out in that situation, there is no more terrestrial habitat for the bottom half of the north of Turnock Street. So they have to reinvade at the end of that major flood. So if, in the beginning of 2003 we have this massive rain event at the end of summer, they have flooded the site, the Wallum Froglet had to have actually been wiped out on the site because it was essentially a swimming pool. So the fact that they then move back as it became ephemeral at the end of that wetting, is an indication of their capacity to disperse. Q. So your explanation then is that the froglets that Mr Parker observed are likely to be froglets that hadn't bred north of Turnock Street, but returned to the north of Turnock Street after the Turnock Street population had been wiped out? A. Or they may have moved to the higher ground to the east on the dune, but they have to reinvade from somewhere or colonise it from somewhere, because they are not aquatic in the sense they don't live underneath the water. So I mean, yeah, I think that you add those two things together and in a short period of time, the animal can quickly colonise the suitable smaller wetland habitats once the flood is over. 291The defendant submitted that this thesis propounded by Dr Mahoney is important because it demonstrates that the Froglets may have bred south of Turnock Street and taken the opportunity to establish themselves north of Turnock Street at a time when attractive conditions presented themselves after the flooding. It was submitted that this adds weight to Mr Parker's views that Wallum Froglets are likely to have inhabited the Land on earlier occasions and suggests the absence of any clear link between the construction of Turnock Street and the emergence of a Froglet population. 292The plaintiff submitted that prior to the construction of Turnock Street, Wallum Froglets were not detected in the area which is now north of Turnock Street. There is no doubt that the Froglet call is distinctive and by 1994 Mr Warren was familiar with its call. It was submitted that the survey methods used by Mr Warren in 1996 required field workers to be on site for some time and Dr Mahoney's evidence was that if Wallum Froglets were present on the Land at that time they would have been detected (tr 845). It was submitted that the most likely reason why Mr Warren did not detect Wallum Froglets or report semi-permanent ephemeral ponding was because at that time the Land drained freely and surface and groundwater were not impeded. The plaintiff submitted that the essential element to the Wallum Froglet habitat (even if the appropriate vegetation was present), ephemeral ponding for the requisite period, was not present. It was submitted that the surveys conducted prior to 1997 should be accepted as accurate and leading to the conclusion that the Wallum Froglet was not present on the Land north of Turnock Street until after the construction of Turnock Street. 293I am not satisfied that I should reject the surveys prior to 1997 as inaccurate. I accept that some of the surveys were conducted for reasons other than identifying the Wallum Froglet. However I am satisfied that the Wallum Froglet was probably not present on the Land north of Turnock Street until after the construction of Turnock Street. I am also satisfied that the hydrology conditions, prior to the construction of the table drains in 2004, were such that ephemeral ponding occurred enabling the Wallum Froglet to take hold some time after 1999. The plaintiff's Opening Submissions included a contention that there was a "great abundance" of the Wallum Froglets "certainly from 2003 and possibly earlier" (par 9). This great abundance" was recorded in April 2003. I am satisfied that a viable population of Wallum Froglets was established on the Land north of Turnock Street probably in late 2002/early 2003. Conclusions from Expert Assistance 294It is appropriate to set out my findings in relation to each of the issues in the plaintiff's claims that I have made with the assistance of the expert evidence. They are as follows: (1) There was no adequate alternative drainage route to replace the Northern Drain after it was filled by the developer of NPE; (2) the 1200 mm pipe was inadequate for the proper drainage of the Land in all the circumstances; (3) the single culvert under Elrond Drive was not adequate for the proper drainage of the Land; (4) the construction of Turnock Street with no culverts at ground level was not adequate for the proper drainage of the Land and/or was an impediment to the proper drainage of the Land; (5) the inadequate drainage combined with the increase in stormwater run-off caused the wetting up of the Land after the construction of Turnock Street; (6) the wetting up of the Land and to a lesser extent the slashing of the Land caused the vegetation north of Turnock Street to change so that the species composition and vegetation community was suitable for Wallum Froglets; (7) the wetting up of the Land after the construction of Turnock Street caused ephemeral ponding, enabling the Wallum Froglets to take hold in the Wallum Froglet habitat north of Turnock Street in late 2002/early 2003; and (8) the velocity of the stormwater coming onto the Land in the Quigan Street vicinity has increased because of a failure in the Quigan Street stormwater outlets. Applicable Principles 295Nuisance is the unreasonable interference with the use and enjoyment of a person's land: Hargrave v Goldman (1963) 110 CLR 40 at 62 per Windeyer J; Sedleigh-Denfield v O'Callaghan & Ors [1940] AC 880 at 904 per Lord Wright. The determination of whether there has been "unreasonable interference" is by the application of an objective test - whether a person of ordinary habits and sensibilities in the plaintiff's position and circumstance would regard the interference with the enjoyment of the land as unreasonable. It is necessary to decide whether there has been "an inconvenience materially interfering with the ordinary comfort physically of human existence, not merely according to elegant or dainty modes and habits of living, but according to plain and sober and simple notions" of the community: Walter v Selfe (1851) 4 De G. & Sm. 315 at 322, cited with approval by Jordan CJ in Don Brass Foundry Pty Ltd v Stead (1948) 48 SR (NSW) 482 at 486. These include the notion of "reasonable give and take": Bamford v Turnley (1862) 3 B.& S. 66 at 83-4 cited with approval by Jordan CJ in Don Brass Foundry Pty Ltd v Stead at 487. 296Liability in nuisance is not strict or absolute and fault in the alleged wrongdoer must be shown: Sutherland Shire Council v Becker (2006) 150 LGERA 184; [2006] NSWCA 344 at 225-226 [118]-[119] per Bryson JA. Damages may be awarded for reasonably foreseeable harm caused by the defendant's activity that amounted to the nuisance: Overseas Tankship (UK) Limited v Miller Steamship Company Pty Ltd ("Wagon Mound (No 2)") [1967] 1 AC 617 at 639-640 per Lord Reid. The Court may also grant an injunction, including a permanent injunction, to restrain an ongoing nuisance: Pride of Derby and Derbyshire Angling Association Ltd v British Celanese Ltd [1953] 1 Ch 149 at 181 per Evershed MR; 194 per Romer LJ. 297In Willoughby Municipal Council v Halstead (1916) 22 CLR 352 the local Council in the exercise of its statutory powers, laid an 18 inch pipe through Mrs Halstead's (the plaintiff's) land to carry off water flowing from the north. This was in execution of a statutory power conferred on the Council. The plaintiff alleged that by reason of the insufficient size and faulty construction of the pipe it did not carry off heavy rainfall with the consequence that large quantities of water accumulated on her land and became stagnant and offensive. Griffith CJ (at 356) observed that when the defendants brought water through the pipe onto the plaintiff's land "they were bound to make provision by an adequate drain for carrying it further, and the adequacy of such a drain would not depend upon the original but upon the then existing condition of the surface". Isaacs and Rich JJ said at 360: The quantity and concentration of filth-impregnated storm water on the plaintiff's land was manifestly greater than would have been the case had the Council been altogether inactive in relation to the drain. 298A number of judgments in nuisance cases have referred to the expression used in Clerk & Lindsell on Torts 19 th ed. (Sweet & Maxwell, London 2006), [20-39] p 1185, that in a particular type of nuisance (where the defendant creates (rather than adopts or continues) a nuisance and knew, or ought to have known, that as a consequence of its actions harm to its neighbour was reasonably foreseeable) "nuisance and negligence coincide": Robson v Leischke (2008) 72 NSWLR 98 at 109-110 [47]-[48]; Quick v Alpine Nurseries Sales Pty Ltd [2010] NSWSC 1248 at [142], [147]. This coincidence has created some complexity, however the "duty" that is imposed in that circumstance is an obligation to take the positive action a reasonable person in that position and circumstance would take, to eliminate the foreseeable risk of damage from the nuisance: Sedleigh-Denfield at 894, 905; Wagon Mound (No 2) at 639; see also Owners Strata Plan 4085 v Mallone (2006) 12 BPR 23,691 at 23,693 [22] 299Certain public bodies, including local councils, have a limited immunity from liability for a nuisance arising from an exercise of their statutory powers. As Gleeson CJ, Gummow, Hayne and Callinan JJ said in Bankstown City Council v Alamdo Holdings Pty Ltd (2005) 223 CLR 660; [2005] HCA 46 at [16], "a body such as the Council is not, without negligence on its part, liable for a nuisance attributable to the exercise of, or failure to exercise, its statutory powers". The expression "negligence" is here used in a "special sense", requiring "the undertaker, as a condition of obtaining immunity from action, to carry out the work and conduct the operation with all reasonable regard, and care for the interests of other persons": Melaleuca Estate Pty Ltd v Port Stephens Council (2006) 143 LGERA 319; [2006] NSWCA 31 at 332-333 [47]-[48] per Giles JA, referring to Allen v Gulf Oil Refining Ltd [1981] AC 1001 per Lord Wilberforce. As Giles JA said in Melaleuca Estate at 333 [49], "if exercise of [the defendant's] statutory power means that the interests of other persons are harmed despite all reasonable regard and care for those interests, there is no right of action" against the defendant. Negligence in this "special sense" is to be applied in only limited circumstances. It is to be applied in the special circumstance where the inevitable consequence of the actions of the statutory authority will be harm to others. If the statutory authority does not act with such regard it cannot claim the immunity. Negligence otherwise than in this special circumstance of nuisance means that there is a failure to take reasonable steps to eliminate the foreseeable risk of damage from the nuisance. 300Consistently with the notion of give and take, a neighbour may tolerate an interference with the enjoyment of the land for various reasons including perhaps a need to engender a friendly neighbourly relationship. That tolerance, an indicium of which is a lack of complaint, may be taken into account as evidence of there being no "unreasonable" interference with the enjoyment of the land. However when the interference has reached the stage that the neighbour no longer feels obliged or willing to tolerate it, either because of the continuance of it or the more serious nature of it, depending upon the particular circumstances of the case, the neighbour will be entitled to claim that there is an unreasonable interference with the enjoyment of the land, notwithstanding that earlier tolerance. However the neighbour will not be entitled to claim damages for the interference that was tolerated prior to the complaint being made, or put another way, in respect of which there was acquiescence: Duke of Leeds v Earl of Amhurst (1846) 2 Ph 117 at 124; Orr v Ford (1989) 167 CLR 316 at 341 per Deane J. Where there is a change in approach in the neighbour who has hitherto acquiesced in the violation of the right of enjoyment of the land, it is necessary to inform the offender that tolerance has ceased. Characterisation of the plaintiff's claim 301There is a fundamental difference between the plaintiff and the defendant in relation to the nature of the nuisance claimed by the plaintiff. The plaintiff claims that it is the inundation of untreated stormwater runoff on the Land that has caused the unreasonable interference with the enjoyment of its Land. The defendant contends that properly understood, the plaintiff's claim is that it is the presence of the Wallum Froglets that is the nuisance, rather than the presence of the stormwater runoff on the Land. 302The defendant submitted that, contrary to the position propounded by the plaintiff, its claim is confined to loss of value of the development arising from the presence of the Wallum Froglet on the Land and not a complaint of damage to property. There is no doubt that in the early stages of the trial there was some blurring of the boundaries of the plaintiff's case. The plaintiff's Outline of Opening Submissions included the claim that the case "is about the loss of development rights and prospects" (par 4). Once the plaintiff abandoned its claim in negligence it focused on the elements of the nuisance case. 303The defendant submitted that in order to establish an entitlement to relief based in nuisance, the plaintiff must show that some other right has been infringed that the law of nuisance protects. The defendant relied upon two examples. The first related to the clear limitations in the categories of "rights" protected by the law of nuisance. In this regard it was conceded there could be no argument with the proposition that collapsing buildings are a substantial interference with a use and enjoyment of land, but relief in connection with such losses of that kind has not been available as a matter of course: Sutherland Shire Council v Becker at 189 [5] per Giles JA. The other example was in relation to what was described as the "rights of privacy". It was submitted that while the capacity of the plaintiff to exploit its property through the operation of commercial enterprise was clearly interfered with in Victoria Park Racing and Recreation Grounds Co Ltd v Taylor (1937) 58 CLR 479, the activities on neighbouring land which caused that interference were not recognised as a nuisance. Relief was denied because there was no damage to the plaintiff's property and there was no right incidental to its ownership of the property that was violated. 304The defendant submitted that it is necessary to determine whether there exists a right to which legal protection will extend which has been infringed. It was contended that the right the plaintiff alleges is, in substance, the right of a landowner to be free of wildlife the survival of which the law has seen fit to endeavour to promote and protect, and the presence of which is otherwise entirely innocuous. The defendant submitted that there is no such right, or alternatively no such entitlement, within the recognised scope of protection afforded by the law of nuisance. It was submitted that if the law does not recognise as a right, or as a benefit attaching to the ownership of property, the entitlement to be free of protected species, then that is the end of the matter. It was submitted it is not open to the Court to extend the scope of nuisance principles to protect rights that the law does not recognise. Alternatively it was submitted that if such an entitlement exists the plaintiff must overcome the obstacle of establishing that the right should be recognised as attracting protection under the law of nuisance. It was submitted that this would involve persuading the Court to expand the recognised categories of rights attracting protection. 