New South Wales District Court CITATION: Andrew Walsh v Adam Ginsberg [2010] NSWDC 164 HEARING DATE(S): 01/02/10 - 05/02/10, 3/5/10 - 06/05/10, 23/07/10, 30/7/10 JUDGMENT DATE: 30 July 2010 JURISDICTION: Civil JUDGMENT OF: Rolfe DCJ DECISION: Verdict and Judgment for the Defendant CATCHWORDS: Action in Nuisance - Categories of Private Nuisance - Principles applicable to nuisance created by surface water - Considerations of reasonableness and compromise - Necessity for there to be material damage - Application to the facts Hunter v Canary Wharf Limited & London Docklands Development Corporation (1997) 2All ER 426 Gartner v Kidman (1962) 108 CLR 12 Corbett v Pallas (1995) 86 LGERA 312 CASES CITED: Sedleigh-Denfield v O'Callaghan (1940) AC 80 Bayliss v Lea (1961) NSWR 1002 St Helens Smelting Company v Tipping (1865) 11 ER 1483 Bonnici v Ku-Ring-Gai Municipal Council (2001) NSW SC 1124 TEXTS CITED: Fleming on Torts 2nd Ed PARTIES: Andrew Walsh (Plaintiff) Adam Ginsberg (Defendant) FILE NUMBER(S): 921/09 COUNSEL: M Hadley (Plaintiff) M Luitingh (Defendant) JUDGMENT 1 The plaintiff and defendant are young men who live with their wives and families in adjoining properties located in a bushland setting close to one of Sydney's northern beaches. For the sake of the parties' privacy, I will refer in this judgment to the street in which they both live as "the Road". The Road can be seen in the location maps, being exhibit J. 2 The plaintiff and his wife and children live at number 24 and the defendant and his wife and children live next door at number 26. Exhibit H is a helpful aerial photograph of the two properties. 3 The neighbourhood is nowadays a densely populated urban area with properties close to each other. Both number 24 and number 26 are downhill from the top of Bushrangers Hill (the "Hill"). The evidence shows that water has always flowed down from the top of the Hill, sometimes in considerable volumes, onto the properties now owned by both the plaintiff and the defendant. 4 The plaintiff purchased number 24 in 2002. At or around the same time, his parents purchased number 22 and they still live there. 5 Shortly after purchasing his property, the plaintiff and his family built a new home on it which they completed in December 2004. 6 The defendant purchased number 26 in November 2003. He rented the property for a short time to the previous owner before he and his family commenced living there in 2004. 7 When he purchased it, the defendant's property was an old two-storey, mostly weatherboard, home which had been constructed some time in the late 1930's or thereabouts. Unlike the plaintiff, the defendant did not demolish the home but, instead, he renovated and refurbished it. Construction work began on number 26 in early 2008. The work is not fully complete. 8 The Road runs along the southern boundary of both properties. Approaching it from the closest main street, the Road runs in an approximately east-west direction. Number 26 is located to the east of number 24 and is effectively in the shape of a rectangle the longer sides of which run south-north looking towards the beach. 9 The entire western boundary of number 26 borders number 24. 10 The northern boundary of number 26 adjoins the boundary of number 24 for about half way along. The remaining half, that is the eastern side, adjoins the property of Mr Wilson. 11 There is a separate boundary to the north of number 24 which runs from south to north between number 24 and the property owned by Mr Wilson. 12 It is common ground that the dominant slope is from the street frontage of each property (south) to slightly west of north. In layman's terms, this is a dominant south-north slope with an east-west tilt and it causes surface water to fall slightly westwards as well as northwards. 13 In these proceedings the plaintiff alleges that prior to 2008, at the northern end of number 26, there was a grassed yard in front of the old house. By reason of the contours of the land, some rainwater which fell onto that yard always flowed onto the plaintiff's land. However, the plaintiff says that the only rainwater which flowed onto his property from the defendant's yard was rainwater which had not soaked into the ground on number 26 or had not flowed on to Mr Wilson's property or elsewhere. 14 In a nutshell, the plaintiff's complaint is that the extensions and renovations which have been carried out on number 26 have materially altered and increased in volume and concentration the natural flows and drainage of water onto number 24 and he has suffered damage as a consequence. In this respect, the plaintiff accepts that the steps taken by the defendant did not arise from any ill will towards the plaintiff (Plaintiff's counsel's submissions, para 10). 15 The defendant's extensions include a dispersion trench excavated along the northern boundary of that part of number 26 which is shared with number 24. The plaintiff alleges that the dispersion trench slopes with increasing depth from east to west. It is partially filled with stones and gravel. 16 The plaintiff alleges that part of the work done at number 26 included drainage pipes. These pipes divert a substantial amount of rainwater into the dispersion trench. 17 The ingress of stormwater flowing from the defendant's property onto the plaintiff's property is in the location where the two properties abut one another which the parties described in the evidence as the "north western boundary" (NWB). At this point the defendant's property is upslope from the plaintiff's property. 18 It is common ground that on the plaintiff's side of the NWB there is a "flattish area" which the parties described in the evidence as the childrens' cubby area. The childrens' cubby area is approximately 3% of the plaintiff's land mass. The typography of the childrens' cubby area generally ranges from a 15 degree down slope to a 40 degree down slope. The plaintiff artificially constructed and levelled the land in this area. Soil tests confirm this, as Mr Theunissen's evidence at paragraph 118 of his affidavit discloses (exhibit 6). 19 There is evidence that water pools on the flattish part of the childrens' cubby area from time to time. Although contentious, there is evidence that this occurred before the plaintiff and the defendant purchased and took possession of their properties. It is important to note that in the process of constructing the childrens' cubby area, the plaintiff raised it so as to prevent the flow of water downhill on his land on the natural levels of the typography. For his part, on his side of the NWB, the defendant constructed the dispersion trench. This was part of a stormwater management system designed to control the natural flow of water that the defendant says has always flowed onto the plaintiff's property. 20 The plaintiff alleges that as a consequence of the defendant's actions the following has occurred: (a) The grass area in the childrens' cubby area has become sodden and water and silt have washed onto his land during rainfall events. (b) Loss of amenity of the childrens' cubby area after rain events. (c) Water damage to trees. (d) Water damage to dry stacked walls. (e) Infestation of mosquitoes. (f) Reasonable apprehension of landslip. 21 The plaintiff therefore says the defendant's actions are an unreasonable interference with the plaintiff's use and enjoyment of his land and as such are an actionable nuisance. 22 The plaintiff also says that by reason of the adjoining nature of the properties the defendant owed the plaintiff a duty of care in relation to any changes made to number 26 which could have reasonably foreseeable detrimental effects to the plaintiff's land at number 24. In this respect, the plaintiff alleges that it was reasonably foreseeable that the excavation of the dispersion trench and the diversion of substantial quantities of water into it would cause discharges of water onto number 24 and into the sub-soil of number 24 below the surface. It is also alleged that it was reasonably foreseeable that the excavation of the dispersion trench and the diversion of substantial quantities of water into it would increase the propensity for landslip on the defendant's property. However, counsel for the plaintiff accepted that, if the plaintiff's claim in nuisance did not succeed, neither would the claim in negligence. 23 The plaintiff alleges the defendant constructed the dispersion trench and the drains leading to it without any competent advice and without any reasonable basis for believing that the plaintiff's land would not be affected to an unreasonable extent and the defendant was thereby negligent in constructing the trench and the drains leading to it. 24 The plaintiff claims that as a result of the matters referred to he has suffered the damage identified in paragraph 20. 25 The plaintiff says that despite numerous complaints the defendant has refused to remove or abate the nuisance and to deal with the consequences of his alleged negligence. All of these matters are said to continue into the future. In the plaintiff's Statement of Claim, therefore, he asks the Court to grant injunctive relief. 26 Although the court urged the parties to endeavour to resolve the matter, unfortunately they were unable to do so. This is regrettable, considering that both parties and their families were friends before this dispute occurred and, importantly, they remain neighbours. 27 The Court has been considerably assisted in its determination of this dispute by written submissions of the plaintiff's counsel dated 24 May 2010 (in chief), further submissions received 18 June 2010 (in reply) and written submissions of the defendant's counsel (in chief) dated 7 June 2010. 28 In response to the plaintiff's allegations, the defendant says that the works he had carried out at number 26 did not materially alter the natural flows of rainwater onto number 24. He also says that the work carried out during the course of his renovations, which included the installation of a stormwater drainage and management system, constituted a natural and reasonable use of the defendant's land. The defendant therefore says he took reasonable precautions to prevent any increase in the flow or percolation of rainwater from number 26 onto number 24. 29 Generally speaking, there are three categories of private nuisance. First, by encroachment on a neighbour's land; secondly, by direct physical injury to the neighbour's land; thirdly, by interference with the neighbour's quiet enjoyment of his land: Hunter v Canary Wharf Limited & London Docklands Development Corporation (1997) 2All ER 426. 30 Broadly speaking, the plaintiff's claim falls within the second and third categories. 31 In relation to nuisance created by water, the leading case in Australia remains Gartner v Kidman (1962) 108 CLR 12. Although the facts were different from the present case, Windeyer J at para 48 set out what he and Dixon CJ considered were the principles that apply to an action in nuisance created by surface water (essentially, McTiernan J concurred). 