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Graham v Alic[2022] QDC 106



Graham & Anor v Alic & Anor [2022] QDC 106


Philip William Graham and Naomi Louise Sunderland



Flaviu Riolan Alic and Nona Mirela Alic







Originating Application


District Court at Brisbane


28 April 2022 (ex tempore)




8, 11, 27 & 28 April 2022


Jackson QC DCJ


  1. The respondents are to:
    1. (a)
      demolish the timber retaining wall presently located on the respondents’ property immediately adjacent to the boundary between the applicants’ property and the respondents’ property (“the Existing Retaining Wall”);
    2. (b)
      construct a retaining wall, to replace the Existing Retaining Wall, which:
      1. is to be designed and built according to plans approved and certified by an engineer nominated by the president of Board of Professional Engineers of Queensland.
      2. includes as part of its design and construction, adequate and reasonable drainage necessary the abate the nuisance identified in the Reasons for Judgment.
  2. The preceding order be stayed for three months from the date of this order.
  3. Liberty to the parties to apply on three days’ written notice to the other party in relation to the operation of orders 1 and 2.
  4. The respondents are to pay the applicants’ costs of and incidental to the proceedings:
  1. (a)
    up to and including 11 April 2022 on the standard basis;
  2. (b)
    thereafter, on the indemnity basis.


NUISANCE – NATUAL AND REASONABLE USE OF THE LAND – CONCENTRATION OF SURFACE WATER – Where the applicants claim that works undertaken on the respondents’ property have interrupted the “natural flow” of water – Where the applicants claim that works on the respondents’ property have increased the concentration and velocity of water flowing onto their property – Where the respondents submit that the works on their land are a reasonable and natural use of their land – Whether or not the respondents have created a nuisance to the applicants’ property.

INJUNCTION – Whether an injunction should be granted.

DAMAGES – Where the applicants claim they have suffered damage – Whether damages should be awarded.


Bell v Pitt [1956] Tas SR 161

Corbett v Pallas (1995) 86 LGERA 312

Gales Holdings Pty Ltd v Tweed Shire Council (2013) 197 LGERA 381

Gartner v Kidman (1962) 108 CLR 12

Kraemers v Attorney-General (Tas) [1966] Tas SR 113

State of Queensland v Baker Superannuation Fund Pty Ltd [2019] 2 Qd R 146


P Somers for the applicants

M McDermott for the respondents


Bennett & Philp Lawyers for the applicants

Frangos Lawyers for the respondents


  1. [2]
    The applicants and the respondents are neighbours.
  2. [3]
    The applicants live at 26 Fernhill Place, Diddillibah (“the applicants’ property”) and have done so since 30 June 2017. The respondents live on a higher contiguous lot at 22 Fernhill Place, Diddillibah (“the respondents’ property”). The respondents have owned their property since 27 August 2013 but did not commence building on it until 2015.[1] Construction was commenced on or about 29 June 2015.  The original part of the retaining wall, and associated filling works were completed on 12 September 2015, before the house, which was completed on 10 August 2016, and the pool in 2017.  An extension to the retaining wall was constructed in February 2019.  The respondents’ property is naturally elevated well above the applicants’ property. A timber sleeper retaining wall (“the retaining wall”) situated on the respondents’ land[2] serves to retain the respondents’ land over a distance of approximately 52 metres, about 13 metres of which was added in 2019.
  3. [4]
    The respondents cut the natural slope of their land where the house was to be built and used the fill to create a flat area below their house and swimming pool.  There are battered slopes above the flat area (immediately below the pool area) and below the flat area (and above the retaining wall). The amount of fill is estimated to approximate 800 cubic metres.  Additional topsoil was added to this flat area and there may have been some further shaping in August or September 2018, although there is some dispute as to the extent of this.  The extent of the minor reshaping is perhaps best observed from the diagram which is at page 2 of the exhibit bundle to Dr Alic’s affidavit filed 24 March 2022. The resulting slope was a little steeper but the changes are relatively minor.    As part of this, a bund (“the effluent bund”) at the northern edge of the flat area above a cut-batter sloping down towards the retaining wall was removed.  In 2019, the respondents’ effluent disposal area which was located in this flat area was relocated to the rear of the respondents’ property.
  4. [5]
    The trial proceeded over 4 days and there was a view on the day before the trial commenced.

The pleaded case and the nature of the alleged nuisance

  1. [6]
    The applicants’ claim proceeds on the basis that works undertaken by the respondents on their land have created a nuisance by interrupting the “natural flow”[3] of water from the respondents’ property to the applicants’ property.  As will become apparent, at first, the applicants’ expert evidence did not consider the “natural flow” in the sense of comparing the natural state of the land with that as developed.[4]  It instead proceeded on the basis that it was relevant to compare the position when the applicants’ house was built, complete with extensive hardstand areas all drained to the road or the conservation area at the rear (but no filling works had been undertaken), and the position once the works on the respondents’ land were complete.
  2. [7]
    In my view, there are two problems with that approach.  First, the relevant comparison is with the natural flow of the land and not some hypothetical flow part way through a proposed development.  The position may well be different for land part of which has been developed well before a relevant change is made.  Secondly, this hypothetical point never existed apart from some slab-works in relation to the house because the respondents completed the filling and retaining works before the house was completed.  

The respondents’ works

  1. [8]
    The applicants claim that there were two critical occasions upon which flow was interrupted causing difficulties for their property. First, when the respondents built their house and the retaining wall and placed fill behind that wall thereby building up the land (“the 2015 works”).  The curiosity with that claim is that no issue is said to have arisen until October 2018,[5] although the nature of subsequent works in 2018 (“the 2018 works”) included the removal of the effluent bund which may have served to reduce an effect of the earlier works.  Secondly, in 2018 when the respondents added topsoil to the property and altered the shape of the slope towards the applicants’ property.
  2. [9]
    As to each of these matters, the applicants’ position is that:[6]

“[The 2015 works] have had the following hydrological effects:

  1. (a)
    The additional fill placed adjacent to the boundary has:
  1. (i)
    caused the land to now be built up to above 1 metre in parts directly adjacent to the boundary, retained by a wall the respondents built; and
  1. (ii)
    increased the slope of the respondents’ property in the immediate 1 to 2 metres above and back from the retaining wall;
  1. (b)
    The additional fill acts as a sponge, soaking up rainwater as it flows towards the applicants’ property;
  1. (c)
    The retaining wall stops that natural flow across the length of the boundary between the two properties;
  1. (d)
    The built-up water in the soil above the retaining wall discharges in gaps under the wall, in the wall, and on isolated occasions, over the top of the wall;
  1. (e)
    Compared to the natural flow of water over the properties, the change in the flow has resulted in:
  1. (i)
    a more concentrated flow where the water escapes under and through the retaining wall;
  1. (ii)
    water being released from behind the wall for an extended duration.”
  1. [10]
    Further, it is said that, in part, the difficulties created by the 2015 works are exacerbated because of inadequate subsoil drainage associated with the retaining wall.  It is said that it has low spots and to some extent seeks to discharge uphill, as well as being broken and blocked.   
  2. [11]
    As to the 2018 works, the applicants allege the following matters taking place in or about August or September 2018 led to more serious difficulties for them:[7]

“In about August or September 2018, the respondents undertook further works to their property.  This included:

  1. (a)
    Importing 60 cubic metres of soil onto the respondents’ property.  This additional soil was used to:
  1. (i)
    Level out the respondents’ land between the top of the slope above the retaining wall, and the respondents’ house;
  1. (ii)
    Extending (sic) the level area of the respondents’ yard out towards the boundary with the applicants’ property; and
  1. (iii)
    Increasing (sic) the steepness of the slope leading down to the top of the retaining wall;
  1. (b)
    This also removed the [effluent] bund[8] that run (sic) along the top of the slope leading down toward the retaining wall;
  1. (c)
    The added soil was topsoil and darker in colour.  The respondents also planted grass seed in this new soil.
  1. [12]
    Following the 2015 works and the later construction of the respondents’ house, the applicants purchased their property on 30 June 2017. The 2018 works took place after the applicants had moved in.
  2. [13]
    The applicants describe that following the 2018 works their property was inundated in a way which had not occurred prior to those works. A substantial amount of soil, mud, sand and grass seed washed down from the respondents’ property around a shed (“the shed”) and breezeway between the shed and the house.
  3. [14]
    Following these events, the respondents caused further works to be undertaken on their property as follows:[9]

“In the period [between] January and February 2019, the respondents caused further works to be undertaken on their property, it is to be inferred, to address the risk of further inundation like that in October 2018.  That work comprised:

  1. (a)
    Constructing an extension to the retaining wall, to construct a further 12 to 14 metres towards the rear of the property;
  1. (b)
    Laying hessian and shade cloth along the exposed ground on the slope;
  1. (c)
    Adding foam blocks into the exposed slope;
  1. (d)
    Adding some additional soil to the top of the retaining wall; and
  1. (e)
    Moving the effluent treatment catchment area from on the land between the respondents’ house and the boundary with the applicant’s property and relocating it to the rear of the respondents’ property.”
  1. [15]
    The applicants claim that from October 2018 through to approximately March 2019 there were regular occurrences of the kind they had seen during the 2018 inundation.  The respondents dispute this. The applicants proposed remedial steps that might be taken by the respondents by a letter dated 26 February 2019,[10] which comprised a concrete spoon drain along the top of the retaining wall.
  2. [16]
    Following this, the applicants took steps (“the applicants’ works”) on their property to minimise the effects of runoff from the respondents’ higher property. Firstly, in May 2019 (“the applicants’ May 2019 works”), they constructed a blockwork retaining wall around the breezeway and shed and modified the cut-batter slope that had existed from the south of the shed towards the boundary with the respondents’ property. They added topsoil to the modified cut-batter slope and planted it out. Having, as the applicants describe it, addressed that most concerning issue of sediment inundation, in 2021 the applicants caused a drain to be constructed on their property below the retaining wall and directed to an attractive catchment pond situated at the front of their property which also serves to take overflow from their rainwater tanks, which previously simply discharged onto the ground (“the applicants’ 2021 works”). The effect is to divert water which passes through, under or over the retaining wall towards the pond.  The overflow from the applicants’ water tanks is also directed to the pond rather than being allowed to overflow into their yard. 
  3. [17]
    All of the “water” experts in the matter accept that the applicants’ works are generally consistent with good building practice so as to direct storm water runoff from upstream catchments away from the applicants’ foundations and thresholds of dwellings.  They refer to them being generally consistent with the requirements of drawing DD1 which is contained in Appendix 5 of the Site Investigation & Footing / Slab Design report – Lot 7 Fernhill Place Diddillibah (that is, the applicants’ property) authored by Donald Stanfield of EBIS (“2013 EBIS report”) and dated 17 July 2013 which contained requirements for shaping and drainage directing water flow away from buildings where a cut-batter is employed.[11]  They also refer to the previously existing cut-off bund as being generally consistent with this drawing.
  4. [18]
    Their effluent discharge area was also relocated from adjacent the water tanks in the front southwest part of their yard.
  5. [19]
    All of these works were in my view sensible precautionary steps for a downhill neighbour to take particularly given the manner in which the building platform had been created so as to leave a very close by slope up to the higher boundary, with no attempt to divert water travelling towards the buildings.  They should have been integrated when the property was developed.  The property without these measures was particularly vulnerable to runoff. 
  6. [20]
    It is the applicants’ position that notwithstanding the applicants’ works, prolonged releases after rain events continue to cause erosion particularly in the immediate areas where the concentrated flows discharge, which appears to be a reference to under the retaining wall, including adjacent the footings.  The respondents’ position is that the erosion at the footings is caused by the applicants’ works, including overflow travelling rapidly past and parallel to the retaining wall.  It is clear to me from videos that in very heavy rain water travels over, through and under the retaining wall. 
  7. [21]
    The applicants claim a mandatory injunction requiring the removal and reconstruction of the retaining wall as well as damages consisting of the expenses associated with the applicants’ works and some other turf replacement.
  8. [22]
    As I have mentioned, despite the applicants’ claim being put on the basis of a change between natural flow and the flow after all of the works had been undertaken on the respondents’ land, there was no analysis initially by Mr Anderson as to what the natural flow would have been.  However, in re-examination he made clear that his views expressed in his reports were not altered by comparing the current features to the natural state rather than to a point part way through the development of the land with a lesser catchment. 
  9. [23]
    The applicants did not own their property prior to development of the respondents’ property, including installation of the retaining wall and placing of the associated fill in 2015 which is said to have detrimentally altered the flow.  All that is known of the natural flow prior to that time is that it was sufficient that it led the applicants’ predecessor in title to construct the cut-off bund above the cut-batter slope over which it has been said the inundation[12] took place in this matter.  In some respects this fact that the natural flow was such as to require this is a difficult starting position for a claim which depends on showing the natural flow was interfered with by the respondents so as to create a nuisance.  It is clear that, at least in very general terms, overland flow seems to have been some kind of difficulty before any works were undertaken on the respondents’ property.  But it is critically important to recognise that the applicants’ case is put on the basis that these works concentrated the flow from what would have been the position had there not been an object such as the retaining wall placed across the path of the natural flow and their expert evidence was that the result was worse than the natural flow would have been because of this feature. 
  10. [24]
    The existence of a problem previously is perhaps somewhat unsurprising given the topography and the method employed by the applicants’ predecessor in title to create a level building platform.  The respondents’ property is significantly above the applicants’ property.  The creation of a cut-batter slope on that lower property with little or no vegetation adjacent to the boundary with the respondents’ higher land without functional drainage around the bottom of the cut-batter to direct the overland flow (rather than subsoil water) away from the applicants’ buildings or a bund at the top of the cut-batter does not seem to constitute good building practice particularly having regard to the scope for receipt of overland flow.  It is not immediately obvious why a higher neighbouring owner would be obliged to take steps to avoid those risks which are just the function of the adjacent block of land being higher.   
  11. [25]
    Having said what I have about natural flow, the applicants’ case is put on the basis that the 2015 works and/or the 2018 works concentrated the flow from what would have been the position had there not been an object such as the retaining wall placed across the path of the natural flow.  Their case is not about volume but instead concentration and velocity.  It is put that the respondents’ act in placing the fill and installing the retaining wall without effective drainage was such as to alter the arrangement of the land in a way which increased the concentration and/or velocity at particular points on the boundary rather than increasing the volume of flow overall which it is accepted had been reduced by the building of the house and construction of the flat area.
  12. [26]
    I deal with the expert evidence as to stormwater drainage and groundwater hydrogeology below.   