305The defendant also submitted that in determining this aspect of the case an important consideration is to ensure that coherence with other legal principles and statutory schemes is preserved: Sutherland Shire Council v Becker at 189-190 [8]; Sullivan v Moody (2001) 207 CLR 562 at 580 [50]; Hill v Van Erp (1997) 188 CLR 159 at 231. It submitted that there is plainly incoherence between the existence of a legislative framework for the preservation of threatened species and the existence of a right, protected by the law of nuisance, to be free of the presence of protected species on one's land. The Threatened Species Conservation Act 1995 provides that upon listing of a species as vulnerable or endangered, persons may be liable for offences under that Act in relation to that species. Orders can be made restraining breaches or apprehended breaches of the Act and of acts harming a protected species. It was submitted that as nuisance protects private interests in the use and enjoyment of land, it would be anomalous for the law to recognise legislative limits upon such interests on the one hand and, on the other hand, to recognise remedies protecting such private interests enforceable by injunction or damages. 306It was suggested that a further example of incoherence is found in the circumstances that have given rise to the complaint in these proceedings, in that an invasion of Wallum Froglets from the area south of Turnock Street (apparently Lots 26C and 26D of the Land) was a realistic possibility (tr 848-851). It was submitted that if those Lots were under different ownership, that owner could not be restrained from preserving a Froglet habitat or be sued in damages if it preserves such a habitat and its Froglets invaded the Land. Accordingly it was submitted that if a neighbour cannot be made liable for protecting the Wallum Froglet and thereby exposing the plaintiff to the risk of invasion by protected fauna, then coherence requires that the defendant should not be exposed to such a liability. 307By way of further example the defendant submitted that if the Statement of Environmental Effects accompanying the NPE development had identified a community of Wallum Froglets on that site, adjacent to the Land, the question would arise as to how the defendant could perform its obligations to protect that population without exposing the plaintiff to the risk of froglet invasion and potential development restrictions. It was submitted that to extend the law of nuisance to provide protection of a right to be preserved from endangered species would impose an intolerable burden on the defendant in this case because of the possible twenty-seven different species potentially affected by development in the area. It was submitted that the defendant could not sensibly be burdened with the responsibility of ensuring that the habitat for each such endangered species will not be enhanced by development (for example, by providing cleaner water or more open space or trees in the vicinity of neighbouring lands) not least because the defendant is obliged to provide the creation of suitable habitat, not prevent it. 308The plaintiff submitted that the defendant's arguments about incoherence are based on an incorrect analysis of its claim that the existence of the Wallum Froglets is the harm rather than a consequence of the harm for which it seeks damages. The plaintiff submitted that its case is analogous to Cattanach v Melchior (2003) 215 CLR 1 in which the plaintiff was awarded damages for the birth of an unintended child resulting from a doctor's negligent advice and failure to warn. In Cattanach the High Court considered the existence of obligations imposed by the law to maintain and raise a child, including sanctions of the criminal law for a failure to maintain and support children. However the imposition of those legal obligations did not absolve the respondents from liability for damages: per McHugh and Gummow JJ at [59]; Callinan J at [295], [301]. It was submitted that in the present case, as in Cattanach , an award of damages of the kind sought by the plaintiff is consistent with the underlying notion that the availability of damages serves as a measure of deterrence of the defendant's tortious conduct. 309I am not sure that reliance on Cattanach supports the plaintiff's position. In any event, as I said above, the plaintiff submitted that the existence of the Wallum Froglet is not the "harm" alleged and any award of damages of the kind sought does not involve an extension of the law of nuisance. The plaintiff submitted that it relies on a long established category of the tort of nuisance arising from the discharge and retention of stormwater on land. It was submitted that it is this category of traditional nuisance referred to in Willoughby Municipal Council v Halstead that is relied upon rather than any notion of extending the law to include a right to be protected from threatened species. The right for which the plaintiff claims it is entitled to protection is its right to the enjoyment of the Land. It claims that the Land was inundated with untreated stormwater so that it could not enjoy it, a consequence of which was the establishment of the Wallum Froglet habitat that would otherwise not have been established because the Land would have been free of the water and the consequence of ephemeral ponding. 310The plaintiff submitted that the nuisance alleged by it arose not from an isolated act by the defendant but from a series of steps taken by it including: constructing or permitting the construction of stormwater outlets directing and concentrating stormwater runoff on the Land; permitting the filling of the Northern Drain without replacing it with an overland flow path for the Q100 storm; only requiring a drain to be sized for Q5 flows, but approving a drain which was undersized for the Q5 flows and also ineffectual; designing and constructing Turnock Street and Elrond Drive so that all but one of the culverts draining stormwater from the Land were placed above ground level; failing to provide a table drain to drain stormwater dammed by Turnock Street to a lawful point of discharge; and designing and constructing a culvert under Elrond Drive which was undersized for both the Q100 and the Q5 storm events. 311The plaintiff submitted that the harm caused by the discharges was worsened by the impaired drainage system, progressively established by or with the approval of the defendant. It was submitted that the defendant did so with knowledge of the incapacity and the deficiencies of that drainage system and therefore with "fault": Torette House Pty Ltd v Berkman (1940) 62 CLR 637 at 659. 312The plaintiff's claim is that the defendant's conduct has caused an increase in stormwater runoff on its Land that has caused an unreasonable interference with the enjoyment of its Land, irrespective of the presence of the Wallum Froglets. I accept that this is an accurate characterisation of the plaintiff's claim and I intend to consider whether there is an actionable nuisance on that basis. 313The plaintiff does contend that its measure of damages should include at least the cost of maintaining the Wallum Froglet habitat and the diminution in the value of its Land as developed, because the natural and foreseeable consequence of the inundation of the Land, the wetting up of the Land, was the establishment of the Wallum Froglet habitat. In these circumstances I will deal with the plaintiff's claim in two parts: first, the claim of unreasonable interference with the enjoyment of the Land irrespective of the presence of the Wallum Froglets; and secondly, its entitlement to recover damages for, inter alia : (a) the cost of establishing and maintaining the Wallum Froglet habitat; and (b) the loss of the use of that part of the Land for development. An unreasonable interference 314The relationship between these parties over the last 30 years is not free from complexity. It was in many respects very co-operative with the plaintiff being willing to provide and in fact providing funds to assist the defendant to complete various studies not only in respect of the drainage of the Land but also in respect of the drainage of the Kingscliff area generally. However they had a number of court cases when disagreement occurred in respect of particular aspects of their respective approaches to the development of the Land and/or the area generally. Their relationship appears to have deteriorated after the plaintiff published the political pamphlets criticising an officer of the defendant and the defendant generally. Notwithstanding this lengthy relationship in which the parties were communicating with each other on a regular basis there is no written communication in evidence between them prior to 2004 in which the plaintiff made a complaint that the enjoyment of its Land had been unreasonably interfered with by the presence of the stormwater run-off on the Land. The letter of 31 July 1974 suggested that the defendant should take responsibility for the "severe localised drainage problems" but made no claim of unreasonable interference with the enjoyment of the Land. 315However on 5 March 2003 the plaintiff's consultant Mr Glazebrook advised the defendant that the plaintiff was "no longer prepared to permit the unlawful discharge of concentrated stormwater flows" onto its Land. There was no reference in that letter to any unreasonable interference with the plaintiff's enjoyment of its Land. That letter was written in circumstances where the plaintiff was having difficulty obtaining development consent to fill the Land and to construct the proposed shopping centre. The terms of this letter suggest that prior to 5 March 2003, there was alleged unlawful discharge of concentrated stormwater flows onto the Land but that, for whatever reason, the plaintiff was prepared to permit it. However that permit was withdrawn as and from 5 March 2003. 316It is apparent that the plaintiff's priorities in respect of the Land over the years up to 5 March 2003 accommodated the stormwater on its Land without complaint. Dr Segal's evidence was that from as early as 1977 the plaintiff's plan has been to develop the Land into a combination of residential and retail uses. There is no issue between the parties that prior to any development of the Land it will be necessary to fill the Land. Accordingly the day-to-day use of the Land, initially with the grazing of cattle and later with the agistment of horses, were temporary uses until the Land was developed. However the plaintiff either directly or through its expert representatives took part in many, many meetings and at its own cost, retained numerous and various consultants to assist it, and at times to assist the defendant, in achieving some sensible and consensual regime and plan for the drainage of the Land and the area generally. I am satisfied that the plaintiff's attitude was that it would tolerate the presence of the stormwater run-off on its Land whilst these discussions and meetings were pursued for the joint endeavour (as it saw it at the time) of achieving a sensible and workable plan for the drainage of the Land and the area generally. However it was not prepared to tolerate it after 5 March 2003. 317On 4 May 2004, for the first time in this long relationship between these parties, the plaintiff claimed that the defendant's conduct in constructing Turnock Street with the consequential increased wetness of the Land, constituted an unreasonable interference with the enjoyment of its Land. 318The volume of water on the Land since 5 March 2003 has not only been described in evidence by the experts but photographs of the Land have been taken (Volume 6 of the Court Book) and have also been the subject of detailed observations by Dr Webb. The photographs are in various "series" - the "EDC series" being the Elrond Drive series of which there are 13 photographs taken during the period July 2003 and June 2008; the "TD series", being the Table Drain series, of which there are 16 photographs taken during the period July 2003 and March 2008; the "SW 1200 series", being the 1200mm Pipe series, of which there are 14 photographs taken during the period July 2003 and June 2008; the "NTS-E series", being the Land North of Turnock Street at Eastern Limit series, of which there are 69 photographs taken during the period March 2003 and March 2008; the "NTS-W series" being the Land North of Turnock Street at the Western Limit series, of which there are 29 photographs taken during the period March 2003 and June 2008; and a series of 28 photographs taken on 17 November 2004, 30 June 2005 and 16 April 2009 depicting drainage problems on Lots 26C and 26D, which was divided into three sets: the southern section of the Chinderah Drain adjoining Lot 26C ("DR-CHIND"); the south westerly drain within Lots 26C and 26D ("DR-SW"); and the cleared areas of Lots 26C and 26D north of the south westerly drain ("Lots 26C&D"). 319These photographs depict what may reasonably be described as inundation of parts of the Land between 2003 and 2008 through which it would be impossible to walk comfortably (or at all) because of the presence of the water as depicted - see especially photographs in the EDC series, in particular photographs 11 to 13; the SW 1200 series, in particular photographs 8 to 10, 13 and 14; the NTS-E series, in particular photographs 1 to 36, 49 to 52 and 62 to 66; and the NTS-W series, in particular photographs 3 to 8, 11 to 14, 18 to 22, 28 and 29. 320The plaintiff alleged that the stormwater coming onto the Land contained pollutants. The untreated stormwater from the defendant's drains is of different quality to the rainwater that falls directly onto the Land during storm events. It was not in serious issue that the stormwater from the drains would come from various sources including the roofs and downpipes of the buildings in the surrounding catchment. That stormwater consequently carried with it "such impurities as are ordinarily found in surface water so collected": Willoughby Municipal Council v Halstead at 357 per Griffith CJ. It would also come from areas in the catchment that are under development. In this regard the plaintiff relied upon the defendant's policy documents to claim that it is accepted that urban development increases "pollutant loads" in the stormwater runoff that is not treated (Ex UU: 5.5, page 29). The defendant's Development Design Specification for new developments requires the removal of pollutants from stormwater (Ex FF: D7 4-5). 321Baseline water quality data was collected by Dr Webb over the period December 2007 to November 2009 at four locations within the designated Wallum Froglet habitat and at three stormwater outlets that drain from the surrounding urban areas. Water samples were collected on 29 occasions during the two year monitoring period however not all locations were sampled on every occasion. 