32 First, surface waters are those which come naturally upon the land from which it flows. These waters are distinct from waters which are artificially brought or concentrated on the land and allowed to escape. With this in mind, Windeyer, J stated that the rights and obligations of the proprietors of contiguous closes, one on a higher level than the other, are as follows: (a) The higher proprietor is not liable merely because surface water flows naturally from his land on to lower land. (b) He may be liable if such water is caused to flow in a more concentrated form than it naturally would. (c) Surface water flows in a more concentrated form than it naturally would if, by the discernible work of man, the levels or conformations of land have been altered, and as a result the flow of surface water is increased at any particular point. (d) If a more concentrated flow occurs simply as the result of the "natural" use of his land by the higher proprietor, he is, generally speaking, not liable. What is a natural use is a question to be determined reasonably having regard to all the circumstances, including the purposes for which the land is being used and the manner in which the flow of water was increased: as for example whether it is agricultural land drained in the ordinary course of agriculture, whether it is timbered land cleared for grazing, whether it is a mining tenement, or is used for buildings and so forth. (e) The proprietor of higher land is not liable for a more concentrated flow from his land if it is the result of work done outside his land by someone else, and for the doing of which he is not responsible, as for example by the paving and guttering of public roads by municipal authorities. (f) The above statements relate to cases where the higher land and the lower land are held by separate proprietors. Different considerations apply when the lower land receives a concentrated flow as the result of work which was done when it and the higher land were in the same ownership and possession. (g) The lower proprietor may recover damages from, or in appropriate cases obtain an injunction against, the proprietor of the higher land who is, for any of the reasons given above, liable to an action because he has concentrated or altered the natural flow. 33 The plaintiff says that on the evidence of its lay witnesses and experts, the case falls squarely within the principles set out above in favour of the plaintiff because: (a) The flow from number 26 to number 24 is now more concentrated than it naturally was before the defendant carried out the work on number 26. (b) The concentration has been caused by the works carried out by the defendant. (c) The evidence supports a finding that the change in concentration has occurred at a particular point on number 24 and this is sufficient to establish the plaintiff's case. (d) Nothing the defendant has done which might amount to a more concentrated flow is the result of the natural use of the defendant's land. 34 In approaching these matters, I have had regard to what was said by the Court of Appeal in Corbett v Pallas (1995) 86 LGERA 312 based on their Honours understanding of the principles in Gartner v Kidman: (i) To establish a prima facie case it is sufficient for the plaintiff to prove that material damage to his property has resulted from an increase in the flow, or percolation, of surface water due to the defendant's act in altering the conformation of land in the course of the defendant's use of it. (ii) The plaintiff does not have to prove unnatural or unreasonable use of the land by the defendant. (iii) If the conformation of the land is altered in the course of some specific use that may avoid liability, the burden of proof is on the defendant to establish it as a distinct defence. (iv) Unreasonable use is not an ingredient of the cause of action, but certain types of use may amount to a "natural" and reasonable use of the land and provide a defence. (v) Whether a particular use of land is "natural" must be determined reasonably having regard to all the circumstances, including the purpose for which the land is being used and the manner in which the flow of water is increased. 35 The defendant contends that the plaintiff has conducted himself unreasonably but accepts that the onus to prove this rests on the defendant. The defendant also contends that he has made reasonable and proper use of his property and accepts he has the onus of proving that. 36 It is also useful to bear in mind what has been said in some of the other cases. In Sedleigh-Denfield v O'Callaghan (1940) AC 80 at 893 Lord Wright said: "A balance has to be maintained between the right of the occupier to do what he likes with his own, and the right of the neighbour not to be interfered with. It is impossible to give any precise or universal formula, but it may broadly be said that a useful test is perhaps what is reasonable according to the ordinary usages of mankind living in society." 37 In Bayliss v Lea (1961) NSWR 1002, the Full Court of the Supreme Court of New South Wales said the Court's task was to reconcile the conflicting aims of adjoining landowners by effecting a compromise. The Full Court approved the following statement by Fleming on Torts 2nd Ed p 400-1: "The paramount problem in the law of nuisance is, therefore, to strike a tolerable balance between conflicting claims of landowners each of whom is claiming the privilege to exploit the resources and enjoy the ameníties of his property without undue subordination to the reciprocal ínterests of the other. Reconciliation has to be achieved by compromise, and the basis for that adjustment is reasonable user. Legal intervention is warranted only when an excessive use of property causes inconvenience beyond what other occupíers in the vicinity can be expected to bear, considering the prevailing standard of comfort of the time and place. Reasonableness in this context is a two-sided affair. It is viewed not only from the standpoint of the Defendant's convenience, but must equally take into account the interest of the surroundíng occupiers. It is not enough to ask: Is the Defendant using his property in what would be a reasonable manner if he had no neighbour? The question is: Is he using it reasonably, having regard to the fact that he has a neíghbour?" 38 In terms of material damage, the law does not regard trifling and small inconveniences or interferences as sufficient. To be actionable, the injuries must diminish the comfort, enjoyment or value of the property which is affected: St Helens Smelting Company v Tipping (1865) 11 ER 1483. 39 The matter of damage has to be approached objectively having regard to the reactions of normal persons in the locality and not a particular plaintiff's idiosyncrasies: Bonnici v Ku-Ring-Gai Municipal Council (2001) NSW SC 1124. This is particularly apposite in this case. 40 In seeking to prove his case the plaintiff has relied on the following: (a) Testimony of lay witnesses but particularly his and that of his gardener; (b) Photographs and videos; (c) The history of complaints the plaintiff made (see annexure 'A' to the plaintiff's counsel's submissions in reply). (d) Expert evidence of Mr Crozier and Mr McGeady. (e) An inference which the plaintiff says can be drawn by looking at both properties and considering a "before" and "after" situation as a result of the work done by the defendant. 41 In resisting the plaintiff's claims the defendant relies on his own evidence as well as that of the previous owner. The defendant also relies on expert evidence to support the following contentions: (a) That he has decreased the flow and concentration of water flow over the boundary: Expert Report of Mark Tooker, exhibit 6 page 11; Expert Report of Michael Kelett, exhibit 6, page 3, para (iv). (b) That he has used his property reasonably to implement, in the circumstances, the only reasonable and practicable stormwater management system in the only place possible on his property: Affidavit of Woodie Theunissen of 9 November 2009, exhibit 6, paragraphs 24; 25; 29. (c) The plaintiff has failed to take any reasonable steps to control stormwater runoff from the plaintiff's property as recommended by Douglas & Partners: exhibit 1, Tab 3; pp 37-40; T D3 p51. (d) The plaintiff has refused to grant the defendant an easement when he could and should have done so. (e) By constructing a retaining wall on the north-south boundary between number 24 and number 26 the plaintiff has diverted stormwater to the NWB. (f) There is no reasonable apprehension of landslip: Expert Report of Woodie Theunissen, exhibit 6; Issues for Expert Determination, exhibit M p2; Expert Conclave, exhibit 5. 42 I will now consider the facts. 43 When the defendant purchased the old house at number 26 it had a pitched roof which was drained by guttering that fed downpipes at each corner. There was a sundeck on the northern end of the house with its own small roof that was drained by two downpipes. In this respect I will follow the labelling suggested by the plaintiff's counsel in his submissions where R = roof and S = sundeck, so that the six downpipes can be described as: RSE RNE SNE RSW RNW SNW 44 The two southern pipes were independent of the four northern pipes. 45 The four northern downpipes (SNE, SNW, RNE & RNW) discharged into a single terracotta pipe which went into the ground close to the bottom of RNW. It seems everyone assumed this piping continued underground and downhill through other properties until it reached a council drain some distance below in another street. Therefore, the initial drainage arrangements for the defendant's proposed extensions were planned on this basis. However, once the works on number 26 got under way, the builder discovered that the terracotta drainage pipe on number 26 was not in any way connected to another system leading to a council drain further down the hill. 46 There is no definitive evidence about RSE and RSW but it appears that a few underground terracotta pipes were used as well so that rainwater could disperse into the ground under the house. The plaintiff accepted that any backed up water "would flow out over the ground and towards the northern boundary with also some westward tendency" (Plaintiff's counsel's submissions para 27). 47 In terms of background only , it is useful to note that number 26 was built a long time ago. It was not long after the Sydney Harbour Bridge had been opened. Sydney's population was only just starting to expand on the upper north shore. So, at the time number 26 was built, the suburb would have been sparsely populated and there were probably not many houses. Indeed, the Pittwater Council Library Service local study on the suburb, which can be downloaded on Google, suggests that in the 1930's the suburb was still largely made up of holiday homes with many houses empty for much of the year. It was not until the 1950's that the area truly became a residential suburb. 