Structural and design elements

  1. [27]
    The applicants also complain as to the structure or condition of the wall in that:
    1. (a)
      the footings are not deep enough and are thus inadequate;
    2. (b)
      there is insufficient sub-soil drainage behind the retaining wall (as required by section of Volume 2 of the Building Code of Australia);
    3. (c)
      the ag-pipe does not have appropriate fall and is both broken and blocked;
    4. (d)
      the footings encroach into the applicants’ property;
    5. (e)
      the posts have begun to lean forward because the footings are not deep enough to sustain the load on the wall;
    6. (f)
      the soil at the base of the footing on the applicants’ property and below the timber sleepers has eroded, causing the concrete footings to be exposed.  
  2. [28]
    The respondents’ position is that when the applicants’ property was developed by its then owner, Mr Gould, a builder, he caused the cut resulting in the cut-batter slope adjacent to the shed and breezeway to be made to achieve a flat building platform on this lower land and constructed a bund on the respondents’ land (without permission) immediately above the cut-batter slope, presumably to alter the natural overland flow.  As I have said I would be prepared to draw an inference that that was to deal with a run-off problem although I accept immediately that there is no evidence as to precisely what that problem was.
  3. [29]

“… the works undertaken by the Respondents on their property, which includes the construction of the dwelling, pool, retaining walls around the dwelling, installation of water tanks and other improvements and associated drainage:[13]

  1. (a)
    is a reasonable and natural use of their land;
  1. (b)
    has in fact reduced the natural overland flow of stormwater such that:
  1. (i)
    the change to water flow at the boundary is an improvement on the natural state;
  1. (ii)
    the change to water flow does not create an actionable nuisance;
  1. (c)
    the retaining wall is structurally sound, and constructed appropriately. There is little in the Applicants’ case to explain why the structural integrity of the wall is in issue, particularly as the integrity of the wall has no bearing on the alleged change to water flow at the boundary.”
  1. [30]
    As will become apparent, this aspect is the key to the resolution of this matter.
  2. [31]
    In terms of the inundation itself, the respondents’ position is that the flow referred to by the applicants only occurs only in extreme events and is what one would expect from natural overland flow. There has been a reduction in the flow by reference to what the position would have been had the respondents’ property not been developed.  In part, importantly, this relies on the allegation that the water is captured by the ag-pipe at the base of the retaining wall and conveyed to the road reserve, with only part of it left to pass through or under the wall.  The respondents say that there has been no increase in volume, velocity or duration of the water flow.  Instead, there has been an overall improvement.  The ag-pipe is a fundamental element of this.  It was dealt with in some detail in the respondents’ experts reports including by attaching the plans approved for the wall which showed the presence of an ag-pipe with a sock over it and a fall to discharge point.   Its collection and conveying of the water away from the boundary is a clearly fundamental part of the overall reduction in volume that the respondents experts refer to including in the joint report.  The cross-examination of Mr Anderson proceeded on the basis that the ag-pipe was of course not designed to convey every drop to the point of discharge.[14] There was never any suggestion in his cross examination that the pipe was not meant to flow to a point of discharge.  The cross-examination came before most of the flaws in the pipe were known, although exhibit 3 suggests the respondents knew of at least some of them in September last year but gave no instructions to their experts as to this important matter (given the focus on the drainage at the wall), expect for Mr Rienecker who gave the extraordinary evidence that it was irrelevant.  I do not accept this evidence.  I generally prefer the evidence of Mr Stanfield to Mr Rienecker.
  3. [32]
    After it became clear the pipe went up and down, was broken, blocked and had no sock on it, Mr Thomson and Mr Rienecker sought to give frankly remarkable evidence that it was not needed, was not part of the intended design for this wall, that other retaining walls are built without such pipes all the time and effectively the water was all intended to travel through the wall and not to a lawful point of discharge.  That was a particularly unconvincing display.  I was left with real concern as to whether they had forgotten the effect of rule 429F(2)(a) of the UCPR and become an advocate for the respondents.  I was concerned as to Mr Thomson’s evidence and prefer Mr Anderson’s evidence and Mr Unsworth’s evidence to the extent of any inconsistency.  Further, as to this issue, Mr Thompson had earlier confirmed that the intent of the drain was in fact for water to flow out of the ends and away to the verge.[15]  The other point to be made about what Mr Rienecker says is whether or not the wall structurally needed a lawful point of discharge and fall on the ag-pipe does not answer what the absence of this may do by way of conveying water across the boundary creating a nuisance nearby.
  4. [33]
    With respect to the structure, the respondents say that:
    1. (a)
      there is unintentional encroachment of 6 concrete footings; and
    2. (b)
      the retaining wall is not defective because of the installation of the tie-backs after construction and the sub-surface drainage at the time of the construction.

Relevant principles

  1. [34]
    In the leading High Court case, Gartner v Kidman,[16] Windeyer J, with whom Dixon CJ agreed, said:[17]

“With the above limitations in mind, the rights and obligations of the proprietors of contiguous closes, one on a higher level than the other, may be stated as follows:—

The higher proprietor: He is not liable merely because surface water flows naturally from his land on to lower land.

He may be liable if such water is caused to flow in a more concentrated form than it naturally would.

It 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.

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.

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.

The above statements concerning the concentration of surface waters relate to cases when the increased flow results from work done when the higher land and the lower land were 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.

The lower proprietor: He 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.”

  1. [35]
    In Corbett v Pallas,[18] Priestley JA (with whose reasons Mahoney JA generally agreed and Meagher JA agreed) said:[19]

“I simply rely on the reasons given in the three decisions[20] for the following propositions, the first four of which adapt what Burbury CJ said in Kraemers (at 118) and the fifth what Windeyer J said in Gartner (at 48):

  1. 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.
  1. The plaintiff does not have to prove unnatural or unreasonable use of the land by the defendant.
  1. 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.
  1. 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.
  1. Whether a particular use of land is “natural” must be determine 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.”
  1. [36]
    Also, Mahoney JA and Priestley JA each considered whether the swimming pool constructed without appropriate drainage could be a natural use or escape liability for nuisance on such a basis.  As to this, Mahoney JA said:[21]

“…it resulted from the way in which the particular swimming pool was constructed.

This is relevant not to establish, as such, that the work was done negligently.  The case was pursued in nuisance and not in negligence. But it is relevant in determining whether what occurred was a nuisance: see generally Gartner v Kidman (1962) 108 CLR 12 at 48. It has been said that there is no liability in nuisance where the use made of the land is not an unnatural use or an unreasonable use of it. It is not, for the purposes of this appeal, necessary to conclude that the erection of a swimming pool of this kind in the backyard of suburban premises is a non-natural or unreasonable use of such land. But where the swimming pool is erected in such a way as to concentrate the flow of water as this did and there are other ways of constructing it, liability is not to be avoided upon the ground that what was done is, in whatever sense, a natural user of the land or a reasonable use of it.”

  1. [37]
    Priestley JA said:[22]

“Sinclair DCJ's finding that the construction of the swimming pool by Mrs Corbett was a natural use of the land but that the consequential diversion and concentration of the flow of water on to Mr PalIas's land was unreasonable has an element of inconsistency in it, but read in the context of his factual findings and reasoning generally seems to me to have been in substance intended to convey that the construction of the swimming pool without appropriate drainage was not a "natural and reasonable" user of the land in the sense used by Burbury CJ nor in the sense used by Windeyer J, a natural user of the land, in that looking at it reasonably in the circumstances, including the purposes for which the land was being used and the manner in which the flow of water was increased, the user could not be said to be natural.”