322The results showed that the observed conditions differ significantly from the water quality requirements imposed in the conditions to the 2008 Development Consent. In particular, the mean observed value of the water within the Wallum Froglet habitat is significantly above the requirements imposed by the development consent conditions for all parameters except turbidity and pH. Dr Perrens' report of 2 September 2010 (that was in evidence and was unchallenged) concluded that the two year monitoring program provided a good characterisation of the local water quality and provided sufficient data from which to derive a range of desirable and practicable water quality goals. It is true, as the defendant submitted, that the monitoring of the water quality was for the purpose of the accommodation of the Wallum Froglet habitat. Its submission that it did not provide proper evidence of pollutants in the stormwater is however rejected. 323The plaintiff claimed that the principal pollutants are suspended solids. It also submitted that there is no doubt that the urban stormwater is itself a pollutant and all of the defendant's policy documents treat it as such: (Ex EE; Ex FF; and Ex UU). The defendant submitted that the evidence relating to pollutants is confined to two areas: a single observation in general terms from Dr Webb regarding presence on the site of gross pollutants, in the form of plastic bottles and the like, immediately downstream of the Pearl Street outlet; and observations made in the HMC Environmental Consulting Pty Ltd report annexed to Dr Webb's August 2010 report. It was submitted that the evidence of gross pollutants does not establish an unreasonable interference amounting to nuisance. It is common ground that the Pearl Street catchment drains naturally to the Land. Stormwater flowing naturally onto the Land would be expected to carry gross pollutants of the type complained of whether or not it was concentrated. 324In Willoughby Municipal Council v Halstead it was accepted that the "ordinary impurities" would be present in the water. However the plaintiff in that case "proved" that the water that "actually passed through" the Council's pipe was "further contaminated by slop water and house refuse which in fact ran into the water-tables": per Griffith CJ at 357. 325The 200% increase in the stormwater runoff onto the Land over the years has come from the increased urbanisation of the catchment. I am satisfied that the plaintiff has proved that there are pollutants in the stormwater as identified by Dr Perrens. I am satisfied that the irresistible conclusion is that the untreated stormwater flowing onto the Land had the ordinary impurities within it and also some pollutants. 326The defendant submitted that because the plaintiff did not want to use the Land except for development purposes there was no unreasonable interference with the enjoyment of the Land by the presence of the stormwater runoff because it was just a "dormant" development site. The evidence in relation to the use to which the plaintiff put the Land whilst it awaited development approval establishes that over the years it was used for cattle grazing and horse agistment. It is clear that the plaintiff's contractors had to change the way they managed the Land because the Land became so soggy. I am of the view that the defendant's characterisation of the Land as "dormant" is misconceived. The defendant's argument that there was no interference with the enjoyment of the Land because it was "dormant", if accepted, would mean that any land within its jurisdiction that is presently awaiting development approval and not being used for any particular purpose could be categorised as "dormant" and utilised by the defendant with impunity to discharge its stormwater and/or create retention basins and/or perhaps to store some other by-product of its operations. I do not accept that simply because the plaintiff was not using the Land for a specific and continuous operation at any particular time from 2003 onwards means that there was no unreasonable interference with the enjoyment of the Land. 327The Land was in part converted into a retention basin for the water from the defendant's drains and from the NPE. This combined with the 200% increase in the stormwater runoff onto the Land changed part of the Land physically from a rather flat grazing property to a soggy watery expanse causing very serious interference with the plaintiff's enjoyment of the Land. Apart from losing the use of that part of the Land because it was covered in water, the plaintiff has had to instruct many consultants to obtain assistance with the preparation of a plan as to how the water should be drained from the Land. It has also had to construct table drains with the assistance of expert advice and at further cost to itself. 328I am satisfied that the plaintiff has established that there has been an unreasonable interference with its right to enjoy the Land. Defendant's knowledge/steps taken 329It is clear that the defendant decided to utilise the plaintiff's Land as a retention basin for the stormwater run-off in the area generally and it continued to do so after the letter of 5 March 2003. Mr Knight's memorandum of 27 February 2003 noted that the plaintiff's application for the shopping centre would "incrementally eliminate detention storage" in the Land and the filling would eliminate all detention storage from the Land. Mr Knight noted that the combined effect would be to "eliminate in excess of Q5 drainage capacity for the upstream catchment and cause flooding of land and property". He argued that the Land was the "natural area for runoff to be discharged from the foreshore dune area and acts as a natural detention basin for the foreshore dune area". The defendant was conscious that if it allowed development it would have to find some alternative for its retention basin for stormwater runoff. 330From 5 March 2003 the defendant became aware that the plaintiff was alleging that there was "unlawful" discharge of stormwater onto the Land. From 4 May 2004 the defendant must have been aware that the plaintiff was alleging that there was an unreasonable interference with the enjoyment of the Land. It was on 4 May 2004 that the plaintiff advised the defendant that Dr Webb had expressed the opinion that Turnock Street was acting as a dam for even small storm events and that adequate under-road and lateral drainage was required to ensure that unnatural ponding did not continue to the north of Turnock Street. 331The question then arises as to whether the defendant conducted itself to remedy the problem from that time without undue delay: Sutherland Shire Council v Becker at 226 [121]. If the defendant knew or ought to have known of the nuisance and the real risk of reasonably foreseeable consequential damage to the plaintiff, it had an obligation to take such positive action as a reasonable person in its position and circumstances would consider necessary to eliminate the nuisance: Robson v Leischke at 109-110 [48]-[52]. 332Although I have rejected as inapt the defendant's argument that there was no interference with the enjoyment of the Land because it was "dormant" and awaiting development, it is necessary to analyse the steps the defendant took or the position it adopted once it was put on notice that there was damming of the water north of Turnock Street and unnatural ponding. The defendant knew that it had imposed a number of conditions on the plaintiff as pre-requisites to development consent, including the production of an acceptable drainage plan. It knew that the culverts under Turnock Street were of no use to the drainage of the Land because they had been constructed to the level of the anticipated filled Land. The defendant did not take any steps to alleviate the damming of the water north of Turnock Street when it was notified in March 2003 and/or May 2004. I regard this as most unreasonable. It was left to the plaintiff to alleviate the problem by the construction of the table drain with the assistance of expert advice including that of Dr Webb. 333It was reasonably foreseeable that harm would be caused to the plaintiff by reason of: (1) the wetting up of the Land with untreated polluted stormwater; and (2) the need to find a method of accommodating the additional water. The defendant could not seriously resist the proposition that it was foreseeable that the wetting up of the Land may cause physical damage to the Land (tr 1291-1292). By May 2004 when the complaint was made the defendant knew that there were Wallum Froglets on the Land in "great abundance". 334The plaintiff claims that the defendant failed to take any steps to eliminate the nuisance once it was made aware of it. In fact the plaintiff claims that the defendant was well aware that it had caused the nuisance when it decided to establish the retention basin on the Land in 1995. There is no doubt that the additional water on the Land was caused by the defendant's inadequate drainage system as described earlier, however as I have already said it was not until March 2003 that the plaintiff decided not to tolerate the interference with its enjoyment of the Land. 335The plaintiff claims that the defendant has failed to react appropriately to this continuing nuisance. It claims that the defendant recognises that the nuisance continues; that it has approved the Blue Jay Circuit works that will rectify the problem; and it has failed to implement the approved solution. I agree that the defendant has recognised that there is a need to eliminate the increased flow of stormwater onto the Land. The defendant had recognised the "drainage problem" from as early as 1995 when it sought to find a "solution". It also knew from that time that there was a need for water quality control of the additional stormwater runoff onto the Land as reflected in its internal documents, for example, in the communication of 13 March 1995 referred to earlier (par 49). 336I am satisfied that from 5 March 2003 when the plaintiff notified the defendant that it would no longer tolerate the flow of stormwater onto the Land and certainly no later than 4 May 2004 when the plaintiff's solicitors complained of nuisance, the defendant was aware that the increased flow of water onto the Land may cause physical damage to the Land. Nuisance 337I am satisfied that the presence of untreated polluted stormwater runoff from the defendants' drains onto the Land constituted an actionable nuisance from 4 May 2004. 338The plaintiff contended that if the defendant had established table drains north of Turnock Street, as the plaintiff itself did in 2004, the stormwater could have drained away more effectively. The plaintiff accepted that since it established the table drain north of Turnock Street and cleared the Elrond Drive culvert, the water has drained away more effectively (Dr Webb's August 2010 report paragraph 8.3.24). However there are still problems after major storm events when the Land once again becomes inundated as shown in the photographs referred to above (and also Dr Webb's August 2010 report paragraph 7.5.7). The nuisance continues to this day in this regard but to a lesser extent, that is, confined to periods after major storm events. 339I am satisfied that the presence of the untreated polluted stormwater runoff on the plaintiff's Land constituted a nuisance from 4 May 2004 until some short time after the table drains were installed in 2004 and the water began to drain more effectively. I am satisfied that the nuisance continues and/or there is a separate nuisance after major storm events. Defences 340The plaintiff submitted that unlike in most negligence cases where the burden remains with the plaintiff throughout, once it is established that the defendant caused a nuisance, the defendant bears the onus of justifying its conduct or having its conduct excused: Brodie v Singleton Shire Council (2001) 206 CLR 512; [2001] HCA 29 at 567 [122] per Gaudron, McHugh and Gummow JJ citing Denning LJ in Southport Corporation v Esso Petroleum Co Ltd [1954] 2 QB 182 at 197 (reversed on other grounds in Esso Petroleum Co Ltd v Southport Corporation [1956] AC 218). The defendant accepted this position and relied on various provisions of the Civil Liability Act 2002 (the CLA), the Roads Act 1993 and s 733 of the Local Government Act 1993 (the LGA) to claim that it is not liable in respect of these nuisances. The defendant does not claim its actions should be excused on the basis of the "statutory authority" defence referred to by Giles JA in Melaleuca at [49]. Civil Liability Act 2002 (CLA) 341The plaintiff submitted that the policy found in sections 120 and 142A of the Protection of the Environment Operations Act 1997 (NSW) precludes the defendant from relying upon the operation of the CLA to justify or excuse its actions of depositing polluted stormwater on the Land. Section 120 of that Act makes it an offence to pollute any waters. "Water pollution" or "pollution of waters" is defined to mean the placing in or on, or otherwise introducing into or onto, waters "any matter, whether solid, liquid or gaseous, so that the physical, chemical or biological condition of the waters is changed". It also includes the placement or introduction onto the waters of "any refuse, litter, debris or other matter" likely to make the waters "unclean, noxious or harmful" or "undrinkable for farm animals" or "is likely to obstruct or interfere with persons in the exercise or enjoyment of any right in relation to the waters" includes making the water unsuitable for use in irrigation. Section 142A makes it an offence for any person to pollute land. "Land pollution" is defined as the placing in or on or otherwise introducing into or onto the land any matter "that causes or is likely to cause degradation of the land, resulting in actual or potential harm to the health or safety of human beings, animals or other terrestrial life or eco systems, or actual or potential loss or property damage, that is not trivial". 342The fact that the provisions of Protection of the Environment Operations Act define land pollution and water pollution and make it an offence to pollute land and water does not in my view prevent the defendant seeking to rely on the provisions of the CLA, if they are otherwise applicable. Part 1A of the CLA 343The defendant relied upon ss 5 and 5A of Part 1A of the CLA that provide as follows: PART 1A NEGLIGENCE ... 5 Definitions In this Part: "harm" means harm of any kind, including the following: ... (b) damage to property, (c) economic loss. "negligence" means failure to exercis e reasonable care and skill. ... 5A Application of Part (1) This Part applies to any claim for damages for harm resulting from negligenc e , regardless of whether the claim is brought in tort, in contract, under statute or otherwise. (2) This Part does not apply to civil liability that is excluded from the operation of this Part by section 3B. 5B General principles (1) A person is not negligent in failing to take precautions against a risk of harm unless: (a) the risk was foreseeable (that is, it is a risk of which the person knew or ought to have known), and (b) the risk was not insignificant, and (c) in the circumstances, a reasonable person in the person's position would have taken those precautions. (2) In determining whether a reasonable person would have taken precautions against a risk of harm, the court is to consider the following (amongst other relevant things): (a) the probability that the harm would occur if care were not taken, (b) the likely seriousness of the harm, (c) the burden of taking precautions to avoid the risk of harm, (d) the social utility of the activity that creates the risk of harm . 