48 It is hardly surprising therefore that someone (probably the original builder of the old number 26) opted for the rough and ready solution of attaching several lengths of terracotta pipe which came to an end under the ground on number 26 on the assumption that surface water would naturally drain downhill in the ordinary course. This meant that, when rainfall was significant, there was a backup of water which created a pressure head on the first joint of the downpipe above ground level causing water to flow out from there as well. The plaintiff accepted that such backup water would flow out over the ground and "towards the (defendant's ) northern boundary with also some westward tendency" (Plaintiff's counsel's submissions para 27). 49 The plaintiff and the defendant did not find out about this rough and ready solution until June 2008. The background to that discovery is as follows. 50 In March 2004 the defendant retained Jeffery and Katauskis Pty Limited ("J&K") to prepare a geotechnical assessment report in order to assess the existing slope stability of the site at number 26 and the effect on stability on his proposed development. The report is annexure A to the affidavit of 9 November 2009 of Mr Walker of J & K (exhibit 12). 51 The geotechnical assessment report was required for number 26 in accordance with Pittwater Council's Geotechnical Risk Management Policy, which had been adopted on 17 June 2003. Properties identified on the Geotechnical Hazard Mapping of Pittwater Area required a geotechnical assessment to be completed by a qualified geotechnical engineer to identify geotechnical risks, assess the magnitude of the identified risks and recommend measures to reduce those identified risks that are reasonable and practical (Mr Theunissen's affidavit, pg 3, para 6). It is common ground between the parties that both number 26 and number 24 are zoned H1, the highest level of potential hazard (T D8 p 205 line 40). 52 At Section 5.2 (pg 10) of the J & K Report they identified certain potential landslide hazards as follows: "100.1 A(i) stability of existing sandstone walls supporting the landscaped gardens between the road and the house, on the eastern and west sides of the site, and the grassed terrace in the neighbouring property to the northwest; 100.2 A(ii) stability of existing sandstone retaining walls, one supporting the grassed terrace adjacent to the southwest side of the house, and two to the east of its northwest corner; 100.3 E stability of slope adjacent to the north side of the house and below the deck; and 100.4 G stability of hillside slopes to east and west of the house. 53 As can be seen from the identification of hazard A(i) above, consideration was given by J & K to hazards existing on the plaintiff's property in relation to the potential works to be carried out on the defendant's property. 54 As is clear from Mr Theunissen's evidence, the identification of a potential hazard does not equate to the risk of that hazard occurring. The risk of each of the hazards described above was assessed by J & K in their report as "low" to "very low". Such risks were therefore within the "Acceptable" level required by Pittwater Council. 55 Mr Theunissen directed all the subsurface testing which was necessary for the preparation of the J & K report. This included penetrometer testing and the results are annexed to the J & K report. 56 J & K prepared their report on the basis that the existing stormwater system went safely underground downhill from number 26. At the time, this was also the understanding of Mr McGeady, the hydraulic engineer who had designed the stormwater management system which had already been installed in the plaintiff's property. 57 On the basis of this incorrect assumption, J & K said in their report: "6.1.7 A cut off surface drain should be installed along the uphill side of the site. This drain, which will divert surface water runoff, should be connected to the stormwater system. The drain should be lined or sealed to reduce the infiltration into the subsoils and should also be provided with generous slopes. 6.1.8 The surface water discharging from the roof and paved areas must be diverted to outlets for controlled discharge to the existing stormwater system which appears to drain into the neighbouring property to the north." 58 The proposed arrangement was depicted in drawing D01: see Mr Kelett's affidavit of 6 November 2009, annexure E (exhibit 6). Mr Kelett is the principal of MtK Consulting, Structural, Civil & Stormwater Engineers ("MtK"). MtK was engaged by the defendant on 28 November 2007 to provide hydraulic engineering services in connection with number 26. Mr Kelett's role was to fulfil the requirements of the Private Certifying Authority regarding stormwater so the defendant could obtain a construction certificate. MtK also had to ensure that the recommendations made by J & K were followed. They included preparation of drawings for review by J & K. 59 After carrying out an inspection of number 26 on 4 December 2007, Mr Kelett advised the defendant to replace the existing stormwater pipes because his examination of the aboveground ones revealed they were in a poor state. The defendant accepted this recommendation. Because he was recommending that all stormwater pipes be replaced, Mr Kelett did not observe the southern downpipes at the time of his inspection on 4 December 2007. This explains why, at the time of preparing this report of 6 November 2009, Mr Kelett assumed that the stormwater from the southern downpipes was piped to the north and joined the water from the northern downpipes. (T D9, p 275.25). 60 Mr Kelett said in his evidence in chief that when he first looked at the survey plan of number 26, it indicated there was a cross-fall on that property from the south to the north and also from east to west. When he inspected the site on 4 December 2007, Mr Kelett's observation enabled him to confirm that this was correct. So Mr Kelett concluded that, as things stood, overland stormwater flowed from number 26 to the NWB. 61 Mr Kelett then prepared stormwater plans for number 26. In doing so he assumed that the existing stormwater management system on number 26 discharged to a soaker trench or dispersion trench on the site below the residence towards the northern boundary, that is, in the area of the defendant's yard. Mr Kelett prepared initial plans dated 24 January 2008 and Revision A plans dated 14 February 2008. The Revision A plans were approved by J & K. The Revision A plans provided for all stormwater from the defendant's roof to be piped to two proposed re-use tanks (or bladders) and from there to connect to the existing stormwater system. 62 Mr Kelett has done a lot of work in this area of Sydney. His experience is that the majority of older residential properties on the low side of a street discharged stormwater from a pipe system into a soaker trench or dispersion trench within a rear yard. That formed the basis of the assumption he made in preparing his stormwater plans for number 26. 63 On 18 June 2008 Mr Kelett was called to a site meeting at number 26 by the defendant. He was informed that the builder had uncovered the discharge point for stormwater on number 26. Mr Kelett said that the builder, Mr Johns, informed those present at the meeting that, after conducting exploratory digging, he had discovered that the pipes into which stormwater from the defendant's residence ran terminated in the ground as a single pipe on the north-western end of number 26 without any rubble drain dispersing system. Effectively, this had created a single point of discharge of stormwater. 64 Mr Johns' evidence, which I accept, was that he found the point at which the piped stormwater system on the defendant's property ran into the ground as shown in his affidavit, exhibit 7 at annexure MLJ-2. To no avail, Mr Johns subsequently dug an exploratory trench to find a possible connection to the council's infrastructure. 65 Shortly after the site meeting on 18 June 2008, Mr Kelett informed Mr Theunissen of J & K that the stormwater system on number 26 ended with a single pipe in the ground towards the north-west of the property. Mr Kelett also told Mr Theunissen that there was no easement to enable stormwater to be piped over the properties to the north of number 26 (Affidavit pg 8, para 19). 66 Mr Theunissen discussed these issues and potential solutions with his colleague, Mr Walker. They considered the potential implications of utilising a dispersion trench in terms of instability on down slope properties such as that of the plaintiff. I infer from discussions which Mr Theunissen had with Mr Kelett (D7 T 148.25 and T 149.10) that he understood a properly installed dispersion trench would not increase stormwater flows or concentration. In fact, Mr Theunissen understood the opposite, namely, potentially there would be a reduction in both (D7 T 148.25). 67 On 4 July 2008 Mr Kelett received an email from Mr Theunissen in which he attached a sketch of a dispersion trench and suggested this was a possible way of dealing with the stormwater issues at number 26. The sketch is part of Annexure I to Mr Kelett's affidavit. Mr Kelett was unaware at the time of the email that a trench had been dug on the site, having not returned to the site since the meeting on 18 June 2008, (D8, T 226-231). Mr Kelett did not draw any conclusions from the sketch as to Mr Theunissen's desired distance of the trench from the NWB. He considered that had Mr Theunissen intended the trench to be a certain distance from the boundary, he would have put a dimension on the sketch (D8, T 232-237). 68 On 4 July 2008, Mr Kelett sent an email to Mr Theunissen in which he attached a revised dispersion design for a dispersion trench which he considered was less likely to be modified by someone in the future, that is by some innocent homeowner who might acquire the property some years later and unwittingly disturb the system. Mr Kelett informed Mr Theunissen that the builder's advice was that the available length was 9 metres. He also stated that to work effectively the trench needed to be "on a constant RL". This meant that the top lip of the trench had to be level (D9, T 241.35). Mr Kelett understood that the length of 9 metres was the length available in the rear of the defendant's yard where a consistent level could be obtained (D9, T 241.30). The modified design is part of Annexure J to Mr Kelett's affidavit, exhibit 6. 69 Mr Kelett's sketch was part of a possible stormwater system which the geotechnical engineer could recommend. Mr Kelett did not identify an exact location on site (D9, T 243.5) because that was a matter to be determined by the geotechnical engineer, Mr Theunissen (D9, T 246.30). 