  1. [38]
    Similarly as to what is a natural use, in State of Queensland v Baker Superannuation Fund Pty Ltd [2019] 2 Qd R 146 McMurdo JA with whom Morrison JA agreed said at [199]:

Windeyer J there referred to the “natural” use of land by the higher proprietor, a term which he had explained earlier in his judgment as follows:

It seems appropriate to observe here that the notion of a natural use of land, and the distinction between a natural and a non- natural use seems to have come into the law at this point from Lord Cairns’ judgment in Rylands v Fletcher: see the article by Professor Newark in 24 Modern Law Review, 557. The concept involved is a difficult one; and in formulations of the law of nuisance it may be better to start with what Bramwell B. said in Bamford v Turnley, that ‘acts necessary for the common and ordinary use and occupation of land and houses may be done, if conveniently done, without subjecting those who do them to an action’. By ‘conveniently done’ the learned Baron meant, no doubt, done in a reasonable and proper manner. He contrasted such user with a use ‘not unnatural nor unusual, but not the common and ordinary use of land’. However, the expression ‘natural use’ has come to be much used in discussions of this topic, and I have adopted it later in this judgment.”

(Footnotes omitted.)

  1. [39]
    As to concentration of flows, in Gales Holdings Pty Ltd v Tweed Shire Council[23], Emmett JA, with whom Leeming JA and Sackville AJA, relevantly, agreed, said:

“[135] Where there are two contiguous parcels of land and one is higher than the other, the higher proprietor is not liable merely because surface water flows naturally from its land to the lower land. Surface waters, while distinct from natural watercourses, are those that flow naturally onto land, as distinct from water artificially brought to or concentrated on land and allowed to escape. The higher proprietor may be liable if surface waters are caused to flow onto the lower land in a more concentrated form than they naturally would. An example would be if a water channel were constructed and the levels or conformations of the higher land altered, so as to cause the flow of surface waters onto the lower land to be increased at any particular point. On the other hand, if a more concentrated flow occurs simply as a result of the higher proprietor’s natural use of its land, generally there will be no nuisance. Whether a use is natural is determined in the light of all of the circumstances, including the purposes for which the higher land has been used and the manner in which the flow of water is increased (Gartner v Kidman at 48).”[24]

A chronology of relevant changes to land of the parties

  1. [40]
    A brief chronology of relevant events is as follows:[25]



During 2013

Mr Gould (the applicants’ predecessor in title) digs a trench / cut-off bund on the respondents’ property without any right to do so


Construction of dwelling and shed on the applicants’ property

27 August 2013

Respondents’ purchase their property

September 2015

Construction of the retaining wall.  The cut-off bund is removed as part of this

June 2015-2016

Construction of house on the respondents’ property including earthworks

Early 2016

Earthworks to “shape and groom” flat yard area

Jan-Feb 2016

Installation of initial nine tie-backs to retaining wall

30 June 2017

Applicants purchase their property

September 2018

Respondents install irrigation system, including spraying grass, addition of 60m3 topsoil and seed. 

The effluent bund was removed as part of these works.

9-12 October 2018

Inundation alleged by Applicants

17 February 2019

Extension to retaining wall constructed

May 2019

Respondents move effluent disposal area.

Additional 20m3 topsoil applied to respondents’ property to provide cover for relocated effluent disposal area

May – June 2019

Applicants conduct earthworks and construct block wall at base of cut-batter slope

May 2021

Earthworks on applicants’ property creating drainage to retention pond

Sep 2021

Development approval for earthworks and retaining wall

October 2021

Additional tie-backs installed

The evidence

The applicants’ lay witnesses

  1. [41]
    Dr Graham gave evidence to the following effect:
    1. (a)
      Between when he and Dr Sunderland first moved into the property in mid-2017 and about September 2018, some water and soil would run onto the slab near the shed during larger rainfall events but it was not a major issue;[26]
    2. (b)
      At the time they moved in, there was a relatively consistent upwards slope from the retaining wall to the respondents’ house which was more pronounced to the east of the respondents’ property.  During cross-examination it became clear that Dr Graham had not studied the topography of the respondents’ property in any detailed way prior to the alleged inundation in October 2018 and was thus not able to say much about changes;[27] 
    3. (c)
      In 2018, the respondents performed work to their property between the retaining wall and the house. This included adding soil to create a steep slope towards the applicants’ property about 1.5 to 2 meters high which was exposed and had no vegetation.[28]  In cross-examination he confirmed he understood that Dr Alic’s version of events was that there was only 60 cubic metres of topsoil added.  As I have mentioned, apart from identifying the difference in his experience of runoff from about September 2018, in my view he was not able to reliably explain any observed changes in topography;
    4. (d)
      Since the 2018 works, every time it would rain the house, yard, breezeway and studio would be inundated with water and mud. He said that he knew it was the respondents’ soil as it was a mix of sandy soil and darker muddy soil;[29]
    5. (e)
      In January 2019, the respondents attempted to remediate some of the erosion and overland flow by using netting, foam and shade cloth but these measures did not work and the problems continued;[30]
    6. (f)
      In early 2019, he observed that the retaining wall began to deteriorate including posts shifting, posts rotting and water flowing under the wall.[31] He observed that this was still the case in December 2021.[32]  It should also be noted that it is otherwise clear from Mr Rienecker’s evidence and that of Mr Alic that there were structural issues in early 2016 about 4 months after the wall was built and then again in October 2021, 3 months after the wall had been said by Mr Rienecker to be structurally sound, and one month after the retrospective approval was granted;
    7. (g)
      After a large rain event occurring around Easter 2019, the water flow created a number of large channels in the soil on the applicants’ property. These were at least 10cm deep;[33]
    8. (h)
      In April 2019, the applicants had a retaining wall built around the slab and the shed. No soil has washed onto the slab since the works were completed;[34]
    9. (i)
      In June 2019, grass begin to establish on top of the respondents’ retaining wall and since then soil runoff from over the top of the retaining wall has been less frequent.  Water has now been observed coming through channels under the wall which has caused erosion in the soil at the footings and base of the retaining wall;[35]
    10. (j)
      After rainfall events from March 2021 to December 2021, water has continued to flow under the retaining wall, and on one occasion washed away soil that covered the footings of the wall;
    11. (k)
      On or about 22 February 2022, he observed that a number of previously exposed concrete footings had soil covering them. After another rain event at the end of February, this new soil had eroded from the footings and they were again exposed;[36]
    12. (l)
      He took a number of videos of water on 25 February 2022 after it had been raining and he observed water flowing through and under the retaining wall;[37]
    13. (m)
      On 7 March 2022, he observed Dr Alic spreading hay mulch across the slope covering up the exposed soil and foam blocks;
    14. (n)
      Water continues to seep out from under the retaining wall after rainfall events for 3 to 5 days which is longer than it in had in August-September 2018.[38]
  2. [42]
    Dr Sunderland gave evidence to the following effect:
    1. (a)
      She observed the respondents added large amounts of soil in or about August or September 2018 to their property between their (that is, the respondents’) house and the retaining wall. Those works left a large amount of dark soil exposed with no vegetation;[39]
    2. (b)
      She observed the respondents sowed grass seeds on the soil in October 2018;[40]
    3. (c)
      A few weeks after the 2018 works and after a substantial rain event, she observed a substantial amount of soil and grass seed from the respondents’ property washed onto her driveway, breezeway and the concrete slab outside of the shed. They had not experienced this before;[41]
    4. (d)
      When the respondents added the extension to the retaining wall between January and February 2019, she also observed that the respondents added shade cloth material to the exposed soil slope, hessian netting over the topsoil and put large foam blocks in the soil;[42]
    5. (e)
      After these works were done sand and mud would continue to come down onto the slab when there was heavy rain;[43]
    6. (f)
      In May 2019, the applicants had a retaining wall constructed around the shed. Since that has been done, there has been no further inundation of soil;[44]
    7. (g)
      Water continues to flow over, through and under certain parts of the respondents’ wall;[45]
    8. (h)
      During a rainfall event in June 2019, she observed water flowing down the respondents’ property , pooling at the top of the retaining wall and flowing over and under the wall in certain areas;[46]
    9. (i)
      On 25 February 2022, 12 hours after a rain event started, she observed that the ag-pipe had no water coming out of the end of it, and there was water coming over and under the wall.[47]
    10. (j)
      On 10 April 2022, she observed a break in the ag-pipe between the 8th and 9th posts from the front of the property.[48]
  3. [43]
    I found both lay witnesses for the applicants to be doing their best to recall the events relevant to the matter.  While they were not really able to describe in any detail any changes to the respondents’ land over time, that was not of any particular significance given the expert evidence and the useful plan prepared by Dr Alic to which I have already referred.  The applicants were able to clearly explain that the amount of water received across the boundary in the location of their buildings changed significantly in October 2018.  I accept their evidence as to this change. 
  4. [44]
    While I do not consider that the addition of 60 cubic metres of topsoil alone can have had the effect described, it seems likely to me that the combination of this loose soil on the respondents’ land together with the removal of the bund at the same time, the slight increase of the slope on the battered slope above the wall as well as the defective nature of the ag-pipe were sufficient to cause an increase in the amount of water confronting the applicants as well as making it starkly more apparent, because of the topsoil and seed.  It may be that the effluent bund, to that point, had been sufficient to prevent what the applicants later experienced.  It may also be that the change in slope was a factor with the bund removal.