344Section 3B of the CLA makes no reference to nuisance. The section excludes cases that involve an intentional act done with intent to cause injury or death; sexual assaults or other sexual misconduct; claims for damages for dust diseases; claims in respect of injury or death resulting from smoking or other use of tobacco products; damages in respect of injuries suffered in motor accidents; claims for workers, and other, compensation. 345The plaintiff submitted that these provisions of the CLA are not applicable because negligence as defined is not an element of the tort of nuisance. The defendant submitted that even if this Part of the CLA is not applicable, the principles to be considered in deciding whether its actions were justified or should be excused are the same as those outlined in s 5B of the CLA. It has been suggested that to "the extent of the plaintiff bringing a claim for damages in nuisance must establish that the defendant has failed to exercise reasonable care and skill" Part 1A of the CLA will apply. However doubt was expressed as to whether the Australian common law continues to recognize any such instances other than perhaps in the case of support of land : Dominic Villa Annotated Civil Liability Act 2002 (NSW) Law Book Co 2004 [1A.5A.070]. 346I am of the view that the use of the expression "negligence" in s 5A, as defined in s 5 of the CLA, as the "failure to exercise reasonable care and skill" is limited to causes of action alleging negligence whether in tort, contract or under statute. This is a cause of action in nuisance that has imported into it some features of the duties that might otherwise be found in the tort of negligence. Damages are available for harm that is suffered by reason of the nuisance, the unreasonable interference with the enjoyment of land. The breach of duty in the tort of nuisance in this case, the failure to take reasonable steps to eliminate the foreseeable risk of damage from the nuisance, is different from the breach of duty or "negligence" defined in s 5 as the "failure to exercise reasonable care and skill". I am satisfied that Part 1A of the CLA does not apply. 347However I accept that the principles referred to in s 5B of the CLA are similar to those to be considered in determining whether the steps taken or the position adopted by the defendant were reasonable in all the circumstances: Leakey v National Trust for Places of Historic Interest or Natural Beauty [1980] 1 QB 485 at 524 per Megaw LJ. Part 5 of the CLA 348The defendant also relied upon ss 42, 43A and 45 of the CLA and submitted that these are in a different category to Part 1A of the CLA. These sections are all in Part 5 of the CLA entitled "Liability of Public and Other Authorities". Section 40 provides: 40 Application of Part (1) This Part applies to civil liability in tort. (2) This Part extends to any such liability even if the damages are sought in an action for breach of contract or any other action. (3) This Part does not apply to civil liability that is excluded from the operation of this Part by section 3B. 349This Part of the CLA extends to any civil liability (not excluded by s 3B) of a public or other authority even if the damages are sought in an action for breach of contract or any other action: Sydney Water Corporation v Turano (2009) 239 CLR 51 at 62 [14]. I agree with the defendant's submission that this Part of the CLA appears to be dealing with broader liability than the action in negligence referred to in Part 1A. However it will be necessary to separately consider the applicability of each section relied upon by the defendant. Section 42 of the CLA 350The first sections relied upon by the defendant are ss 41 and 42 in Part 5 of the CLA that relevantly provide: 41 Definitions In this Part: "exercise" a function includes perform a duty. "function" includes a power, authority or duty. ... 42 Principles concerning resources, responsibilities etc of public or other authorities The following principles apply in determining whether a public or other authority has a duty of care or has breached a duty of care in proceedings for civil liability to which this Part applies: (a) the functions required to be exercised by the authority are limited by the financial and other resources that are reasonably available to the authority for the purpose of exercising those function s , (b) the general allocation of those resources by the authority is not open to challenge, (c) the functions required to be exercised by the authority are to be determined by reference to the broad range of its activities (and not merely by reference to the matter to which the proceedings relate), (d) the authority may rely on evidence of its compliance with the general procedures and applicable standards for the exercise of its functions as evidence of the proper exerci s e of its funct i on s in the matter to which the proceedings relate. 351The defendant submitted that by operation of ss 41 and 42 of the CLA, its obligation to perform any duty is limited by resources reasonably available to it for performing those functions and the allocation of those resources is not open to challenge. It was submitted that the plaintiff's assertion that it was incumbent upon the defendant to expend millions of dollars of public funds eliminating the risk that the lack of a flow path for flood waters across NPE would result in damage to the Land and/or the creation of additional froglet habitat involves "challenging" the defendant's allocation of its resources which is prohibited by s 42 of the CLA. 352The defendant submitted that irrespective of whether or not s 42 operates in this way, an assessment of the reasonableness of the defendant's conduct in failing to undertake the Blue Jay Circuit project or its equivalent cannot be undertaken without also factoring into consideration the risk to the plaintiff that ought to have been in the defendant's contemplation and that ought to have been balanced against the expenditure to complete the work. It was submitted that it is relevant in that context to note that there was no complaint of ponding or saturation of the area in the vicinity of Turnock Street, associated with the inadequacy of the 1200mm pipe or otherwise, at any time prior to the discovery of the froglet population in 2003. I agree that there was no such "complaint" made by the plaintiff. However it is clear that the parties had been working towards a drainage strategy for the area. 353The defendant submitted that even if it is accepted that the creation of the ponds and the Wallum Froglet habitat were foreseeable, circumstances surrounding the breach of development conditions at NPE were not such as to suggest extensive works were required in order to avoid the creation of such ponding and habitat. Precisely the same issues arise in connection with the claim that additional culverts and table drains should have been constructed under and adjacent to Turnock Street. The defendant submitted that any such drainage was temporary and would be redundant when the land was filled. If the question of whether public resources should be expended in order to ameliorate the risk of the propagation of an endangered froglet species is to be considered, and even assuming that the risk was foreseeable, the defendant submitted that it cannot be regarded as having been in breach of a duty owed to the plaintiff in failing to expend funds on temporary drainage to address that risk. 354Finally, the defendant submitted that liability can only be established for a failure to address the blocked drains if it can be established that the defendant owed a duty to carry out routine inspections of such a nature and at such intervals as would have revealed the existence of the problem in time to avoid the creation of the froglet habitat. It was submitted that in light of the provisions of s 42(d) of the CLA that expressly permit the defendant to rely upon its general procedures (reactive maintenance of drains), the plaintiff's difficulties are insuperable. 355Mr Stephen Paff is an engineer and has been employed by the defendant as a "Maintenance Engineer" since 1994. His duties include responsibility for maintenance activities to public roads, bridges, stormwater, footpaths and associated infrastructure within the Tweed Shire; development and management of Asset Management Systems for road infrastructure; and management of road maintenance staff and budgetary control. Mr Paff gave evidence that in January 2003 the defendant adopted a "Strategic Asset and Service Management Program" which was devised by an independent risk management firm. That program included the following: 14.26.2 Preventative or Routine Maintenance Inspection No preventative or routine maintenance inspection of any stormwater or drainage system shall be carried out. 14.26.3 Technical Inspections A technical inspection of stormwater or drainage systems shall be carried out: as and when determined necessary; and at a level and standard; determined by a responsible person. 356In cross-examination Mr Paff agreed that a "Drainage Assets Management Plan" (Ex 3) had been drafted in 2009 but that the defendant had not yet adopted it (tr 1007). In the "Stormwater Drainage Maintenance Service Level Manual" (Ex 4) there is reference to "Proactive Inspections" which are said to be "As per Council 'Proactive Inspection Schedule' in Maintenance Manual". However this Manual also provides that "Pipes will be inspected on a needs basis". The Drainage Assets Management Plan includes the following: 5.5 Maintenance Inspections of Drainage Assets The frequency of proactive and reactive maintenance inspections is undertaken as per the frequency, documented in Council's maintenance levels of service. ... 5.11 Routine Maintenance Over time, minor faults can occur within the Drainage network. Tweed Council addresses the repairs and maintenance of these faults on the basis of defined intervention levels and response times. The intervention level defines the condition, state or risk level associated with an asset component, i.e. the point in time at which the asset is considered to be below an acceptable level of service. Maintenance is scheduled as soon as the asset reaches this point Response time defines a reasonable timeframe within which the residents can expect the Tweed Shire to remedy the defect. The intervention levels and response times are contained in the Shire's maintenance levels of service documents, (available for inspection at Council's offices). 357The Drainage Assets Management Plan also includes a section on costing in particular an historical overview of the capital expenditure between 2005 and 2009 on certain "Capital Activity" being drainage asset management, drainage construction and stormwater drainage rehabilitation. That history records total capital expenditure in 2005/06 of $199,050, in 2006/07 of $1,377,854, in 2007/08 of $1,929,478, and in 2008/09 of $1,749,094. The total "Operation and Maintenance Activity" expenditure is recorded as $854,497 in 2004/05, $1,192,825 in 2005/06, $1,273,912 in 2006/07 and $1,615,204 in 2007/08. 358Mr Paff gave evidence that there is no proactive maintenance of stormwater infrastructure. It is only inspected on a complaints basis (tr 1005). Mr Paff has only been aware of complaints by the plaintiff about the wetting up of its Land since 2007. He was not aware of complaints by the plaintiff prior to that date (tr 1040). That may be so but it is clear that from 5 March 2003 the plaintiff had complained that there was unlawful discharge of concentrated stormwater onto the Land from the Council's drainage structure. It is not clear why Mr Paff was not made aware of the plaintiff's complaints in this regard. 359Mr Paff was cross-examined in relation to the Roads and Traffic Authority (RTA). He said that responsibility for roads are allocated to the defendant under the Roads Act and that the defendant is the roads authority for most regional roads other than expressways and motorways. The defendant has the legal responsibility under that Act for maintaining both regional and local roads (tr 1053). Mr Paff agreed that for the maintenance of regional roads the RTA provides a block grant. The defendant also receives funding from the Federal government by way of untied financial assistance grants that it can spend on local roads (tr 1054). Every year the defendant receives $400,000 for stormwater repairs as part of a seven-year plan (tr 1055). Elrond Drive is a "road drain" (tr 1056). Kerb and gutter and table drain clearing have always been costed to road maintenance and not to stormwater (tr 1057). 360A print out from the defendant's webpage, downloaded on 18 March 2011, (Ex SS) includes the following: West Kingscliff Drainage $2,000,000 The stormwater drainage outlet for part of Kingscliff (behind the southern section of Kingscliff Street and northern section of Pearl Street) has been partially blocked by filling associated with past subdivision development in West Kingscliff. The pipes that drain this area are only big enough for a 1 in five year storm. A larger outlet is needed for bigger storms. If this is not provided there is likely to be periodic stormwater flooding of some property, and residences in this part of Kingscliff. Council may be exposed to liability claims if this outlet is not provided. 361Mr Paff did not know the origin of part of this entry on the defendant's webpage (tr 1059). He is provided with a budget for the year's works and if there is a need to go outside that budget to deal with an urgent drainage issue he reports that to his next level of management. There is then a budget review. He agreed that he had exceeded his budget from time to time (tr 1061). What usually happens is that money is reallocated from other programs within the total budget so that the total budget stays the same but activities change (tr 1061). 362The plaintiff submitted that s 42 of the CLA is premised upon a judicial consideration of a "duty of care" and can have no application in relation to the present claim, which is based in nuisance and not in negligence. It was submitted that this is sufficient to dispose of the so-called "defence" under s 42 of the CLA. Although Part 5 may be applicable to wider claims than negligence, including nuisance, the provisions of s 42 deal specifically with a duty of care. The "duty" imposed on the defendant in the tort of nuisance is not in the circumstances of this case (where the defendant caused and was notified of the nuisance) a "duty of care" but a duty to take reasonable steps to eliminate the nuisance. It is conceivable that in taking steps to eliminate a nuisance a duty of care may be separately imposed on a defendant the breach of which would expose it to a suit in negligence. I am satisfied that the plaintiff's submission that s 42 is inapplicable to this case should be accepted. That is not to say that in considering whether the defendant took reasonable steps to eliminate the nuisance I should not have regard to matters that are reflected in s 42 of the CLA. 363The plaintiff also submitted that the two distinct aspects relied upon by the defendant are the resource limitations in relation to carrying out drainage works and compliance with procedures for maintenance of drainage works. In respect of the resource limitations the plaintiff relied upon what was said in Sydney Water Corporation v Turano at 65 [27] that the defendant must lead evidence of its financial or other resources so as to raise the operation of the section. The plaintiff submitted that the evidence led from Mr Paff did not establish any financial limitations on the defendant. I agree with that submission. 