70 To the extent that counsel for the plaintiff submitted that Mr Kelett was evasive about this sketch whilst being cross-examined, in the sense that it was being put that Mr Kelett in fact identified the location where the trench should be excavated, I do not accept the submission. In my assessment, Mr Kelett gave his evidence in a straightforward, no nonsense way. I accept that Mr Kelett left it to Mr Theunissen to determine where the trench should be located. 71 Mr Kelett then prepared Revision B stormwater plans. These merely showed the inclusion of the dispersion trench. The trench was depicted in a location in the Revision B plans only for the purposes of verification by J & K. This is the reason why the location was shown without dimension. In this respect, I do not accept the plaintiff's counsel's submission that the sketch was intended to be instructive of precisely where the trench should be located. I accept Mr Kelett's evidence about this. 72 Also, at this time, the defendant reviewed Mr Kelett's revision B plans and asked him if there were any alternatives to the dispersion trench plan. Mr Kelett advised that the only viable alternative was to pipe stormwater via an easement. No such easement was available. 73 The defendant then engaged in dialogue with the plaintiff about whether a stormwater easement could be made available to the defendant, or whether the plaintiff would be willing to grant the defendant an easement over the plaintiff's property (exhibit 2, pp 12-15). The plaintiff subsequently refused to grant the defendant an easement over his land for this purpose. The email set out in exhibit 2, para 80 shows that the plaintiff's position was to insist that the defendant must follow what the plaintiff considered to be the Council's "guidelines". 74 During the time these communications were taking place, Mr Theunissen approved the necessary hydraulic drawings. In doing so, Mr Theunissen determined the location of the dispersion trench having regard to the topography of the site at number 26. Importantly, he said in cross-examination that he was concerned to avoid cutting into the toe of the steep slope in the NWB because this could create a risk of the slope failing (D7 T 143-147). 75 Shortly thereafter, J & K confirmed to the defendant that the stormwater management system now proposed would not increase the risk of instability on his property. A modified construction certificate was subsequently issued to the defendant. As far as location of the trench is concerned, I am satisfied that, between them, Mr Kelett and Mr Theunissen agreed that it was Mr Theunissen's responsibility to determine the location of the trench. Mr Theunissen expressly said so in cross-examination at D7, T 146.44. He also said it had to be borne in mind that the precise location was dictated by site conditions so the design had to be "fairly portable" (D7, T 147.6). In any event, the plaintiff did not adduce any expert evidence that locating the dispersion trench further away from the NWB would have made a difference to the final outcome. 76 On 7 July 2008 Mr Theunissen attended at number 26 to view the dispersion trench which was then under construction and gave instructions to the builder, Mr Johns, as to how the trench was to be completed. The inference I draw from all the evidence is that Mr Theunissen was aware of the dimensions of the dispersion trench under construction at that time and approved the completion of the trench in accordance with those dimensions from a geotechnical perspective. 77 Mr Kelett inspected the dispersion trench on 6 August 2008, specifically to inspect the pipe that was in place before backfilling commenced. Mr Kelett was satisfied with the construction up to that stage. Mr Kelett noted that the trench had been moved from where it was shown in his Revision B drawings and in doing so, assumed that J & K had required it to be constructed where it was. This did not concern Mr Kelett. He would have been concerned if the builder, Mr Johns, had located the trench without J & K's knowledge (D9, T 257-258). Accordingly, Mr Kelett instructed the builder to have Mr Theunissen verify the location of the trench during the construction phase. 78 During his inspection, Mr Kelett noted that the northern lip of the trench was not level and there was excavated soil on both sides of the trench. Neither was a problem because the trench had not been completed (D9, T 258). The fact that the builder had installed a plastic pit rather than a concrete one did not matter either because it would have no effect on durability. The use of concrete was not mandatory (D9, T 249-250). 79 Mr Johns evidence was that he dug the dispersion trench according to the specific instructions of Mr Theunissen. When it was put to him in cross-examination that the trench was placed where it currently is for reasons of convenience or cost, Mr Johns firmly rejected that proposition. Further, Mr Johns said he met with Mr Theunissen on site and Mr Theunissen approved the dispersion trench as it was being constructed (D9 T 256, 307 & 308). In addition, Mr Johns' evidence was that the ground in and around the location was hard and firm and not the subject of any visible erosion. Mr Johns gave his evidence in a straightforward way. I consider he did so honestly. I found his evidence convincing and I accept it. 80 On 27 Octrober 2008 Mr Kelett, at the request of the defendant, spoke to Mr Lindsay Dyce at the local council to discuss a proposal for consideration by the Council for diverting some of the stormwater from number 26 onto the Road. After doing an analysis of the site, Mr Kelett prepared the report which is Annexure M to his affidavit. In it, he concluded that it would be possible to reduce stormwater run-off from number 26 by diversion onto the Road, but this was dependent on Pittwater Council's approval, including the Council constructing kerbing on the Road to redirect stormwater to its system. The Council, however, was not prepared to approve this proposal (exhibit 2, para 83). 81 Mr Theunissen agreed in cross-examination that there was no correspondence referring to the possible effect of a dispersion trench on the plaintiff's property at the time of its implementation. However, I am satisfied that Mr Theunissen gave consideration to any possible effects (D7 T 148-150). That there was a good basis for the assumptions which Mr Theunissen made at the time is supported by the evidence of Mr Mark Tooker in his expert reports of 12 November 2009 and 10 December 2009 (exhibit 6). In particular, Mr Tooker's evidence was that the concentration of stormwater flowing across the notional 3 metre strip on the NWB has decreased because of the dispersion trench: the water now flows across a length of 9 metres (D7 T 121). 82 Mr Theunissen's evidence in cross-examination was also that there has been a decrease in the volume of stormwater passing from number 26 into number 24 since the defendant's dispersion trench has been completed. 83 In April 2009 Mr Theunissen advised the defendant that, upon investigation, it could not be practically possible to return the stormwater management system to its original pre-works state, nor was it possible to relocate the dispersion trench. This was because, in both instances, neither proposal would be acceptable from a geotechnical perspective. 84 Mr Theunissen had discussions with the defendant and his colleague Mr Walker about these matters. Mr Walker then confirmed to the defendant in J & K's letter of 16 April 2009 that the installation of the trench was in accordance with the original J & K Report (exhibit 12, annexure F). 85 In May 2009, in order to placate the plaintiff, the defendant approached Mr Wilson about obtaining an easement over his land. Mr Wilson did not agree to grant the easement (exhibit 2 p 328). 86 In terms of other alternatives, Mr Kelett's evidence in cross-examination was that an on-site detention system would not be reasonable or practical if one were to accept the range of storm events complained of by the plaintiff (exhibit 6, pp 22-23). 87 I am satisfied on all the evidence that the dispersion trench was finally completed in August 2009 (see the photograph at p 350 of exhibit 2). As a matter of convenience, the defendant had Mr Kane Georgeson carry out the finishing touches to achieve completion. This was because, at the time, the defendant had engaged Mr Georgeson to do some landscaping work for him. 88 To the extent that the plaintiff instructed his experts that the trench was completed in August 2008, he was in error. 89 On 7 September 2009, officers from Pittwater Council inspected the dispersion trench as a result of a complaint made by the plaintiff about non-compliance with council requirements. Shortly after this inspection, Council wrote to the defendant on 8 September 2009 and informed him that Council's requirements had been met (exhibit 2 p 341). 90 I turn now to consider the lay evidence. 91 In his affidavit in chief, exhibit A, the plaintiff said that prior to the extensions being undertaken by the defendant in 2008 he had not observed any surface water or waterlogged saturated ground in any of the three levels of the rear of number 24 following heavy or prolonged rain events. He also said that in early 2008 he observed what he understood was a dispersion trench being dug on the NWB of number 26, directly adjacent to the upper level of the rear yard of number 24. 92 On the other hand, the defendant said in his affidavit in chief that prior to 2008, and after rain events, he observed the children's cubby area on number 24 would retain water longer than the steep areas on number 26. He also observed that although it was not always soggy, the children's cubby area was always fairly damp after rain events. 93 The previous owner of number 26, Mr Drew, said that during the time he lived in the residence on number 26, number 24 (originally having been part of a single property, all of which was called number 22) was terraced across to number 26. 94 Mr Drew's evidence was that land to the west of number 26 was covered by trees and shrubs and there were no walls or fencing between number 24 and number 26. 95 Although there was no boundary fence on the NWB, there was a surveyors peg which indicated where that boundary was located. Mr Drew described the topography of the land in this vicinity as "a flattish area covered in grass and with no other vegetation". Mr Drew and his family used to play cricket and boulle in that area. 96 Importantly, Mr Drew's evidence in chief in his affidavit (exhibit 7 para 13) was: "I'm aware that after a heavy rainfall the flattish area would become very wet and soggy underfoot. It would usually take a period of some days for the area to dry out again, depending on the amount of rainfall that had fallen. I know this because we would not be able to use the flattish area to play cricket or boulle for between 7 and 10 days after a heavy rainfall." 