The respondents’ lay witness

  1. [45]
    Dr Alic gave evidence to the effect that:
    1. (a)
      On an unknown date in 2013 Mr Gould built a trench on the respondents’ property near the boundary with the applicants’ property. This was before Mr Alic undertook works on his property and he did not give Mr Gould permission to do this;[49]
    2. (b)
      The trench interfered with the flow of stormwater as it stopped the natural downhill flow onto the applicants’ property. Mr Gould told Mr Alic that it was to stop his property from flooding.[50]  As I have mentioned, I am prepared to infer in relation to this that the purpose of it was to minimise run-off.   What is not known is the precise extent of that issue compared to that experienced by the applicants following October 2018;
    3. (c)
      Between 2015 and 2018, the slope that led down to the shed and house on the applicants’ property was not retained or vegetated;
    4. (d)
      He caused the construction of a retaining wall in late 2015, but he did not have approval at the time it was built.  He said that he was mistaken, thinking at the time that it was part of the development and part of the certification of the other retaining walls.[51] He has since sought approval;
    5. (e)
      He acknowledges that after the topsoil and grass seed were added to the property in September 2018 and that there was a large rain event between 9 to 12 October and that Dr Sunderland informed him that seeds and topsoil transferred onto her property during the rain event;[52]
    6. (f)
      On 14 October 2018, a heavy rain event occurred. He observed that there was some water seeping through the eastern end of the wall, there was no silt or seed coming around the retaining wall, there was a small amount of water flowing down the hill and that there was no water coming over or through the retaining wall;[53]
    7. (g)
      He disagrees with Dr Graham who said in his third affidavit that soil would wash down from his property onto the shed slab almost every two weeks between October 2018 and April 2019;[54]
    8. (h)
      He became aware that a complaint had been received by the Council in February 2019 about the earthworks that occurred on his property;[55]
    9. (i)
      In around May 2021, he was aware that the applicants carried out significant earthworks on their property which appear to capture water from the northeast slope of their property;
    10. (j)
      On 21 March 2021 (which he describes as a rain event), 22 March 2021 (which he describes extreme rain event) and 5 April 2021 (which he describes rain event) he observed that there was no water flowing over, though or under the retaining wall.[56] Video footage of both occasions is taken from the front boundary of the applicants’ property. The video taken on 21 March 2021 only shows a relatively small part of the retaining wall which is closest to the road. The 22 March video is a view directly along the retaining wall from the front boundary. While there does not seem to be water cascading over the wall, it is very difficult to tell what is otherwise occurring in terms of water.  In circumstances where we know that the ag-pipe is not working, including because of its lack of fall, it would be quite surprising if there was not water coming through and under the wall;
    11. (k)
      The rainfall experienced on or about 25 February 2022 Dr Alic refers to as an extreme rainfall event.  He understands that water may flow over, through or under the retaining wall during such events. He did not agree with Dr Graham’s suggestion that it was common after rain;[57]
    12. (l)
      The effluent bund had experienced erosion.  It was reduced in size in 2018.  The slope below it was increased slightly in steepness.
  2. [46]
    I found Dr Alic to be doing his best to reliably give evidence as to what he observed. Having said that, I consider that the applicants were in a significantly better position to have observed water travelling onto their block and to discuss its effects. I also query Dr Alic’s evidence to the effect that he recites in various places that no water travels out from underneath the retaining wall which in my view is completely inconsistent with the state of the ag-pipe.