364The plaintiff relied upon two reports from Gary Frederick Mottau an accountant with experience of working in local government. Mr Mottau worked as the principal accounting officer at Warringah Shire Council for nine years and is now the principal of the accounting firm Hill Rogers Spencer Steer. In his reports (Ex TT) Mr Mottau analysed the financial statements of the defendant for the year ending 30 June 2010. He concluded that the operating result for the year was a surplus of $9.005 million and that it had excess available funds of $10.414 million. Its available working capital was $6.816 million. Mr Mottau noted that the defendant had unanimously adopted the Quarterly Budget Review statement as at 31 December 2010 at its ordinary meeting held on 15 February 2011. That report discloses the projected Available Working Capital as at 30 June 2011 to be $6.069 million. Mr Mottau analysed the variations in the General Fund and concluded that the changes demonstrated a considerable discretion in allocating funds to and from the capital works program during the year. Mr Mottau's conclusion was that the defendant has access to a number of sources of funding in the short term to carry out additional stormwater drainage works without adversely impacting its key financial performance indicators. 365In cross-examination Mr Mottau was taken to the financial statements of the defendant for the year 2009/10. The non-cash contributions for water at $2.395 million, sewage at $5.834 million together with dedications for roads at $2.936 million, drainage at $1.532 million and open space at $1.814 million were drawn to his attention. He gave the following evidence (tr 1160): Q. But the simple proposition is that a non-cash contribution is in the nature of a dedication of an asset; it doesn't provide funds from which the council can fund its activities, correct? A. Well, it doesn't stop a council from disposing of that asset and using the funds to carry out its activities, as long as it goes through the process on which the asset has been provided to the council, and councils have done that. Q. You wouldn't expect that road and drainage dedications would be capable of being realised in the course of the management of the council's activities and used to fund its expenditure would you? A. Your Honour, what has happened - it has happened in the past, I know of examples where councils have closed roads, sold with approval under the Roads Act, and used those funds for the purposes of which the council saw fit. 366Mr Mottau was cross-examined in relation to the suggestion that the defendant was not able to fund depreciation from its revenue. He gave the following evidence (tr 1162): Q. What this demonstrates is that it is unable to fund its depreciation from its revenues in 2010, isn't it? A. From its operating revenue, yes. Q. And the surplus shown, five lines further down is after capital grants and contributions of $24.4 million, correct? A. That's correct. Q. And those that council is not at liberty to expend those capital grants and contributions in any way it wishes, is it? A. No, there are often conditions attached to those grants and contributions. Q. We have seen that a substantial proportion of the $24.4 million capital contribution is in the form of noncash capital grants and contributions, correct? A. Correct. Q. Any capital contributions from a section 94 plan would be tied to whatever project was related to the section 94 plan, correct? A. Correct. Q. And capital grants and contributions from government agencies are frequently tied to particular types of projects, for example road projects from road authorities, correct? A. Yes. 367Mr Mottau was cross-examined in relation to the criteria published by the Department of Local Governments (DLG) including an indicator for the ratio of current unrestricted assets to current unrestricted liabilities. He was also cross-examined in relation to the way that he used that information as follows (tr 1163-1166): Q. The proposition that I put to you is that that isn't an exercise by which you can meaningfully make an assessment of the amount of funding available to the council or excess funding available to council to fund additional projects such as drainage projects, is it? A. I think it is a very good indicator, in fact the DLG has it as the number one indicator. Q. The DLG has it as an indicator of the current state of financial health of a council, correct? A. It does, yes. Q. It doesn't use it to calculate what amount of, as you describe it, excess available funds a council has for funding such things as drainage projects, does it? A. It can be used for that purpose. Q. You have used it for that purpose, the DLG doesn't use it for that purpose? A. I am not aware what the DLG uses it for other than to provide comparative data. Q. It is not an appropriate means of identifying excess available funds for things such as drainage projects because the ratio rates only to current assets that are not the subject of external restrictions, doesn't take into account internal restrictions, does it? A. No it doesn't but internal restrictions are the discretion of the council. Q. Yes and the discretion of council in imposing internal restrictions as you understand it and in your experience is exercised as part of a proper and prudent management of the council's affairs, isn't it? A. That's correct. ... Q. You did describe the amount of reduction in the current assets that this council could endure without falling into the unsatisfactory category as excess available funds, correct, in paragraph (b)(ix) of your report? A. I described it as being, that's correct, excess available funds given that calculation, yes. Q. They are not excess available funds in the sense of being available to use on things such as drainage projects if those funds are subject to internal restrictions, are they? A. Your Honour they are. Internal restricted assets as you see at the discretion of council and can be changed at the next council meeting. Q. And if we make the assumption that the internal restrictions were placed on those funds in the exercise of the careful and prudent management of the council's affairs then you wouldn't expect council to do that, would you? A. That's given the assumption that is what those, I haven't made an assessment, I think the Court should know I haven't conducted an audit of council's financials and haven't referred to their internally restricted cash. I am merely using the DLG as a headline indicator for indicating that an excess of current assets existed as at that 30 June 2010 given the published financial data. ... Q. And of that amount only $1.91 million is unrestricted cash, that's the position, isn't it. A. In relation to cash it is. Q. You would expect things such as drainage works and drainage maintenance carried out by council to be funded from its general fund resources? A. Yes. Q. And you would expect it to be funded from cash resources wouldn't you? A. Cash is one source. There are debtors of nine and a half million dollars which are readily realisable to cash, there are inventories, there are other sources that make up current assets other than just cash. Q. We will come to your calculations in relation to current assets in a moment. The proposition that your calculation at paragraph 14(b) of the report identifies excess available funds of $10.4 million is, I suggest to you, a little rash in light of the fact that council had available to it as at the balance date only $1.91 million in unrestricted cash, do you agree with that? A. I don't agree with that. ... Q. And you have identified there that available working capital of the council as at the balance date stood at 6.816 million? A. Correct. Q. That is primarily a function, isn't it, of an exercise of comparison between the balance of payables and the balance of receivables, correct? A. No, it isn't. The net current assets of the council which is looking at current assets less current liabilities on the face of the balance sheet would indicate that council's net current assets is $132 million. My calculation over the page is where I go through adjusting for the restrictions that are placed on those assets to come up with the net result of $6.8 million dollars (sic). ... Q. Receivables in the form of resources in the form of cash when council receives the payment expected? A. Yes. Q. And the amount of the cash available at any particular time will depend upon timing of the performance by the council of its obligations and in connection with its payables? A. Yes. Q. The available working capital as at 30 June 2010 insofar as it comprised cash resources still only comprised the $1.9 million in unrestricted cash that we identified a few minutes ago, didn't it? A. Yes, that is $1.9 million would be a component of that 6.8. Q. And there was no other component of that $6.8 million as at the balance date that represented a resource available to the council to pay for drainage maintenance or infrastructure works? A. Well, on the contrary your Honour, I think that any organisation, councils included, any business uses its working capital to build its budget for the next year and as at that time its my assessed view that council had $6.8 million to build its budget for the next year. Now, that would include, that's access to things like receivables less the amount it owes in creators and you would expect in the normal course of time, within a year, otherwise it wouldn't be classed as current asset or liability, that there was an excess to the extent of $6.8 million to build its, to add to its budget for the following year. 368Mr Mottau agreed that there are difficulties associated with increasing the revenue needed to service borrowings on the general fund (tr 1169). He also accepted that he had not conducted an analysis that would enable him to make any comment on whether in the prudent operation of the defendant's activities it would be sensible to increase the debt service ratio. He made clear that he was not suggesting that one of the variations that the defendant might consider was additional funds. Rather he suggested that the defendant has a discretion to allocate funds within its budget to different priorities (tr 1170). 369Mr Mottau's evidence and reports are not a challenge to the way in which the defendant has structured its financial activities. Rather it demonstrates that there is a capacity to meet the cost for the completion of the Blue Jay Circuit project that would eliminate the nuisance on the Land. 370As to the procedures of reactive maintenance referred to in the evidence of Mr Paff, the plaintiff submitted that the defendant has not complied with the procedures. The plaintiff complained that the defendant failed to call its General Manager, Mr Rainer, or its Director of Engineering Services, Mr Knight. It was submitted that in the result the evidence does not support an assertion that there are any relevant general procedures with which the defendant has complied for the purpose of s 42(d) of the CLA or otherwise. 371The evidence of Mr Paff and Mr Mottau does not support the conclusion that there are real financial constraints on the defendant. Even taking into account the broad obligations that the defendant has to the general community in the area, I am satisfied that once it became aware of the withdrawal of the permit by the plaintiff it was able to create a plan to eliminate the nuisance, being the Blue Jay Circuit scheme, but failed to implement it. There is no real challenge to the way that the defendant has allocated its resources. The fact of the matter is that the defendant had an obligation to take steps to eliminate the nuisance that it had created over the years, tolerated by the plaintiff for many years, but in respect of which it had an obligation to rectify from 4 May 2004. 372In conclusion I am satisfied that s 42 does not apply to the circumstances of this case and even if it did I am not satisfied that the evidence supports the conclusion that the defendant's failure to take steps to eliminate the nuisance and/or nuisances is justified or should be excused by reason of any financial constraints on the defendant. S 43A CLA 373Section 43A relevantly provides: 43A Proceedings against public or other authorities for the exercise of special statutory powers (1) This section applies to proceedings for civil liability to which this Part applies to the extent that the liability is based on a public or other authority's exercise of, or failure to exercise, a special statutory power conferred on the authority. (2) A "special statutory power" is a power: (a) that is conferred by or under a statute, and (b) that is of a kind that persons generally are not authorised to exercise without specific statutory authority. (3) For the purposes of any such proceedings, any act or omission involving an exercise of, or failure to exercise, a special statutory power does not give rise to civil liability unless the act or omission was in the circumstances so unreasonable that no authority having the special statutory power in question could properly consider the act or omission to be a reasonable exercise of, or failure to exercise, its power. 374The defendant submitted that all of the alleged acts of nuisance concern exercises or failures to exercise "special statutory powers" within the meaning of s 43A of the CLA. The conduct in relation to the conditions imposed in respect of the filling the Northern Drain and the extension of Lorien Way concerned the defendant's approval powers under the EPA Act. The failure to inspect and maintain the 1200mm pipe concerned the defendant's failure to exercise either its Roads Act powers or its drainage powers under s 59A of the LGA. It was submitted that the failure to eliminate the nuisance was a failure to exercise a special statutory power within the meaning of s 43A of the CLA. 375Additionally it was submitted that the construction of Turnock Street with inadequate culverts and without table drains concerned the defendant's exercise of its approval powers under Part V of the EPA Act and its Roads Act powers in constructing and failing to maintain the culvert. It was submitted that all of this conduct involved the exercise or failure to exercise "special statutory powers". 376The defendant contended that it learned of an inadequacy in the design and construction of the 1200mm pipe after it had released the linen plan in respect of the NPE. It approved the Martin Findlater design before its receipt of the WMB draft drainage strategy providing for the lateral drain. It contends that between 1994 and 1997 it took reasonable steps to amend DCP 9 to provide for a detention basin solution as recommended by Mr Findlater in 1995. In 1997 it constructed Turnock Street providing a low level culvert for overflows from the 1200mm inlet in accordance with the design produced by an independent consultant engineer. 