97 I infer from Mr Drew's evidence that the "flattish area" which he described was bigger than, but includes, the children's cubby area. 98 Mr Drew also gave some useful background evidence when he was in the witness box as follows (D8 T 165.28): "HIS HONOUR: Q. Did I understand your evidence before to be that you used the land at the bottom of your garden running from west to east as a cricket pitch, is that what you were saying - with the kids? A. Yes, your Honour. If I can just give a little bit of background, in case no-one knows. Q. Yes? A. Originally that 22 was owned by a fellow called Mr Silomar(?), and he was the first house up there and he chose them - and he built our house, 26. Q. Right. A. Subsequently he moved out of there and built 22, but he owned all that land and he tiered it all the way down, past where our boundaries were, but eventually it became houses, and so there were no fences, there were no divides, it was all designed to be one huge terrace all the way, and yes, we played cricket and ball there regularly." 99 In particular, Mr Drew's evidence was pertinent when he said that looking from the back of number 26 towards the beach when it would rain (D7 T 161.40): "And it would just flow down. We have a quite steep hill in front of the place and it just ran across the face of that. It was a lot of rain, and when it rained it just ran down the bottom there and that's where we used to play cricket and boulle, stuff like that, and it was always – water always hung around because it's flat down the bottom, yes." 100 Counsel for the plaintiff urged the Court to treat Mr Drew's evidence as largely irrelevant because he submitted that the Court should accept the plaintiff's evidence on this issue. In his submissions (para 72), the plaintiff's counsel sought to rely on paragraph 13 on p 19 of exhibit B (Mr Walsh's second affidavit). However, in that portion of the affidavit, the plaintiff acknowledges that when Mr Drew occupied number 26, the house that existed where number 24 now is discharged stormwater from its eastern side to the flattish area described by Mr Drew. 101 In any event, the plaintiff's main point was, in effect, that Mr Drew's evidence ought be treated as superseded by the fact that all water that used to go onto the flattish area described by Mr Drew is now entirely collected by the new system installed by the plaintiff and taken underground down the hill. Whilst I accept that it is more likely that the new system installed by the plaintiff has assisted in drying out the flattish area described by Mr Drew, the fact remains that the plaintiff's own hydraulic engineer, Mr McGeady, prepared the plaintiff's system on the misguided assumption that surface water from number 26 was piped away through the council's drainage system, which of course was not correct, as the evidence has established. This therefore makes Mr Drew's evidence compelling because it was not suggested that the plaintiff's system would prevent surface water from coming onto his land at the point of the NWB from number 26. In addition, I simply do not accept the plaintiff's evidence about the matter because, for the reasons given in this judgment, I regard him as an unreliable witness. 102 The plaintiff submitted (para 73 of counsel's submissions) that Mr Drew's evidence supports the inference that the flattish area was once drier than it is these days. Because the submission is based on speculation and nothing concrete, I reject it. 103 In addition, the plaintiff himself, as part of his evidence in chief (exhibit B para 4 subpara 8), changed his position from asserting initially that there was no surface water in any of the three levels of the rear yard of his property to the assertion that: "…my observation of the contours of the Walsh and Ginsberg land impacted by the Ginsberg house means that very little of the Ginsberg land previously drained to the north west part of the Ginsburg site." ( Emphasis added ) However, the plaintiff's own expert, Mr McGeady, conceded in the expert conclave that, after the defendant's work was carried out, there was no increase in the volume of water that went from number 26 to number 24 (exhibit 5, D1). 104 As well, the plaintiff's solicitors, in response to an inquiry from the defendant's solicitors, informed them in a letter dated 27 January 2010 that at least 50% of water from number 26 flowed onto both the plaintiff's land and Mr Wilson's land before extensions were carried out. This was contrary to the plaintiff's own evidence in chief that there was no surface water flow in any of the three levels of his rear yard (exhibit A paras 1-5). 105 In his second affidavit (exhibit B, para 4, subpara 35) the plaintiff said that prior to the defendant commencing his renovations, stormwater drained into the northwest corner at the base of the verandah, nine millimetres from the northern boundary. However, in his letter to the defendant dated 25 May 2008, the plaintiff asserted that "… at present all the stormwater from your property including the roof drainage is dispersed aboveground at the bottom of your property directly on the boundary of our property" (exhibit 2, pg 222). 106 The plaintiff further asserted (exhibit B, para 4, subpara 15) that prior to the defendant undertaking alterations to number 26, water was either absorbed by the ground or flowed in a northerly direction because of some stone flagging which he claimed directed water from west to east. The assertion is contradicted by the following facts: (a) The contour in the front end of the defendant's garden drops approximately 4.57 metres and (b) Reading the contour map correctly, that is by taking a perpendicular line to the contour line, it can be seen that water flows to the NWB along contour points 59.87, 58.40, and 57.76, a drop of 2.1 metres. Therefore, water would not flow uphill from west to east, as the plaintiff would have it. 107 The plaintiff also asserted that there was no change in the level of the children's play area as asserted by the defendant (exhibit B, para 4, subpara 36). However, the photographs annexed as B11 and B12 demonstrate that there has been an increase in the level. In addition, the plaintiff conceded that he had added 10 mm of sand (exhibit B, para 4, subpara 22) when couch grass was laid in the area. In this respect, the work was done by Peter Yorke. The plaintiff did not call him as a witness and I therefore draw the inference that Mr Yorke's evidence did not support the plaintiff's case. 108 In my assessment, the plaintiff's mindset has always been that the defendant has wronged him and he will take whatever steps are necessary to have this rectified. As I have demonstrated above and below, this caused him to shift the basis of his complaint in order to achieve the desired result. In this respect, the plaintiff's legal advisers, who put everything they could on behalf of their client to the Court, sought to reframe their client's evidence by suggesting the Court should look upon it as the sort of "fixations that sometimes distort the evidence of even honest plaintiffs". This was a valiant, but unsuccessful, attempt to dissuade the Court from making an adverse credit finding against the plaintiff. 109 At the beginning, the plaintiff's complaint was that the defendant had not connected his stormwater discharge to an existing underground stormwater system. This was made clear in the plaintiff's email to the defendant of 25 May 2008 (exhibit B p 45). 110 Then, on 10 August 2008, the plaintiff suggested that the defendant's stormwater discharge should be dealt with by the "easement for services (sic) exists located on the eastern side of your land". No such easement existed. 111 The plaintiff also asserted, erroneously, that the defendant had failed to comply with council guidelines (exhibit B p 47). The plaintiff threatened the defendant that unless "relevant approvals from council and documentation provided by your consultants" were received by 4pm on 11 August 2008, then the matter would be referred to his solicitors (exhibit B p 46). This remained his fixation. 112 In his email of 13 August 2008 (exhibit 2 p 228), the plaintiff informed the defendant he had been advised by his solicitors that the plaintiff's "stormwater works had been constructed illegally. … you have left us no choice other than to proceed down the required legal avenue with council and your accredited certifier, notifying them of the non-compliant works." In this context, the plaintiff gratuitously asserted that the defendant's technical engineers were "unprofessional and incompetent". 113 The plaintiff did not report any real or concrete damage to his property having occurred during this period apart from an occasion in May 2008 when he complained about muddy water coming onto his land from excavated holes on the defendant's property. The defendant immediately took steps to relocate a silt fence. This prevented any muddy overflow onto the plaintiff's property. As well, in order to safeguard things whilst work was underway, the defendant installed a drainage pipe to redirect stormwater (D9 T 298-302). The plaintiff complained about this pipe and assumed it was permanent when, in fact, the installation was a temporary measure only. 114 That the plaintiff had a bee in his bonnet about the defendant not complying with council guidelines is made abundantly clear in his email to the defendant dated 4 September 2008 (exhibit 2 p 235) where he says: "Interesting comments made, what I do want you to do is to follow the f…..'n guidelines of council!!!!!!!! comply with your DA consent conditions!!!!! Being condition 'C2'. This was not undertaken at all which is complete negligence!, condition 'C6', condition 'A5', condition 'B11', condition 'D1'. Maybe you should avail yourself in reading your development conditions by Pittwater Council and action them. Sorry mate but I think you are being completely naïve if you think we would agree to granting 26 … an easement over our land burdening our land for the rest of its life including devaluation?" 115 I note no mention in the email of actual damage to the plaintiff's property. 116 At this point the emails sent by the plaintiff to the defendant demonstrate that he was an extremely angry man who had lost all objectivity in terms of speaking reasonably with his neighbour about the perceived problem concerning the flow of water from number 26 onto number 24. Although earlier discussions were directed towards a stormwater solution as between neighbours, once the plaintiff realised that in the normal course of events there was no infrastructure into which the defendant could discharge his stormwater and that it was inevitable that water which traditionally flowed onto the plaintiff's property from the defendant's property would continue to do so, the plaintiff became very hostile and extremely aggressive. It is not coincidental that his allegations of actual damage only surfaced in September-October 2008 when it became clear to him that the water could not be discharged into the council's infrastructure. 