The expert evidence

Stormwater drainage and groundwater hydrogeology

  1. [47]
    The applicants rely on three reports of Christopher Anderson dated 16 March 2021, 20 July 2021 and 10 March 2022. The respondents rely on two reports of Brett Thomson dated 20 May 2021 and 22 October 2021 and a report of Ian Unsworth dated 3 November 2021.
  2. [48]
    In addition, each of these experts participated in a joint site inspection meeting on 31 January 2022 and subsequent email and telephone calls and produced a joint report dated 18 February 2022 (the Stormwater Drainage Joint Report).
  3. [49]
    It is convenient to focus attention upon the contents of the Stormwater Drainage Joint Report, especially given the extent of agreement between the experts.
  4. [50]
    During 2013, the cut-batter slope being a three metre deep cut batter was created around the southern and eastern ends of the shed to facilitate a flat building pad for it. They described the cut-batter as relatively steep and composed of exposed subsoils without topsoil, vegetation or other types of ground cover. They also describe the effect of the cut-off bund being installed in about November 2013 along the boundary with the applicants’ land but generally located on the respondents’ land by the previous owner/builder of the applicants’ land. They agree that the cut-off bund would have intercepted and diverted and therefore reduced the natural surface stormwater flows from the respondents’ property to the applicants’ property as occurred prior to the respondents constructing their house and associated works. They agree that the functionality of the cut-off bund maybe considered as being generally consistent with the intent of the requirements of drawing DD1 included in Appendix 5 of the Site Investigation & Footing/Slab Design Report – Lot 7(number 26) Fernhill Place, Diddillibah by EBIS dated 17 July 2013[58] as relevant to diverting stormwater away from the buildings on the applicants’ land.
  5. [51]
    As part of the construction of the respondents’ house, pool and associated works, the cut-off bund was removed and in September 2015 an approximately 40 metre long section of retaining wall was constructed.
  6. [52]
    The experts agree that the construction of the respondents’ house and hard stand areas with runoff diverted to the road reserve to the west and to the environmental covenant area to the east had the effect of reducing the quantity and velocity of rainfall runoff discharges from the respondents’ property which may have otherwise been directed towards the applicants’ land.
  7. [53]
    The experts agree that during 2016 the slope on the respondents’ land between the respondents’ house and the boundary with the applicants’ land was significantly reduced due to the filling and installation of the retaining wall.
  8. [54]
    It is agreed in the joint report that there is evidence of the installation of a subsoil drainage pipe behind the original part of the wall.  Although, as became apparent, it was not properly installed, had no sock on it, did not have appropriate fall on it and has now become blocked and broken.
  9. [55]
    It is agreed that aerial photographs show that the cut-batter slope had no vegetation cover and was subject to erosion, including during the October 2018 inundation. The experts agree that the relocation by the respondents of their effluent disposal area to the north east of their property and the spreading of topsoil to the former effluent disposal area had the effect of further reducing the slope of that area and causing stormwater runoff to be of lower velocity and allowing additional infiltration.
  10. [56]
    The experts also agreed on a number of matters relevant to the 2018 inundation. First, that there were a number of significant rainfall events that may have been associated with the inundation. Secondly, that, as I have already mentioned, the historical photographic evidence demonstrates that the top of the cut-batter slope was not protected by a stormwater diversion at the relevant time (although as I have mentioned, it was earlier), and nor were there effective erosion controls over the surface of the cut slope soils. That meant that any runoff from the respondents’ land joined with that from the applicants’ land and flowed down the cut-batter slope causing erosion and sediment laden water to impact the patio area.
  11. [57]
    The experts agree that the applicants’ May 2019 works were consistent with good building practice so as to direct the stormwater runoff from upstream catchments away from the applicants’ foundations and thresholds of dwellings. I have already noted that the 2019 works are generally consistent with drawing DD1.
  12. [58]
    The experts agree that the relocation of the respondents’ EDA in May 2019 meant that a possible cause of ground saturation in the vicinity of the boundary with the applicants’ property was removed from around that time. It is relevant also in this respect to note that the experts agree that part of the effect of the effluent bund (which was situated downstream from the respondents’ EDA up to September 2018) was to cause some ponding upstream of that bund on the respondents’ land and thus saturation.
  13. [59]
    Further, the applicants’ EDA had been located in an area immediately to the north of the boundary (towards the west of the applicants’ property), but after the applicants’ 2021 works it was relocated to the east of the applicants’ house where potential adverse effects on ground saturation would impact on the vegetation covenant area rather than the applicants’ land. The experts express the view that the applicants’ EDA may have caused the ground to be saturated from a combination of rainfall and application of treated effluent, particularly because no bunding was apparent either upstream or downstream of that area. Accordingly, saturation of soils on or below the EDA on the applicants’ land is likely to have contributed to stormwater runoff discharges across the applicants’ EDA including during the 2018 inundation.
  14. [60]
    As to the filling of the respondents’ land, the experts agree that this has increased the volume of soil that could hold water and that increased volume has a higher porosity than the original soil.  Both factors result in less opportunity for rainfall on the fill area to report as runoff (towards or on to the applicants’ land). The lessening of the slope on the respondents’ land allows for more rainfall infiltration rather than runoff. The fill will tend to hold water and release it over a longer period at a lower velocity. Thus, the potential for erosion would be reduced but the duration of runoff maybe increased.
  15. [61]
    The experts agree that the diversion works on the applicants’ land, as observed during the site inspection, were considered to be adequate to direct surface and seepage flows away from the applicants' house and granny flat, to the applicants’ new pond system which overflows to the street.  They agree that had such a system been installed at the time of the 2018 inundation the opportunity for runoff from upstream catchments to enter the granny flat area would have been mitigated.
  16. [62]
    The experts disagree about the requirements set out in the Core Consulting Slope Stability Assessment (“the Core Consulting Report”) which was a document provided to the council in respect of the retrospective application for approval . There is disagreement amongst the experts as to whether nor not some of the requirements for a spoon drain or a bund are requirements other than on a temporary basis. For reasons that will become apparent shortly, there is no reason for me to resolve this issue.
  17. [63]
    Mr Anderson, in the joint report, maintained that some sort of diversion above the retaining wall together with reduction of fill, which is something referred to in the Core Consulting Slope Stability Report, was necessary. In his third report dated 10 March 2022, he expresses the view that the outlet of the ag-pipe is 400 millimetres higher than its lowest point with the obvious consequence that flow is likely to be restricted at best.  As I have mentioned, it became clear this was one on many flaws in the ag-pipe. 
  18. [64]
    Specifically, as to the drainage pipe, the respondents’ experts say that there is no evidence of a defined seepage zone such as wet spots caused by low areas of the pipe along the wall. It is said that there is no evidence that the subsoil drain does not flow.[59]  Of course, now there is good evidence that it does not given the evidence of Mr Brailsford and Mr Stanfield.  I prefer this direct evidence rather than that of the respondents’ experts which seeks to draw inferences from imprecise but observable site conditions rather than to directly address the function and condition of the ag-pipe. I accept that the ag-pipe is defective in the respects I have identified above.  I do not accept the respondents’ experts evidence in this respect.  As I have said above I thought Mr Thomson’s evidence on this topic reflected poorly upon him.
  19. [65]
    Mr Anderson is of the view that the removal of the bund and associated earthworks in 2018 changed the stormwater flow characteristics such that stormwater flowed where it had not previously, that is, below that bund. The respondents’ experts disagree as to this, but, of some significance, they do not entirely disagree. They say that there was a raised lip along the boundary which, while it may not have been equal in the effectiveness of the effluent bund (because it was lower in profile), it would have the same functionality. In other words, it seems clear that all accept that the effluent bund had a positive effect as to reducing runoff across the boundary but it is also said that its effect was not completely lost with its removal.  That seems to me to accept that a positive effect in this respect was lost.  Otherwise, the respondents’ experts maintain that the improvements on the respondents’ land have reduced the quantity and velocity of stormwater although they do not divert 100 percent of it. In addition, they express the view that the effluent bund may not have had an effective outlet so it simply caused ponding such that with the amount of rainfall in October 2018 it may have simply overflowed had it still been there. Mr Anderson gave evidence that it fell towards to road such that it diverted runoff.[60] 
  20. [66]
    I prefer Mr Anderson’s evidence as to these matters.  In any case, in cross-examination, Mr Thompson agreed that that could have been a contributing cause to the inundation to the applicant’s property that occurred shortly after.[61]
  21. [67]
       Finally, there is disagreement between the experts as to the relevant time at which a comparison should be made between the predeveloped condition of the respondents’ land and its current condition. The respondents’ experts proceed on the basis that the appropriate consideration is between the land as it naturally existed prior to any development and in its developed state including construction of the house, pool, hard stand areas with drainage to the street, water tanks and the fill as well as the retaining wall. The applicants’ expert considers that the appropriate time is after the respondents had built their house but before they undertook filling works and wall construction. That appears to be said to be the case on the basis that the works for the construction of the house were approved while the wall was not.
  22. [68]
    I must say in relation to that, it does seem to have some artificiality in it. But it seems to me that that is not the end of the question. While the experts agree that the catchment available has been reduced, it remains to consider what might occur with the addition of the retaining wall (even with the reduced catchment) having regard especially to what appears from other evidence to be the defective design and condition of the ag-pipe.
  23. [69]
    Despite the optimism of the respondents’ experts as to the state, and functionality, of the ag-pipe, it appears that it is blocked, broken and, according to the unchallenged evidence of Mr Stanfield, a design failure.  Not only does that obviously allow the water it should covey towards the road to pour through the retaining wall and into the applicants’ property, it also means that the council condition requiring that the construction comply with the approved plans is not satisfied because Mr Rienecker’s plan showing a sock covered ag-pipe with a fall has not been built.  As I have mentioned, I do not consider it necessary to make any finding as to whether or not there was another failure to comply with the development approval being the alleged failure to comply with the requirements of the Core Consulting Report, and that is simply because I consider that there is a clear enough breach of the development approval in respect of the instillation of the ag-pipe.
  24. [70]
    During cross examination, Mr Anderson explained that the purpose of his third report was to address changes in the catchment over time due to the existence of the bund adjacent the respondent’s effluent disposal area and its removal. He was also asked about a video (NS8) showing water ponding at the top of the retaining wall, cascading down the front of it and then water coming from behind the wall at its base. In relation to that water discharging underneath, he said that that demonstrated, in his view, that the ag-pipe was not discharging correctly.  The evidence is now clear as to why this might be.
  25. [71]
    As to the change in catchments, Mr Anderson said that he took the view in his first report that there was no change so the amount of volume was of no consequence and it was actually the mechanisms or characteristics of the flow which were important.[62] He accepted that the position in terms of volume was better with the house and the hardstand built than it was naturally but said that the wall itself being an impermeable structure could actually again concentrate the flow.[63]
  26. [72]
    As to these features, Mr Thomson accepted that an impermeable object placed in a natural sheet flow of water causes that flow to change by increasing the depth and velocity. He also stated that this may have the effect of causing concentrated flows in locations where it flows around the object.[64]  Mr Unsworth also stated that water emerging from a weak spot in the wall may be at a faster velocity than over the ground before the works were done.[65]
  27. [73]
    Mr Anderson was cross-examined about the cut-batter slope and the alleged absence of drainage at the lower side of it.[66]
  28. [74]
    Mr Anderson was cross-examined about the function of an ag-pipe and unsurprisingly accepted that it was not designed to capture every drop of water. As to the 2018 works, Mr Anderson accepted that the spreading of 60 cubic metres over about 3000 square meters would have no effect on water flow.[67] Similarly the 20 cubic metres of soil in the effluent disposal area on the respondents’ land would not affect much.[68]
  29. [75]
    Whilst Mr Anderson had said in his second report that the absence of drainage around the slab on the applicants’ land was not good building practice, he said it was irrelevant to the nuisance. He explained in cross examination that was because the location of the nuisance so far as he was concerned was immediately adjacent the retaining wall.[69]  
  30. [76]
    Mr Anderson was cross-examined  about his two proposals for remediation, one being removing the wall and putting the land back to its pre-existing form and the second being installing a drainage swale upstream of the retaining wall to direct surface water to a lawful point of discharge. Mr Anderson was cross-examined  about whether that was possible having regard to the topography of the land.[70] Mr Anderson was cross-examined in relation to the Core Consulting report.He ultimately expressed the view, perhaps unsurprisingly, that whether or not there was a requirement to comply with that report would not change his view that the wall needed to be free draining. When he was cross-examined  about whether he had undertaken any investigation to determine where or how far along the wall the low point of the drain might be he said one could tell from the contours although he accepted that it did not necessarily follow the wall.[71]  Unfortunately, all this occurred in circumstances where little, compared to what was later known in the case about the condition and installation generally of the ag-pipe, was known.
  31. [77]
    In re-examination, Mr Anderson was taken to the various different catchment plans in Mr Thomson’s report and asked whether the characteristics he was referring to are altered by reference to assumptions as to different catchments and if so in what way. Effectively he confirmed that he considered that the smaller catchment with the retaining wall was worse for the characteristics of depth and velocity, duration and location than the larger catchment[72] without a wall.[73]
  32. [78]
    Mr Anderson was asked about the 2018 works and confirmed that he considered the flattening of the bund down gradient of the effluent disposal area to be critical. As will be recalled that bund was at the bottom of the flat area containing the EDA before it went down the batter and then the retaining wall.[74] The importance of that bund was that the water would build up behind it and then according to Mr Anderson run towards the road so that actual overland flow was prevented at that location.[75]
  33. [79]
    I am satisfied that:
    1. (a)
      The ag-pipe has not been installed in accordance with the approved plans, good practice or the Core Consulting Report to the extent to which it is required to be complied with, and I make no finding as to that.  The reason for this is that the ag-pipe has no sock, it does not fall appropriately and is not free flowing;
    2. (b)
      The ag-pipe is broken and at least partially blocked with sediment that ought not be in it but is because of either or both that there is no sock on it and the geotech fabric has not been properly used to separate the gravel and soil;
    3. (c)
      The water is concentrated at the wall and likely has a higher velocity following its travelling down the adjacent batter before reaching the retaining wall.