377The defendant submitted that at the time Turnock Street was constructed, flows of stormwater to the southern end of the Land might reasonably have been expected every five years or so, perhaps every few years, but it had not been identified by anyone as a likely frequent occurrence. It was submitted that it is also important to bear in mind that the drainage problems that were said to have occurred in the vicinity of Turnock Street substantially disappeared when basic maintenance was carried out to the plaintiff's drains. The defendant also submitted that it had no reason to anticipate that the plaintiff would not assume responsibility for the maintenance of its own drains and consequently the defendant had no reason to anticipate that the construction of Turnock Street would injure the plaintiff. The complaints regarding the design of Turnock Street relate to the absence of table drains and the provision of only one low lying culvert. It was submitted that given the circumstances that further low level culverts and table drains would be rendered obsolete when the Land was filled, and given that any substantial impediment to the use of what was then an unoccupied development site was not readily obvious, acceptance of a proposal from a consultant engineer which served to reduce the cost to the public of building a road in that fashion was manifestly reasonable conduct. 378The plaintiff submitted that s 43A(2) has two components, first that a "power" be conferred under a statute, and secondly that a power is of the kind that "persons generally are not unauthorised to exercise without specific statutory authority". It was submitted that the so-called "powers" identified by the defendant do not satisfy these requirements. For example an approval of a development, such as NPE, might involve several powers. It could be the grant of development consent, building approval, sub-division approval, a construction certificate, a sub-division certificate and so on. It was submitted that at least three different statutes are potentially involved: the Local Government Act 1919 (applicable until 1994, except for sub-division approvals, which continued in force until 1 July 1998); the LGA and the EPA Act. 379It was submitted that s 43A calls for a complex evaluative exercise requiring the Court to consider the particular exercise of the identified special statutory power and to consider its contextual reasonableness. It was also submitted that the Court must consider the extent to which the special statutory power is "involved", if at all. It was contended the defendant's attempt to activate the defence at a high level of generality is inadequate and should be rejected. 380Precision Products (NSW) Pty Ltd v Hawkesbury City Council (2008) 74 NSWLR 102; [2008] NSWCA 278 was a case in which the Council sought the protection of s 43A of the CLA in respect of the alleged negligent exercise of power under the Protection of the Environment Operations Act 1997 said to have caused damage to the appellant's business. Allsop P, with whom Beazley and McColl JJA agreed, said it was not appropriate to express a concluded view about the meaning and effect of s 43A. The learned President observed that the wording of s 43A(3) has "its source in what is often referred to as "Wednesbury unreasonableness" from Associated Provincial Picture Houses Ltd v Wednesbury Corporation [1948] 1 KB 223 at 229-230". His Honour also said at 141 [177]: Whether it is appropriate to describe s 43A as encapsulating the blunt expression of "gross negligence" is a matter for debate. However, it is plain that the drafter of s 43A was attempting to ameliorate the rigours of the law of negligence. 381The High Court has noted the "uncertain reach of s 43A": Sydney Water Corporation v Turano at 65 [26]. Notwithstanding this uncertainty and perhaps the limitation of the section to ameliorating the law of negligence rather than nuisance, I am going to assume that it applies to the consideration of whether the defendant took reasonable steps to eliminate the nuisance. 382The plaintiff submitted that there is a more fundamental difficulty with the defendant's attempt to rely upon this section. The plaintiff's claim against the defendant is one brought in nuisance by reason of the continuing operation of the stormwater drainage network. The defendant performs many functions and has many duties. Relevantly it is the drainage authority for drainage, including stormwater drainage. Section 43A speaks of a "special statutory power", not the exercise of a function or a duty. It was submitted that it is the narrower exercise of, or failure to exercise, that power. The LGA and the defendant's policies required developers to vest in the defendant the legal title to the drainage network. It was submitted that the defendant needed no special power to inspect or maintain its own land. The proposed works for Blue Jay Circuit entailed upgrading the existing corridor and no "special" statutory powers are required to do that. It was submitted that therefore the circumstances of this case do not involve the exercise of or a failure to exercise identifiable special statutory powers. 383The defendant's obligations to its constituents are complex and overlapping. In exercising its powers to require an applicant for development approval to conduct various impact studies, it has regard to numerous and varied attributes of the particular community. It exercises powers under the various statutes referred to above to enable the implementation of drainage strategies that may complement one property but be adverse to another. It has to balance numerous interests and community priorities in a fair and transparent manner. 384The plaintiff must establish that "the act or omission was in the circumstances so unreasonable that no authority having the special statutory power in question could properly consider the act or omission to be a reasonable exercise of, or failure to exercise, its power". The defendant contended that the plaintiff cannot satisfy this test on the evidence. The plaintiff submitted that the factual matters upon which it relies justifies a finding that the defendant's conduct was unreasonable in the Wednesbury sense. Those matters included: the failure of the defendant to inform the plaintiff that it had permitted the extension of Lorien Way without provision for the Northern Drain to flow under it; that it filled or permitted the Northern Drain to be filled without the construction of an adequate alternative drainage route for the stormwater runoff; and that it had instructed WBM not to address problems raised by it and by Knobel Consulting in relation to the 1200mm pipe. It was submitted that the defendant knew of the problem with the 1200mm pipe well before the release of the NPE linen plans. 385These matters, although factually correct, relate to conduct that caused the unreasonable interference with the plaintiff's enjoyment of the Land. They are matters concerning the creation of the nuisance rather than steps taken towards its elimination. The question to be decided is whether, after the plaintiff advised the defendant of the nuisance in May 2004, did the defendant take reasonable steps to eliminate the nuisance. The plaintiff submitted that the defendant has taken no steps to eliminate the nuisance. The plaintiff mitigated the harm itself by the creation of the table drains. It designed around the problems, at its own cost, and complained to no avail. In all the circumstances it was submitted that no reasonable Council would act in the manner that the defendant has acted. Rather it was submitted that a reasonable Council would have taken steps to eliminate the flow of stormwater onto the Land. 386I accept that the defendant took the view that the plaintiff planned to develop the Land and that it would be necessary to fill the Land to the level at which the culverts under Turnock Street were constructed. I accept that is why the culverts were designed and constructed at the level to accommodate the fill. The defendant's conduct suggests that it had anticipated the plaintiff would move more promptly than it has been able to in developing the Land. However the defendant burdened the plaintiff with the additional stormwater runoff when NPE breached its obligations. It then imposed a condition on the plaintiff that before any development consent would be granted the plaintiff was required to submit an acceptable drainage plan to remove the additional stormwater. Accordingly the timing of the development consent was in part in the defendant's control. 387When the plaintiff withdrew the permit in March 2003 and from 4 May 2004 when it advised the defendant that there was an unreasonable interference with its enjoyment of the Land, the defendant was obliged to take reasonable steps to eliminate the nuisance. Mr Knight's memorandum of 27 February 2003 is instructive. It is clear that the defendant regarded any development of the Land as a removal of its stormwater drainage storage capacity, that is, it would inhibit the defendant's capacity to use the Land as a retention basin for the stormwater run-off. This use had been without any compensation to the plaintiff. 388Once the plaintiff complained and withdrew the permit the position between these parties changed. The defendant had created the nuisance and it did not take any steps to eliminate the nuisance. It has a plan, the Blue Jay Circuit Scheme, that will eliminate the nuisance but it will not implement it until it receives a contribution from the Nursing Association. In the mean time the plaintiff has had the burden of the cost and inconvenience of retaining experts to assist it to mitigate the harm to the Land by the creation of the table drain in 2004 and commencing and pursing these proceedings to prompt the defendant into taking steps to eliminate the nuisance. 389The vagaries of the development of land are such that any reasonable Council would know that there is always uncertainty about the time within which a development may be approved and/or constructed. The longer there was no development of the Land, the longer the defendant was able to utilise the Land as a retention basin. That seemed to be Mr Knight's attitude in February 2003. That position remains the same today, eight years after the plaintiff made it very clear that it was no longer willing to tolerate the additional stormwater runoff onto the Land. 390I am satisfied that no reasonable Council would act in the manner that the defendant has acted after it was notified by the plaintiff that it would no longer tolerate the inundation of the Land with the additional stormwater runoff. I am also satisfied that to decide on a scheme that will eliminate the nuisance but not implement it and not take any other steps to eliminate the nuisance is so unreasonable that the defendant does not have the benefit of s 43A(3) of the CLA to justify or excuse its conduct. 391As I have said above, in considering the application of s 43A of the CLA, I regarded the relevant conduct of the defendant to be the steps it took after being notified of the nuisance. However if that is wrong and the relevant consideration includes the original conduct that caused the wetting up of the Land, I am satisfied that no reasonable Council would act in the way the defendant acted. To burden the innocent neighbour, the plaintiff, with the retention basin on its Land for the consequence of the breach of NPE, without advising it of the true reason for its need and without any proposal for compensation and then requesting it to fund expert surveys on drainage of the area in the amount of approximately $21,000 (albeit that there was some suggestion of later s 94 credits in respect of this amount), is in my view extremely high-handed and unreasonable. The defendant does not have the benefit of s 43A to excuse or justify its conduct. S 45 CLA 392The defendant also relied on s 45 of the CLA which provides: 45 Special non-feasance protection for roads authorities (1) A roads authorit y is not liable in proceedings for civil liability to which this Part applies for harm arising from a failure of the authority to carry out road work, or to consider carrying out road work, unless at the time of the alleged failure the authority had actual knowledge of the particular risk the materialisation of which resulted in the harm. (2) This section does not operate: (a) to create a duty of care in respect of a risk merely because a roads authority has actual knowledge of the risk, or (b) to affect any standard of care that would otherwise be applicable in respect of a risk. (3) In this section: "carry out road work" means carry out any activity in connection with the construction, erection, installation, maintenance, inspection, repair, removal or replacement of a road work within the meaning of the Roads Act 1993 . "roads authority" has the same meaning as in the Roads Act 1993 . 393The defendant submitted that it was the relevant "road authority" for all public roads within the Tweed Shire and was responsible for the roads including Pearl Street, Quigan Street, Elrond Drive, Turnock Street and Lorien Way. The defendant also submitted that all of those roads and the drainage constructed within the roads were public roads for which it was the relevant road authority. 394Section 45 of the CLA applies to "civil liability in tort" and for the same reasons as submitted in respect of s 43A, the defendant contended that it applies to an action in nuisance. 395A road authority is not liable for failure to carry out "road work" unless at the time of the alleged failure the authority had "actual knowledge of the particular risk the materialisation of which resulted in the harm": The relevant risk is the physical condition which creates the risk: North Sydney Council v Roman (2007) 69 NSWLR 240; [2007] NSWCA 27 at 272 [157] and 277 [186] per Basten JA, Bryson JA agreeing. 396The defendant submitted that in this case the relevant physical condition alleged against it is the blockage and/or incapacity of the Elrond Drive culvert. The first complaint of incapacity of the Elrond Drive culvert was on 4 May 2004 in the plaintiff's solicitor's letter to the defendant. It was submitted that s 45 operates to protect the defendant, as by the time the Froglet was established in 2003, the defendant did not have actual knowledge of the alleged incapacity. However the presence of the ponding of the water per se (the non-frog case) was well known to the defendant at the time of the complaint and the knowledge of the presence of the additional stormwater runoff on the Land would carry with it an understanding that such presence could cause physical damage to the Land, irrespective of the presence of the Wallum Froglets. 397It was submitted that the plaintiff has not proved that the defendant actually knew that the Elrond Drive culvert was blocked or drainage through it was impeded at any time before 4 May 2004; that there was any risk of ephemeral ponding of sufficient duration to create a habitat suitable for the Wallum Froglet to establish a viable local population north of Turnock Street; and that there was any blockage or impediment downstream of the Elrond Drive culvert affecting the drainage through the culvert. Accordingly it was submitted that the defendant is protected by the immunity from any civil liability in tort arising from any blockage of that culvert or in any part of the road and road reserve. 