117 On 13 August 2008 the plaintiff's solicitors wrote to the defendant (exhibit 2 p 251) and asserted that the defendant's "proposed stormwater dispersal method has not been designed by an appropriately qualified hydraulic engineer and has not been approved in accordance with the provisions of the Environmental Planning & Assessment Act 1979". The plaintiff asserted the potential of landslip caused by the drainage works. An action in nuisance was mentioned for the first time. This was done in the following context in the plaintiff's solicitor's letter: "Our client is concerned that the proposed method of damage will cause a nuisance and/or landslip to his property." ( Emphasis added ). 118 Notwithstanding the solicitors' complaint, there is no evidence that at that stage the plaintiff had engaged an expert to look into the matter on his behalf to support the assertion made through his solicitor that there was a potential for damage to his property, particularly by way of landslip. The plaintiff did not instruct his hydraulic engineer, Mr McGeady, to attend the premises until some time in September 2008. 119 In his email of 10 September 2008 to the defendant (exhibit 2 p 240), the plaintiff continued to base his complaint on the alleged failure by the defendant to comply with council requirements. In the same email the plaintiff threatened the defendant. He said that legal costs would be extremely high, that he was an experienced litigant who worked regularly with solicitors and barristers and unless the defendant complied with council requirements within a specified timeframe, the plaintiff threatened that he would "not look back". There is a sense of outrage contained in the email to the effect that the defendant was interfering with the plaintiff's proprietary interests and, come what may, the defendant would have "a lot to answer for" if the matter went to court. After telling the defendant that the choice was his, the plaintiff sarcastically concluded his email as follows: "Have a nice day. Thanks for giving us this enjoyment of living in our street!!!!!!" 120 A review of the emails and correspondence demonstrates, on the other hand, that at all times the defendant was attempting to be cooperative. 121 It was only much later on that the plaintiff conceded he was totally in error in asserting that the defendant had an easement he could access into which stormwater could be channelled. The plan that the plaintiff had based his assertion on related to sewerage lines only. Importantly, by this time, when he realised he was in error and wrong about the existence of an easement, the plaintiff was committed to bringing these proceedings against the defendant, a position which he has never resiled from. 122 That the plaintiff was prepared to change his case in order to prove a change in water flows is demonstrated by the following evidence. 123 First of all, the plaintiff asserted that the dispersion trench was operational in August 2008 (exhibit A, para 7) but then he later said it was a temporary measure and still under construction at that time (exhibit B, email dated 10/8/08, p 46). Next, the plaintiff said that the trench was completed on 28 July 2008 (exhibit B, para 4, subpara 96). 124 The plaintiff asserted, particularly through his expert Mr McGeady, that the defendant's work had resulted in a greater area of hard surfaces. But in his expert report in reply, Mr McGeady accepted (exhibit O, pg 4, para 9), that, relevantly, the calculations relied on previously to support this assertion were incorrect. 125 As already mentioned, the plaintiff commenced his case by alleging that water flows had been increased from number 26 to number 24 as a result of the work done by the defendant. The plaintiff relied on Mr Crozier's evidence (exhibit K) that the increase was in the order of 200%. As already mentioned, Mr McGeady accepted that there had been no increase in volume. And Mr Crozier deferred to Mr McGeady (D7 T 64.5). 126 I was unimpressed with the plaintiff whilst he was giving his evidence. His responses were quite often aggressive, he was inclined to make speeches, a lot of his answers were unresponsive and he sought to avoid answering questions if there was a possibility that his answer might favour the defendant. It was only when he realised that counsel had him cornered with reference to a document or something which was concrete, that the plaintiff was prepared grudgingly to acknowledge the correctness of the matter being put to him. The plaintiff was in the witness box for quite a while. I therefore had a good opportunity to assess him in terms of credibility and truthfulness and so on. I have come to the conclusion that the plaintiff is not a credible or reliable witness. The plaintiff is obsessed with proving that the defendant has done him wrong and is prepared to do or say anything to achieve this outcome. 127 Accordingly, I am only prepared to accept those parts of the plaintiff's evidence which are uncontested or are corroborated by accepted oral testimony of other witnesses or documentary evidence. 128 It is convenient at this point to record my assessment of the defendant. In my assessment, Mr Ginsberg was also inclined to make speeches and he was certainly conscious of there being a real "contest of egos" between him and the plaintiff, so that, here and there, he may have been inclined to exaggerate a bit. However, having said that, overall I am satisfied that the defendant is an honest and reliable witness. In any event, although important, it is not the Court's acceptance of the defendant's evidence which is the critical factor in this case. To an important extent, the Court's determination arises out of its consideration of the expert evidence and the conclusions which the Court has reached about that evidence. 129 I accept the defendant's evidence that, prior to any of the renovation work being done on number 26, most of the water on his property flowed to the NWB and that he did not ever observe any damage to either lawn or trees on the plaintiff's land. I also accept his evidence that dry rock walls, which were the subject of complaint by the plaintiff, were always in that condition. 130 The plaintiff relied on the evidence of his gardener, Tristan Lange. Mr Lange did landscaping work for the plaintiff during October 2008. Mr Lange said the works were done in proximity to the NWB. 131 In his evidence in chief, Mr Lange identified the work undertaken with reference to certain invoices annexed to his affidavit (exhibit G), which bore the date "Oct 08". Mr Lange also said that he did the work because vegetation at number 24 was either "dead or damaged due to waterlogged soil conditions". He said he observed that grass was waterlogged to the point of saturation and was beyond repair. 132 Mr Lange conceded in cross-examination that the invoices he was relying on in giving his evidence in chief were not, in fact, created in October 2008, but had been created in June 2009. Moreover, the narratives included in the invoices were not in the original form of the invoices and Mr Lange had "binned his diary" before reconstructing the invoices. Mr Lange conceded he had a discussion with the plaintiff during which he was "asked to find more information on these invoices" (D7 T11). Specifically, the plaintiff informed him there was a problem with water from the neighbouring property, that the case was going to court and that the plaintiff needed more information about what the invoices were about. Although Mr Lange insisted that the plaintiff did not tell him what to put in the invoices, he was unable to satisfactorily explain to the court why it was that he provided comments in some of the invoices about water damage when all he had been asked to do was record what work had been done. As well, Mr Lange conceded that in relation to the planting of lilly pillies, his invoice recorded this as having been done in October 2008, whereas he said in fact the lilly pillies were planted in June 2009. He then said that this work had been done in June 2008. Similarly, Mr Lange conceded that the planting of trees recorded in his invoices as being done on October 2008 had occurred earlier that year. 133 While I do not consider Mr Lange was deliberately untruthful in giving evidence, I do not accept his evidence because I consider him to be an unreliable witness. The evidence I have summarised above demonstrates why I have come to this conclusion. In addition, I have taken other matters into account. First of all, although he sought to assert that some of the plants on number 24 were not thriving due to water damage, Mr Lange did not refer in his reasoning to other possible causes such as change of season, soil composition and where it was appropriate for the plant to be located. Secondly, when convenient, Mr Lange relied on photographs to demonstrate a point, but when they tended to contradict his evidence, his standard response was that he could not see the photograph clearly (for example: see D5 T34). Thirdly, Mr Lange made no record of any complaint made to him about the ground conditions. This is important because in August 2008 the plaintiff said he would start gathering evidence in his case against the defendant (D3 T60). Finally, although Mr Lange knew there was a dispute between the plaintiff and the defendant, he destroyed his diary for 2008. The inference I draw in the circumstances is the diary would not support his testimonial evidence. In addition, I am satisfied that the material included in the invoices, after Mr Lange's discussion with the plaintiff, was information provided by the plaintiff to Mr Lange in order to establish damage and thereby enhance his prospects of succeeding in his claim against the defendant. In passing, I note that the information contained in the invoices bears a remarkable similarity to the material contained in the plaintiff's expert's reports. 134 The plaintiff had initially refused to produce, through his family company, the original invoices provided by Mr Lange. When they were eventually produced under subpoena, the invoices demonstrated that in the period August to September 2008 no mention was made of damage whatsoever by Mr Lange (exhibit 1, tab 30). 