Structural elements and appropriateness of construction including ag-pipe

Donald Stanfield

  1. [80]
    Mr Stanfield gave evidence in chief in addition to his reports about the development approval for the retaining wall.[76] He was asked a series of questions about the Core Consulting Report, and how it is that that might form part of the requirements.  Of more significance, he gave evidence, again, in chief, that it would not be economically viable to replace the ag-pipe behind the wall.[77] He was not cross-examined on this issue.
  2. [81]
    Mr Stanfield was cross-examined about the ag-pipe. He accepted that it had been placed above the natural ground level behind the wall.[78] He gave evidence of being able to observe quite a few breakages in the ag-line ag-pipe itself and that he could physically see the line which he should not be able to see.[79] Mr Stanfield then explained that the main deficiency he saw with the wall was that the wall goes up on the end and that is where the point of discharge is for the ag-pipe so that the water would have to go uphill to go to the point of discharge and for that reason it meant that in high rainfall events there was going to be a lot of seepage underneath the wall.[80]
  3. [82]
    Mr Stanfield confirmed that it was his opinion that the wall needed to comply with of the Building Code from 2015 by reason of the provisions of[81] Mr Stanfield gave evidence that it was necessary that the land below the wall be graded with a uniform fall of not less than 1:300 which meant that if it was flat some grade needed to be introduced.[82] The cross-examination proceeded on the basis that the only requirement for such drainage was if the drain was to drain behind the footings which is a reference clearly to the wording of the provision. However, of course, it appears as though the drain was not placed in that way in this circumstance, that is behind the footings. Perhaps the respondent’s case might be best understood as being that the ag-pipe was put there out of an abundance of caution rather than being necessary, but the difficulty with that is that the ag-pipe was placed above the footings, the ag-pipe was specified on Mr Rienecker’s drawing, but it simply wasn’t installed appropriately..
  4. [83]
    Mr Stanfield also gave evidence that he was concerned that the anchor blocks had been placed in uncontrolled fill which he considered inappropriate.[83]
  5. [84]
    In re-examination Mr Stanfield gave evidence that he considered that the site conditions necessary for drainage as set out in of exhibit 6 existed. He gave evidence that there was not a gradient on the ag-pipe installed that met the requirements of

Joint report

  1. [85]
    Mr Stanfield gave two reports on behalf of the applicants dated 26 September 2021 and 19 January 2022. Peter Rienecker gave a report dated 29 September 2021 on behalf of the respondent. In addition, they gave a joint report dated 31 March 2022.
  2. [86]
    The joint report firstly deals with Rienmac drawing 14 301-s14A. That drawing is part of appendix D to Mr Rienecker’s report dated 29 September 2021. In the joint report it is recorded that the wall was not constructed in accordance with that drawing. The focus there was because the footings were not sufficient. However, given other evidence in the matter it is also clear that the construction does not comply because it was to contain an ag-pipe drain wrapped in geofabric sock with a fall to outlet. There was no sock and as is otherwise apparent, the fall is inappropriate.
  3. [87]
    The experts disagree as to whether the tiebacks recommended by Mr Rienecker’s and installed are sufficient to render the wall structurally sound. Mr Rienecker considers that the fill material in which the blocks are placed is sufficiently compacted. Mr Stanfield disagrees. He considers that they have been placed in uncontrolled fill.
  4. [88]
    The experts also disagree as to the proposed remedial method for dealing with the encroachment. Mr Stanfield thinks that if the proposed course, suggested by Mr Rienecker was adopted, that is to, effectively, concrete saw off the encroachment, the structural integrity of the wall would be further reduced. Mr Rienecker disagrees. Mr Stanfield also considers that the wall is continuing to deflect, while Mr Rienecker disagrees with this. Mr Stanfield said in relation to the drainage that during his observations of the original part of the wall he observed erosion of soils from behind the wall creating gapping between the bottom sleeper and the soil, an ineffective geotextile blanket as exposed drainage gravel and erosion from behind the wall, an unsocked ag-pipe, very moist and partly rotted sleepers, a break in the ag-pipe, the ag-pipe attempting to discharge uphill and his last reported sighting of it being at post eight.
  5. [89]
    I have already mentioned that I found Mr Rieneker’s evidence quite unhelpful.  I prefer Mr Stanfield’s evidence.  I was particularly unimpressed that Mr Rieneker had certified the wall on the basis of tie-back based on calculations using inputs including the depth of footing witch he had simply been told by Dr Alic rather than either he himself, or having one of his staff properly investigate the matter.  I also thought that certifying the wall as structurally sound where it had deflected after about 3 months was optimistic.  That proved to be correct given he specified further tie-backs in October 2021 immediately after Mr Stanfield’s report had expressed the opinion that there was more deflection.  This was 3 months after Mr Rieneker had last stated to the Council that the wall was structurally sound.