398The plaintiff submitted s 45 of the CLA creates "special" non-feasance protection for "roads authorities". The plaintiff submitted that the defence has no application to the present case for three reasons. First, the provision only protects a "roads authority": Buckle v Bayswater Road Board (1936) 57 CLR 259 at 273. In the present case the defendant is sued by reason of its function as a landowner and a drainage authority. However assuming non-feasance, the plaintiff submitted that the work which was not done was not the carrying out of "road work" in the capacity of the defendant being the roads authority. The special protection given by s 45 of the CLA cannot be called in aid generally by an authority carrying out functions in a different capacity. Secondly, the installation of the 1200mm pipe and the Elrond Drive culvert was not "road work" within the meaning of the Roads Act 1993. Thirdly, the complaint is in relation to the design of the drainage, the incapacity of the 1200mm pipe and the inadequacy of the Elrond Drive culvert and is not a complaint arising from a failure "to carry out road work" within the meaning of s 45 of the CLA. 399Section 146 of the Roads Act 1993 provides: 146 Nature of ownership of public roads (1) Except as otherwise provided by this Act, the dedication of land as a public road: (a) does not impose any liability on the owner of the road that the owner would not have if the owner were merely a person having the care, control and management of the road, and (b) does not affect the rights or liabilities of any person under any easement or under any Act or law, and ... (d) does not constitute the owner of the road as an occupier of the land, and ... (2) This section does not restrict the power of a roads authority to regulate the digging up of public roads pursuant to the provisions of any other Act. 400It was submitted that the Roads Act does not exclude the liability of the defendant by virtue of its ownership of the land and the drains which run through the Road. It was further submitted that the correct interpretation is that the culvert was not "road work" because its construction was undertaken by reason of the defendant's duties as a drainage authority under the LGA and not "for the purpose of facilitating the use of the road as a road": Roads Act Dictionary, "road work". 401It was submitted that in this context the defence can only apply to a roads authority. The activity about which the plaintiff complains was not the conduct of the roads authority but of the defendant in managing its stormwater system. The plaintiff submitted that there is no doubt, according to Mr Paff's evidence, that the defendant manages the stormwater system separately from its road programs. Of critical significance was Mr Paff's evidence that drainage culverts, as distinct from table drains, were not funded from the roads budget or managed as part of the road (tr 1056-1057). The roads authority itself does not manage culverts as part of the road. It was submitted that the defendant cannot make good the predicate for the defence because it does not manage the culverts in its capacity as a roads authority. 402The plaintiff submitted that the inlet to the 1200mm pipe is not in a road way. It does not form any part of a road and is under a pathway dedicated as such. The language of the instrument (Ex XX) compels the conclusion that the path was not dedicated as a public road and the defendant does not need any special powers to maintain it. The plaintiff submitted that the pathway and the pipe vested with the pathway upon the registration of the plans for that stage of the NPE. 403The plaintiff submitted that s 45 of the CLA only requires actual knowledge of the particular risk and not the harm or its materialisation. It was submitted that the defendant knew its drains were poorly designed and were inadequate. It was aware from the drainage investigations by WBM in 1998 and by Knobel in 2001 that its drains were causing drainage problems. It was submitted it therefore had actual knowledge of the risk that the drains would fail. It was submitted that in any event because the legal onus is on the defendant to excuse its conduct, it is required to establish, at the minimum, absence of actual knowledge. The plaintiff emphasised the absence of Mr Knight and Mr Rainer as witnesses and submitted that the defendant had failed to discharge the onus. 404I agree with the plaintiff's submission that the drainage system maintained by the defendant is not "road work". However even if the failure to install the culverts under Turnock Street and the additional pipes provided for in the plans for Elrond Drive could be categorised as "road work", the defendant was well aware that it had decided to use the Land as a retention basin and as such had actual knowledge of the risk at the time, of the increased volumes of untreated stormwater on the Land, that resulted in the harm. 405Assuming the defendant is a roads authority and the Blue Jay Circuit Scheme is "road work", it is quite clear that the defendant knew, certainly from 4 May 2004, that there was a risk that harm to the Land by the increased stormwater on it would result from its failure to carry out the road work. The defendant's conduct is not justified or excused by the provisions of s 45 of the CLA. Section 733 LGA 406The defendant claims that it has at all times acted in good faith in its drainage works. In this regard it relies upon s 733 of the LGA which provides as follows: 733 Exemption from liability-flood liable land, land subject to risk of bush fire and land in coastal zone (1) A council does not incur any liability in respect of: ... (b) anything done or omitted to be done in good faith by the council in so far as it relates to the likelihood of land being flooded or the nature or extent of any such flooding. ... (3) Without limiting subsections (1), (2) and (2A), those subsections apply to: (a) the preparation or making of an environmental planning instrument, including a planning proposal for the proposed environmental planning instrument, or a development control plan, or the granting or refusal of consent to a development application, or the determination of an application for a complying development certificate, under the Environmental Planning and Assessment Act 1979 , and ... (c) the imposition of any condition in relation to an application referred to in paragraph (a), and ... (g) any other thing done or omitted to be done in the exercise of a council's functions under this or any other Act. (4) Without limiting any other circumstances in which a council may have acted in good faith, a council is, unless the contrary is proved, taken to have acted in good faith for the purposes of this section if the advice was furnished, or the thing was done or omitted to be done, substantially in accordance with the principles contained in the relevant manual most recently notified under subsection (5) at that time. (5) For the purposes of this section, the Minister for Planning may, from time to time, give notification in the Gazette of the publication of: (a) a manual relating to the management of flood liable land, or (b) a manual relating to the management of the coastline, or (c) a manual relating to the management of land subject to the risk of bush fire. The notification must specify where and when copies of the manual may be inspected. 407The defendant submitted that ponding of water of the kind alleged by the plaintiff falls within the meaning of "flooded" or "flooding" in s 733: Melaleuca Estate at 341-342 [78] to [80] per Giles JA. The existence of good faith must be proved by the defendant as an attribute of the negligence which excuses liability. Good faith must be more than honest ineptitude: Mid Density Developments Pty Limited v Rockdale Municipal Council (1993) 44 FCR 290. 408It is conceded that in 1994 the defendant recognized the need for a drainage strategy that accommodated the whole of the Kingscliff area in accordance with DCP 9. The defendant commissioned consultants to produce such a strategy. When Mr Hill produced the drainage report for the Bowls Club, the defendant provided it to Mr Findlater who refuted its conclusions relating to the catchment size and the allowance for the Q100 flow. In early 1995 Mr Findlater produced an Alternative Drainage Strategy that presented the three alternatives referred to earlier with a recommendation that the retention basin was the most economical alternative. The defendant claims that it encouraged the plaintiff to propose further designs in relation to a final drainage solution but that this encouragement was met by the plaintiff's requests to delay the changes to DCP 9 until it prepared a "master plan" for all of the plaintiff's landholdings in the Kingscliff area. 409The plaintiff submitted that the provisions of s 733 of the LGA do not apply because the ponding complained of by the plaintiff is not "flooding" but a failure of the defendant's stormwater drainage system to cater for relatively small regular stormwater runoff events. It was submitted that s 733(4) and (5) refer to a manual relating to the management of flood liable land. The NSW Floodplain Development Manual was first released in 1986 and gazetted in 1987. The next version was issued and gazetted in April 2005. The plaintiff submitted that it is significant that the defendant does not allege that the drainage problems that are the subject of these proceedings fall within the scope of either version of that manual. The plaintiff contended that this is because the drainage problems are local drainage problems that fall outside its scope. The plaintiff also submitted that to the extent that the acts and omissions of the defendant relate to water quality as opposed to flooding, the section has no application. 410The plaintiff submitted that the defendant has not established that it acted in good faith in relation to the nuisances. It contended that the defendant acted contrary to its stormwater and flooding protection policies and also permitted NPE to breach them. It imposed Q5 and Q100 conditions of consent on NPE and approved the sub-divisions without the drainage works required by those conditions, knowing of those breaches. It permitted the blocking and subsequent filling of the Northern Drain despite its experience with local drainage problems during the development of NPE and despite the fact that it had previously permitted the blocking and filling in of the Natural Watercourse. 411The plaintiff submitted that when the defendant became aware of the drainage problems resulting from the filling in of the Northern Drain and NPE's refusal to replace it with a Q100 flow path, it adopted the strategy put forward by Mr Findlater despite the fact that he had a clear conflict of interest and in circumstances where the plaintiff was to bear the costs and damages burden of either accepting stormwater or apparently gifting its land to the defendant for a retention basin without the informed consent or knowledge of the reason for the increased flow being the breach by NPE and its agent Mr Findlater. 412The plaintiff submitted that the defendant met and corresponded with the plaintiff and its agents on numerous occasions about drainage issues on the Land, agreed to the plaintiff undertaking the drainage study, and later requested the plaintiff fund the bulk of the WBM drainage study. It was submitted that at no stage did the defendant inform the plaintiff that the drainage problems on the Land were the result of the filling of the Northern Drain and its replacement by the inadequate 1200mm pipe. The defendant did not invite the plaintiff to participate in working groups directed at resolving the Kingscliff drainage issues. Rather the plaintiff proposed that a working group be established when it was informed by the defendant that a large retention basin would be required on the Land. The plaintiff was not advised as to why such retention basin was required. Although there is the ubiquitous mention from 1995 onwards of the need for amendment to DCP 9, this has not occurred. 413The plaintiff also submitted that the defendant caused Turnock Street and Elrond Drive to be designed and constructed with all but one of the culverts above ground level and with no table drain, in breach of its policies for drainage under public roads and despite the fact that it was aware of the increased stormwater flows coming onto the Land. The plaintiff submitted that in those circumstances the defendant had not established that it acted in "good faith" within the meaning of that expression in s 733 of the LGA. 414The defendant's conduct in retaining Mr Findlater in the first place when he was the representative of NPE, the party in breach of the conditions of development consent, is quite extraordinary. But to accept his recommendation that the plaintiff should be the party to bear the burden of the consequences of NPE's breach is even worse. To accept it and impose it on the plaintiff without advising the plaintiff of the reason for its imposition and without offering any form of relief or compensation to the plaintiff is extremely high handed and could not be described as acting in good faith. The defendant failed to disclose the reason for its decision to utilise the Land as a retention basin when it entered into the agreement to purchase part of the Land and construct Turnock Street. It was not until the plaintiff's representatives had access to the defendant's files that the plaintiff became aware that the Northern Drain had been filled by NPE in breach of the conditions of its development consent. 415Assuming that the section applies I am not satisfied that the defendant's conduct in imposing the retention basin on the plaintiff was done in "good faith". 416The defendant's conduct after the nuisance was bought to its attention in 2004 was in my view also lacking in good faith. The plaintiff approached the defendant in a conciliatory fashion to see if they might find a "solution" together. Rather than accept this approach the defendant called for a public apology and payment of large amounts of costs at a time when the defendant was still using the plaintiff's Land as a retention basis at no cost to the defendant. It is hardly conduct that could be described as in good faith. 