135 In all the circumstances I conclude that the plaintiff had Mr Lange recreate his invoices with a view to establishing that returfing of his lawn was necessary because of water damage caused by the defendant. I am also satisfied that the real reason for returfing the lawn was to change the landscaping at the NWB to ensure "privacy screening" (exhibit B, para 4, subpara 114). In this respect, I have taken into account the fact that as at 18 September 2008 only one rain event had been complained of, being 5.8 mm in June 2008 (exhibit B, B18). After this date, although there were numerous letters written complaining about the defendant's non-compliance with council guidelines and so forth, no mention was made of how or in what manner the plaintiff's lawn had been damaged. Furthermore, no complaint was made in October 2008 that waterlogged trees had been removed, nor had any complaint been made in July or August 2008 that the lawn was waterlogged. 136 At the view which the court had the benefit of, I observed that the children's play area was duplicated at the lower end of the plaintiff's garden. No complaint has been made about the ingress of water to that particular area. That is important because the plaintiff asserted that he had been forced to take his children to outside parks as a result of water damage done to the children's play area, when clearly nothing prevented the family from engaging in recreational activities in the area lower down. This gross exaggeration further demonstrates why the evidence of the plaintiff should not be accepted. 137 As far as the plaintiff's photographs and videos are concerned, these do not support a case based on a "before" and "after" scenario. They are merely evidence that water has always flowed from number 26 onto number 24. 138 In conclusion, I do not accept the plaintiff's evidence about damage. I am satisfied that his evidence about it was constructed when the plaintiff realised he had an onus to discharge in terms of satisfying the court that there was material damage to number 26 beyond the de minimis level. In this respect, I accept the submissions made by the defendant's counsel in paragraphs 46-49 of his written submissions. 139 I am also satisfied that the history of complaints (see annexure 'A' to the plaintiff's counsel's written submissions in reply) do not support the case on damage which the plaintiff sought to make out. 140 I turn now to deal with the evidence of the experts. 141 The plaintiff sought to support his case by calling evidence from geotechnical and hydraulic engineers. 142 The geotechnical evidence was given for the plaintiff by Mr Crozier. Very little weight was placed on Mr Crozier's evidence by counsel for the plaintiff in his written submissions in chief and in reply. That is understandable, because Mr Crozier clearly did not understand his obligations to the court under the expert witness code. In fact, he conceded that his report was prepared more as a negotiating tool than anything else (D6 T37). I accept the submissions made by counsel for the defendant that Mr Crozier's report displayed no intellectual rigour, no forensic science and it did not contain any observation which the court could rely on to establish damage had occurred to the plaintiff's property or that there was a risk of damage occurring. 143 Although Mr Crozier said he had observed damage, he did not take any photographs, make any contemporaneous notes or produce any forensic evidence to support his observations. In cross-examination, when asked to elaborate about trees that he said were dying, he identified an area on the northern boundary that is not the subject of any complaint made by the plaintiff. Mr Crozier also accepted that he had not looked at earlier documentation, including that emanating from his own firm, where reference was made to a limited risk of damage due to the slope and gradient of the properties before work was done on either number 24 or number 26 (D6 T37&38). On the other hand, Mr Crozier asserted propositions about ground conditions being regularly saturated which were unsupported by the plaintiff's evidence. Finally, in cross-examination, Mr Crozier conceded that the calculations he had made were incorrect (D6 T47&48). 144 I therefore do not accept Mr Crozier's evidence. 145 The defendant relied on the geotechnical expertise of Mr Theunissen. Mr Theunissen conducted penetrometer testing at a court ordered inspection on 30 October 2009. Three bore holes were completed and the results of the testing are set out in annexure J of Mr Theunissen's affidavit. 146 Mr Theunissen's evidence was that he did not encounter any ground water whilst drilling the bore holes, notwithstanding that in the 15 days prior to the investigation, 128.6 mm of rain had fallen in the vicinity. In this respect, bore hole number 103 was located on the defendant's property between the dispersion trench and the brushwood fence on the boundary. 147 During this inspection Mr Theunissen made observations about the children's cubby area and the small terrace and sandstone ledge outcropping immediately to the north of that area on number 24. His observation was that the grass was predominantly green with areas of brown spots. It was not covered with water or wet underfoot. In Mr Theunissen's observation, there were no signs of distress or bulging in the proximate sandstone retaining walls. He said the seepage flowing down the sandstone ledge to the north of the terraced area was not unusual in light of the terrain and it was not turbid. Therefore, this did not suggest erosion had occurred. If anything, it may have been the result of the operation of a nearby sprinkler system. Mr Theunissen also observed no evidence of soil saturation or surface erosion and there was no evidence of any failure of a sandstone retaining wall. 148 Mr Theunissen concluded from the inspection done on 30 October 2009 that the children's cubby area had been predominantly filled to create a more level area. 149 Mr Theunissen essentially stuck to his guns whilst he was cross-examined and I accept his evidence. 150 In response to assertions made by Mr Crozier that "good hillside practice" had not been followed, Mr Theunissen said that it would not have "been hillside practice" to implement an absorption drain on number 26. Rather, the installation of the dispersion trench was proper practice because the trench dispersed previously concentrated water flows over the entire length of the trench. 151 Mr Theunissen was asked to accept the conclusions of Mr Tooker in his report. Having done so, Mr Theunissen commented on the geotechnical impact of the dispersion trench installed at number 26 in his expert report of 12 November 2009, also part of exhibit 6. Mr Theunissen's conclusion was that the risk of slope instability had decreased as a consequence of a decrease in the total volume of water entering number 24 from number 26. To the extent that there was a small increase in flow rates as found by Mr Tooker, Mr Theunissen said that this would have a negligible affect on number 26 in terms of gully erosion because the land on number 24 immediately north of number 26 was terraced level and not susceptible to erosion. 152 At the conclave of geotechnical experts, the results of which are contained in exhibit M, Mr Crozier, Mr Walker and Mr Theunissen all agreed that a decrease in volume would reduce the risk of slope movement. Only an increase in volume which was more than slight would increase the risk of slope movement. 153 Stewart McGeady gave the hydraulic engineer's evidence relied on by the plaintiff. Mr McGeady's evidence was largely based on an observation he made from a photograph that all water entering the dispersion trench was dispersed only over the length of 3 metres on the NWB. However, this photograph was taken at a time when the dispersion trench had not been completed. Mr McGeady also said in his evidence in chief that a significant portion of the water which flows onto number 24 comes from Mr Wilson's property (exhibit N pg 9). Of course, Mr Wilson is not a party to these proceedings. 154 Mr Parsons is a surveyor whose evidence, which I accept (exhibit 7), was that the dispersion trench is now level. Mr McGeady was asked to assume Mr Parson's evidence was accurate. In doing so, Mr McGeady conceded that his earlier opinion that water was being dispersed only over a length of 3 metres, was no longer appropriate (D7 T87). In the experts conclave Mr McGeady accepted that there had been no change in volume of water (although he maintained that there was an increased flow rate). Mr McGeady accepted that if the trench dispersed for the full 9 metres length, that there was no concentration of stormwater flowing from number 26 onto number 24. Mr McGeady further accepted that his calculations in relation to impervious areas were wrong and in fact the size of the impervious areas had been reduced (D7 T84). 155 Mr McGeady conceded in cross-examination that, in designing the stormwater management system for the plaintiff's property, he had assumed that the defendant had his own piped stormwater management system in place. Mr McGeady said had he known the true position, he would have designed the plaintiff's stormwater system to deal with any stormwater coming from number 26 (D7 T 109-110). 156 The defendant relied on the expertise of Mr Mark Tooker, a very experienced hydraulic engineer with 30 years experience in water and civil engineering. Mr Tooker was truly independent in the sense that the other engineering experts who gave evidence were all involved, one way or another, in work which had been done at number 24 or number 26. I found Mr Tooker's evidence to be particularly persuasive and I prefer it to that of Mr McGeady. 157 Mr Tooker's reports dated 12 November 2009 and 10 December 2009 are part of exhibit 6. I shall not detail in this judgment the assumptions made by Mr Tooker which are clearly set out in paragraph 2.2 of his initial report. However, it is important to note the opinion he expressed in his initial report as follows: "During a minor rainfall event the roof gutter drainage system would convey flows to the pipe drainage system to the rainwater bladder. Once the storage capacity of the bladder is exceed(ed) rainwater would flow to the dispersion trench and percolate to the surface and flow through to No. 24. During an event greater than the downpipe capacity, surcharge will occur at the ground level at the downpipe locations in addition to the flows that percolate to the surface through the dispersion trench at the boundary." 158 In his initial report Mr Tooker described the methodology and computer modelling used by him to calculate stormwater flows both pre-extension and post-extension in terms of flow rates (measured in litres per second) and velocities (measured in metres per second) and he sets out the results of his calculations as to flow rates at tables 3.2 (pre-extension) and 3.3 (post-extension). The results of his calculations as to velocities appear at table 3.4. 159 Importantly, in preparing his report, Mr Tooker adopted the same approach as Mr McGeady in dividing up the water flowing from number 26 to number 24 into the 3 metre strip at the western end of the NWB and the remainder in order to provide a comparison with the figures in Mr McGeady's report. 160 Mr Tooker's conclusions based on his calculations as to flow rates and velocities were that: (a) the peak flow rate over the western 3 metres of the northern boundary to number 24 had been decreased; (b) velocities over the western 3 metres of the northern boundary to number 24 had been decreased; (c) there had been an increase in peak flow rates across the northern boundary to number 24 in the order of 4-14%. 161 In calculating the peak flow rates, Mr Tooker did not take into account the effect of the rainwater retention tank. He agreed that an increase in flow rate meant that stormwater gets to the dispersion trench more quickly than it would if it were flowing overland. He therefore calculated the level of increase. Having done so, Mr Tooker concluded that the increase in flow rates did not constitute a significant change from pre-extension to post-extension and that any increases in velocities were very small. 162 I accept Mr Tooker's rejection of the suggestion that a change in flow rates had produced an increase in concentration of stormwater flowing from number 26 to number 24. His evidence, which I accept unreservedly, was what had occurred as a result of the installation of the dispersion trench was that there had been a reduction in the concentration of stormwater flowing across the 3 metre strip on the NWB (D7 T121). 163 Mr Tooker also commented in his report about the 6,000 litre rainwater bladder installed on number 26. Based on a published study annexed to his report of 10 December 2009, Mr Tooker was of the opinion that this tank would provide a flow detention role in the stormwater system of approximately 2,000 litres, causing the flow volume to be reduced. Although the retention effect of the tank would not reduce peak flows for storm events greater than, and including one year ARI, it would nevertheless reduce the volume of each storm event by approximately 2,000 litres. 164 Mr Tooker also did his own modelling of the volume of stormwater which would be reduced by the rainwater tank. This model separated internal demand from irrigation demand. Mr Tooker concluded, using his modelling, that the volume of stormwater runoff from number 26 to number 24 has been reduced on an average annual basis by some 29,000 litres per year. 165 Taking into account the full range of storms and bearing in mind that before the defendant did the work to his property some water would have discharged on the ground, Mr Tooker nevertheless concluded that the system installed by the defendant has not resulted in an increase in volume of stormwater discharging onto number 24 even if the reduction in volume of the rainwater tank is excluded. 166 Mr Tooker's evidence was that, prior to the plaintiff installing a retaining wall on the north-south boundary between number 24 and number 26 which has prevented a flow of stormwater from number 26 to number 24, some of the stormwater generated on the western side of number 26 would have flowed over the north-south boundary between the two properties. 167 In the hydraulic experts' conclave (exhibit 5), Mr Tooker agreed that this alteration effected only a "nominal change". More importantly, Mr Tooker expressed the opinion, which I accept, that the landscaped garden wall edging to the garden bed immediately below the NWB on number 24 creates ponding on both number 24 and number 26. 168 Issue H1 in exhibit 5 concerned a potential alternative to the system installed by the defendant. Mr Tooker told the court that he did not consider there was a need for further controls because the control of flows and velocities at the NWB were both adequate and appropriate (D7 T136). He reiterated that there was no significant change to water flows after the defendant had done the work on number 26 in terms of the flow getting onto number 24. He also said that the water flows were being dealt with on number 24 as they should be (D7 T138). Mr Tooker noted in this respect that stormwater entering number 24 from number 25 (that is, not the defendant's property) was being piped from number 24 to the council's drainage system. 169 Mr Kelett also gave expert evidence for the defendant in his capacity as an expert hydraulic engineer. He agreed with Mr Tooker during the experts' conclave that there was in fact a reduction in concentration as a consequence of the installation of the dispersion trench and that there was no greater volume of stormwater flowing from number 26 to number 24. In fact, there was a reduction in volume due to the installation of the rainwater tank. The rainwater tank also reduced the flow rate. Mr Kelett also agreed with Mr Tooker that the landscaped garden wall edging on number 24 had created ponding of stormwater on both number 24 and number 26. 170 Mr Kelett did his own calculations, the results of which are set out in tables at pages 12 and 13 of his report. In summary, Mr Kelett found no increase in stormwater flow rates in the post-extension scenario and one instance of a slight decrease. Mr Kelett's calculations were done on the basis that the rainwater tank was full and did not take any stormwater out of the system. 171 The plaintiff suggested Mr Kelett conceded that impervious material was put on the lip of the dispersion trench and would disturb the proper functioning of the trench. However, there is no evidence that any material was placed on the lip of the trench between it and the NWB. Even if the contour of the land was left in its natural state, then water would flow over the dispersion trench onto number 24 in an even and regular manner. This could not occur because the plaintiff has placed an artificial wall on his side of the NWB by attaching plastic borders of the garden bed on number 24 to the log on which the boundary fence has been placed. This prevents water from flowing over the NWB in its natural, intended course. 172 Mr Kelett provided an opinion in his report at pp 22-23 about potential alternative stormwater management systems for number 26. He said that whilst site detention systems were used to control storm events of five year ARI or greater, that was not necessary where the situation was one of frequent rainfall events being experienced for the majority of the time such as the plaintiff had complained about. Therefore an onsite detention system was not necessary, reasonable or practical at number 26. 173 Similarly, it was not practical to discharge any stormwater flow onto the Road unless permitted to do so by the council and, of course, the evidence establishes that the council had not agreed. In any event, apart from this, Mr Kelett's evidence, which was compelling, was that for such a system to work it would be necessary to install a holding tank and that power can often be lost to the pump which takes water to that tank in large storms. In other words, this type of system does not work reliably. The only way to endeavour to overcome that would be to put the tank at such a height above ground level to provide gravity fall to the street and this would raise design and planning permission issues (D9 T 286). It was also obvious from my view of the scene that such a solution would be an awful eyesore. 174 I also accept the evidence of the defendant's landscaping experts in preference to that of Mr Lange. 175 Both these witnesses were truly independent experts. 176 Mr Peter McMaugh gave evidence (exhibit 8) that the soil which he observed which was coloured red or yellow demonstrated that the iron compound in it had oxidised. Therefore, that soil was not waterlogged. Waterlogged soil would become anaerobic and have a grey appearance. 177 Mr McMaugh referred to the pictures attached to his affidavit labelled PM 27 and PM38. These show oxidised clay and demonstrate that the long term soil condition relating to the soils complained of by the plaintiff are not now and have not been waterlogged. 178 Mr Kyle Hill gave evidence in exhibit 10 that photograph B27 annexed to the Plaintiff's second affidavit, exhibit B, showed a surface which was not typical of a waterlogged soil surface and said there was no evidence of surface puddling of water. There was a lack of consistency in relation to the browner areas compared to the greener areas. 179 In exhibit 11, Mr Hill gave evidence that some of the brown patches in B27 are typical of turf that has just been mowed or the edges cut where the green surface leaves have been removed. This type of turf can be expected to grow back rapidly. 180 Mr Hill also differentiated between saturated and waterlogged grass. His evidence was that waterlogging is the point past saturation where puddles are likely to appear on the surface of a waterlogged area. The plaintiff did not produce in evidence any photographs with water puddles on the turf. 181 Mr Hill also gave evidence that if the ground was saturated that one should be able to see and feel the moisture content. He said it was not difficult to collect evidence of saturated soil. By removing turf to the soil level, soil saturation can be observed. It would most likely be very moist if there had been saturation. Apart from the evidence of the plaintiff and Mr Lange, there is no independent evidence that the soil on number 24 was saturated and moist. 182 Taking all the evidence into account and apart from the findings set out above, in summary, the court makes the following findings in respect of which it is comfortably satisfied that: (a) The flow of water from the defendant's land onto the plaintiff's land is no more concentrated than it was before the defendant carried out the work on his land. (b) There has been no increase in volume of runoff of water from the defendant's land to the plaintiff's land since the defendant carried out the work on his land. (c) The plaintiff's property has not been materially damaged by the defendant's work. (d) The comfort, enjoyment and value of the plaintiff's land have not been diminished or unreasonably interfered with by the work done on the defendant's land. (e) There is no reasonable apprehension of material damage in the future as a result of the defendant's works. (f) Any inconvenience suffered by the plaintiff as a result of the defendant's works was temporary and of a minor nature. It was no more than other occupiers in the same location could have been expected to bear. (g) The defendant has conducted himself reasonably in addressing the stormwater management issues on both properties. 183 It follows that the plaintiff's claim should be dismissed. In the result the Court makes the following orders: 1. Verdict and Judgment for the Defendant. 2. Direct that the exhibits be returned. 184 I will not make an order as to costs until I receive further submissions from the parties' counsel. ********** DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. 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