417The defendant does not have the protection of the provisions of s 733 of the LGA in all the circumstances. Damages 418The plaintiff makes a number of claims in respect of the relief sought to abate the nuisance including a mandatory injunction requiring the defendant to complete the Blue Jay Circuit Scheme. However in the alternative the plaintiff seeks an award of damages in the amount of $600,000 to compensate it for the need to install a drainage system across the Land to accommodate the additional stormwater on the Land. The plaintiff also claims damages in respect of the loss of the value of the Land that has to be quarantined to protect the Wallum Froglet habitat. A further claim is made for the additional cost and expense of maintaining the Wallum Froglet habitat by reason of the requirement to treat the untreated stormwater to make it suitable for the Wallum Froglet habitat. The plaintiff also makes a claim for the additional cost that will be incurred in relation to the fill that it will have to provide by reason of the presence of the untreated stormwater on its Land. There is also a claim for the cost incurred in obtaining expert assistance in 2004 in relation to the establishment of the table drain and for the costs of and associated with the construction of the table drain. The plaintiff also seeks injunctive relief to rectify the problems in relation to the Quigan Street outlets. Blue Jay Circuit Scheme 419The defendant has resisted this relief on the basis that it is premature to complete the works until the plaintiff has indicated the nature of the proposed development of the Land and that it will proceed with its development. There is no doubt that the plaintiff's establishment of the table drain in 2004 has reduced the problems that arose with the ponding of water north of Turnock Street. I have found that the table drain has abated the nuisance except after major storm events. The drainage system in respect of the Land is still inadequate after major storm events and it is necessary to find a way in which the plaintiff can be relieved of the burden that has been imposed upon it by reason of the inadequate drainage system and the use of its Land as a retention basin. 420The nuisance after major storm events will continue unabated unless steps are taken to rectify the problem. It is accepted that the drainage problems that have caused the nuisance on the Land will be solved by the construction of the Blue Jay Circuit Scheme. However that process involves obligations to and of third parties who are not parties to this litigation. Although it may be convenient to describe the project in a short hand way as the "Blue Jay Circuit Scheme", it is a complex process of road and drainage construction that will affect a number of third parties. There are also the vagaries of development and construction with the consequent uncertainties, both temporal and more substantive. If it were the subject of a mandatory injunction of this Court it would require supervision. This would be a most unsatisfactory outcome. 421The question arises as to whether damages are an adequate remedy in the circumstances: Bankstown City Council v Alamdo Holdings Pty Limited at 665 [11]. I am satisfied that damages are an adequate remedy. The plaintiff's alternative claim for $600,000 is based on an agreed figure adopted by Philip Barlow and Kent Wood, valuers (Ex PD 10) that will enable the plaintiff to install a drainage system on the Land that will abate the nuisance. This figure is made up of $571,000 plus an allowance for interest. I am satisfied that this is the appropriate relief rather than the mandatory injunction. Loss of value of the Land for Wallum Froglet habitat 422The increase in the number of the Wallum Froglets on the Land was recorded in Mr Parker's Report in April and May 2003. I have found that there was a viable population of Wallum Froglets on the Land in late 2002/early 2003. This occurred before 5 March 2003 when the plaintiff advised the defendant that it was no longer willing to tolerate the discharge of the stormwater runoff onto the Land and before 4 May 2004 when the plaintiff advised the defendant that there was an unreasonable interference with the enjoyment of its Land. Although all of the physical features that were present at 4 May 2004 were present prior to that time, the plaintiff tolerated those physical features without demur as to its enjoyment of the Land and thus there was no actionable nuisance prior to that time. 423The plaintiff cannot complain that the presence of the viable population of Wallum Froglets was a consequence of the actionable nuisance. It may well have been a consequence of the conduct of the defendant prior to 2004 but the nuisance action did not arise until there was the unreasonable interference with the plaintiff's enjoyment of the Land. As I have already said, the action in negligence that concerned the events prior to this time was abandoned on the seventh day of the trial. 424I am satisfied that because there was a viable population of Wallum Froglets on the Land prior to the time of the first nuisance, the plaintiff is unable to recover damages for the exclusion of that part of the Land from its development that is to be preserved for the Wallum Froglet habitat. 425Although in the circumstances of this finding it is unnecessary, I will shortly address the foreseeability arguments that were raised by the parties. The defendant submitted that the plaintiff's claim that it should have had the risk of the invasion of any endangered species in mind in the course of its activities raises the spectre of an obligation to have in mind the "risk" of preserving a bewildering array of potential invaders and presumably of promoting a wide range of habitat requirements. The defendant posed the question of whether in the circumstances it is required to balance in its mind whether to preserve a wet environment conducive to frog survival or create a dry environment for the survival of the threatened Mitchell's Rainforest Snail. The complexity of the problem is illustrated by the consideration of the species identified in the fauna and flora studies prepared in connection with the Land. In the 1994 Warren survey the threatened species included a broad range of "Avifauna", "Mammals" and "Amphibians" recorded in the localities. Endangered fauna possibly occurring on the Land included the osprey, white-eared monarch, black-necked stork, black flying fox, and the Queensland blossom bat. The 1996 Woodward-Clyde survey identified many different threatened faunal species on or near the Land. 426The complexity is exacerbated by the differing opinions that were provided to the parties during the 1990s. Mr Warren expressed the view in 1994 that it was possible though unlikely that the Land contained Wallum Froglets. He expressed the view that if they were to be on the Land it would be most likely that they would be found in the "wet areas associated with the Paperbark forests". In 1996 Mr Warren said that they were most likely to occur "along the drain to the south of the roundabout where a number of other frogs were recorded". In 1999 he expressed the view that they would be restricted to the "small areas" of low-lying Paperbark vegetation in Lot 13 and in the Paperbark swamp to the south of the Land. 427I do not accept that the prospect of the invasion of a colony of Wallum Froglets should have been in the mind of the defendant when it authorised the NPE development or when it decided to utilise the plaintiff's Land as a retention basin for the stormwater run-off of the area. The amount of research that has been carried out on the Land over the years would not have alerted either party to the prospect of the invasion of the colony of Wallum Froglets. The research identified a single call of the Wallum Froglet in 1998, two years after the construction of Turnock Street, at a time when there was an anticipation that the plaintiff would fill its Land in the not too distant future. 428The defendant did give consideration to whether there were Wallum Froglets present on the Land that might be harmed by the proposed development and the construction of Turnock Street. There is no doubt that those investigations suggested that there was no Froglet population of any significance in that area. The defendants submitted that in those circumstances it would be manifestly unreasonable to suggest that a reasonable Council would have been alert to the risk that the development might serve to alter that position. 429I accept that the defendant anticipated that the plaintiff would seek to develop the Land sooner rather than later. I accept that this anticipation was the reason it constructed Turnock Street with the culverts approximately halfway up the embankment to accommodate the Land as filled. If the plaintiff is correct in its submissions that the risk was foreseeable, the defendant would have had to anticipate that the plaintiff would delay by a measure of years its filling of the Land, that the increase in stormwater run-off onto the Land would not only be impeded by the absence of the culverts at ground level but would also be impeded to the extent that ephemeral ponding would not only occur but would remain for necessary periods of five to six weeks in summer and/or some months in winter. I do not accept that the risk was reasonably foreseeable in all the circumstances of this case. It was remote. Cost of treating water for the Wallum Froglet habitat 430The plaintiff submitted that the defendant must take the plaintiff as it finds it, with the Wallum Froglet habitat and with its legal obligation to protect it: Roberts v Rodier (2006) 12 BPR 23,453; [2006] NSWSC 282 at 23,477. At the time the defendant was put on notice that the plaintiff's enjoyment of the Land was being unreasonably interfered with it knew that there was a viable population of Wallum Froglets on the Land. The risk that the plaintiff would be put to additional cost and expense in treating or improving the quality of the untreated stormwater so as to accommodate the Wallum Froglet was foreseeable but the defendant has done nothing to alleviate or eliminate the flow of the untreated stormwater onto the Land. 431It is clear that the Wallum Froglet population has declined and indeed it could disappear from the Land. There is the prospect that the Blue Jay Circuit Scheme will be completed when the contribution is received from the Nursing Association. The timing of that contribution is uncertain. It is also possible (although it would be hoped not probable) that the defendant may revisit its decision and not proceed with the Blue Jay Circuit Scheme. There is the complicating factor of the timing of the completion of any drainage works the plaintiff undertakes to remove the stormwater from its Land. As this process will have to be undertaken in consultation with and approved by the defendant delay may well occur (having regard to the previous history between these parties). 432The plaintiff is entitled to recover any additional costs of treating the stormwater that are incurred prior to the completion of its drainage works or the completion of Blue Jay Circuit Scheme. It is necessary to take into account the fact that the plaintiff would have to treat the water irrespective of the stormwater on the Land caused by the nuisance. I am satisfied that the appropriate way to deal with this is to allocate a percentage of those costs. This cannot be done with any mathematical or scientific precision and in the circumstances of the evidence, particularly since the installation of the table drains in 2004, I am satisfied that the appropriate allocation is 30% of those costs up to the completion of the plaintiff's drainage works or the Blue Jay Circuit whichever is the earlier. These costs will need to be assessed in due course. Costs of the fill 433The plaintiff also made a claim for the additional costs that will be incurred by reason of the type of fill that will be required for the development of the Land that is caused by the presence of the additional stormwater on the Land. In the light of the order to be made for the award of damages for the plaintiff's drainage works with the consequence that the nuisance will be abated I do not intend to make an award of damages for this claim. Costs in relation to table drain 434The plaintiff retained experts, including Dr Webb, to assist it to find an appropriate mechanism to abate the nuisance. This resulted in the construction of the table drain. As I have already said this resulted in more efficient and effective drainage of the Land, so that the nuisance only occurs after major storm events. I am satisfied that the plaintiff is entitled to recover the costs of retaining the experts and the costs of and associated with the construction of the table drain. Quigan Street Outlets 435There was a question raised during the proceedings as to whether the plaintiff had properly pleaded its claim in respect of the Quigan Street outlets. Although that submission may have had some force I was of the view that the evidence in relation to those outlets was relevant and that the plaintiff should be allowed to proceed with its claim for injunctive relief in relation to the Quigan Street outlets. 436After the plaintiff opened its case I indicated to the defendant that the problem with one of the Quigan Street outlets required attention. The defendant indicated that its officers wished to attend to repair the concrete apron on the side of that outlet (tr 424). It is not clear whether any rectification or repair work has been done. The plaintiff seeks orders that the defendant install pollutant traps and energy dissipation structures. I am satisfied that such work should be completed. Unfortunately there has been disagreement as to what steps should be taken in this regard mainly, I apprehend, because the defendant has not regarded itself as liable for the cost of completing the works. 437I am satisfied that the gross pollutant traps and energy dissipation structures should be installed. I will either award the plaintiff damages to compensate it for the costs of the installation or alternatively the defendant can agree to a regime of installation of the gross pollutant traps and energy dissipation structures. I will hear the parties on the orders to be made to effect this result. Conclusion 438The plaintiff's claim for the mandatory injunction in respect of the completion of the Blue Jay Circuit Scheme will be dismissed. The plaintiff is entitled to an award of damages in the amount of $600,000 on the basis that it will install a drainage system on the Land to divert the additional stormwater from the Land. 439The plaintiff is not entitled to recover damages for the loss of the value of the Land to be used for the Wallum Froglet habitat. The plaintiff is not entitled to recover the costs as claimed for the fill for the Land. 440Should the plaintiff be required to continue to maintain the Wallum Froglet habitat, it is entitled to recover 30% of any costs of treating the stormwater to make it suitable for the Wallum Froglet habitat up to the date of completion of its drainage works on the Land or the date of the completion of the Blue Jay Circuit Scheme, whichever is the earlier. Those damages will be assessed in due course. 441The plaintiff is also entitled to damages for the costs of the expert advice and assistance in respect of the table drain installed on the Land in 2004 and of the costs of and associated with the construction of that table drain. Those damages are to be agreed and if not agreed they will need to be assessed. 442Gross pollutant traps and energy dissipation structures are to be installed in the Quigan Street outlets. I will hear the parties on the orders to be made to effect this result. 443The matter will be listed for the filing of Short Minutes of Order to reflect these findings together with any agreed costs orders. If the parties are unable to agree on those orders I will list the matter for argument on a date to be arranged with my Associate. The parties should make contact with my Associate with the agreed date for that listing by no later than 20 October 2011. *************** SCHEDULE A SCHEDULE B DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated. Decision last updated: 21 September 2011