  1. [90]
    I have been provided with detailed written submissions by the parties which set out their position in terms of submissions and set out in detail reference to the authorities.  I have already made reference to the authorities relied upon, otherwise there is much in the submissions as to the differences in the evidence between the applicants and the respondents, and the differences in the expert evidence which I have already dealt with.
  2. [91]
    One of the submissions made for the respondent was that I would have regard to the suggestion that water emerging from the wall in fact emerges onto the respondents’ property.  That was said to be based on the proposition that the wall was 17 centimetres from the boundary.  The submissions for the applicants were that the wall was in fact between six and 17 centimetres from the boundary, and it is clear from some of the video evidence that water is both cascading onto the applicants’ land and flowing under the wall.  I accept the applicants’ submissions in that respect.
  3. [92]
    Next for the respondents, it was submitted that it was only Mr Anderson who suggested that the retaining wall was in any way impermeable, however, of course, he was only referring to the wooden parts of it which I would have thought were plainly impermeable.
  4. [93]
    Much was made in the submissions also about whether or not the requirements of the Core Consulting Report were required to be complied with as part of the development approval. As I have said, I am satisfied that there is non-compliance with the development approval in any case, and in terms of the injunction I am asked to order, I would not consider it to be relevant to that or what the precise terms of it might be to have regard to the contents of the Core Consulting Report.
  5. [94]
    So otherwise it was said for the respondents, in terms of discretionary matters relating to the application for injunction, or the injunctive relief sought rather, that the defects in the wall should be regarded as minor, and that the fall of the pipe may be remedied in some way short of demolition of the wall.  Having regard to what I have said as to Mr Stanfield’s evidence as to that matter which I accept, I do not accept that submission.
  6. [95]
    In my view, as a consequence of the 2015 works and the 2018 works and in particular the closeness of the sloping batter to the retaining wall, the removal in 2018 of the effluent bund and the ag-pipe not being laid properly in the sense that it does not have the appropriate fall and is not covered by a sock,  the applicants have been subjected to a more concentrated flow at the boundary than otherwise would be the case.
  7. [96]
    I am not satisfied that this concentrated flow results simply from the natural use of the respondents’ land. In particular, I do not consider that the undertaking of work such as the introduction of the close steep slope and the construction of the retaining wall without appropriate or approved drainage and in a way which is not structurally sound is a natural and reasonable use of the respondents’ land given the way it which it has contributed to an increase in the concentration of the flow of water.
  8. [97]
    As to the structural state of the wall, to the extent that those matters might be relevant to the granting or not of an injunction, I am conscious that it has footings of inappropriately shallow depth. I have also observed that it is built in a way where clearly the posts were not long enough, and from an aesthetic point of view, somebody has put another cut-off part of post material on the top whale to at least create the appearance that the posts do extend up past the top sleepers which does not inspire much confidence in the state of the wall more generally.  But because also of the serious difficulties with water crossing the boundary, both over, through and under the wall. It seems to me that the inferior footings are being undermined or exposed further.  . I accept the unchallenged evidence of Mr Stanfield that it would be more economical to demolish the wall and rebuild it than to try and fix the drainage. In any case, I am also satisfied on the basis of his evidence that the appropriate fall required for the ag-pipe cannot be introduced without demolishing the wall and cooperatively grading the boundary between the two properties to introduce the required fall. I also accept in this respect that seeking to do these works with the tiebacks in place is one of the reasons why it would be economically more sensible to proceed with the replacement of the wall.
  9. [98]
    Having regard to the faults with the wall and the batter behind it, as well as the continuing effect on the applicants’ land of the concentrated flows at the boundary, I consider it prima facie appropriate to grant an injunction for the removal and reconstruction of the wall. I am fortified in that view given the continuing deterioration in the condition of the wall exacerbated by the wholly defective drainage.
  10. [99]
    If it became a factor in respect of any further approval for a replacement wall, it would also provide the opportunity to comply with requirements of a report such as the Core Consulting Report, although as I have said, I do not make any finding that the respondents were obliged to comply with it.  I mean in terms of the order I make in that respect, I will hear the parties, obviously, as to the precise form of it but it seems to me that it should not be an engineer of the applicants’ choosing or anything of that kind. It should simply be an appropriately qualified engineer identified by the head of the relevant professional organisation.
  11. [100]
    I have expressed elsewhere that the 2019 works and the 2021 works are, in my view, consistent with the expert evidence, appropriate defensive steps that any land holder in the position of the applicants would take with respect to their property. They should have been taken back in 2013 instead of the then owner of the property installing the cut-off bund on the respondents’ land. The wall, once replaced, will not prevent all water travelling through it or perhaps over it onto the applicants’ land. Works of that kind simply constitute good building practice in relation to the development of the applicants’ land when the manner in which it is chosen to achieve a flat building platform is to cut below the natural height of the land using a cut batter slope instead of some other appropriately drained mechanism. In those circumstances I dismiss the applicants’ damages claim.


[1]  Construction was commenced on or about 29 June 2015 (defence, paragraph 3(a)).  The original part of the retaining wall and associated filling works were completed on 12 September 2015 (defence, paragraph 4(a)(i)) before the house which was completed on 10 August 2016 (defence, paragraph 3(a)) and the pool in 2017 (defence, paragraph 3(b)).  An extension to the retaining wall was constructed in February 2019.

[2]  Although it is uncontentious that some of the concrete footings encroach onto the applicants’ land.

[3]  See paragraph 2 of the applicants’ written opening.

[4]  Although this matter was the subject of re-examination of Mr Anderson.

[5]  Although the time is also identified as being earlier in 2018 in some documents although the evidence was that the relevant time was October 2018.   As to this see paragraph 13 of the statement of claim, but compare that with subparagraph 5(a) of the further and better particulars of the statement of claim and paragraph 5 of the applicants’ written opening.

[6]  See paragraph 3 of the applicants’ written opening.

[7]  See paragraph 17 of the applicants’ written opening.

[8]  This was a bund associated with the respondents’ effluent disposal area (which I refer to as the effluent bund) and is not to be confused with a trench and bund combination formerly on the respondents’ land adjacent the boundary with the applicants’ land and constructed by the applicants’ predecessor in title (“the cut-off bund”). 

[9]  See paragraph 23 of the applicants’ written opening.

[10]  Exhibit HS-3 to Dr Sunderland’s affidavit sworn 26 May 2021.

[11]  The 2013 EBIS report is exhibit 2.

[12]  That term is defined in paragraph 13 of the statement of claim.

[13]  It is pleaded that construction of the retaining wall was completed on or about 10 August 2016 and the extension in February 2019.

[14]  T1-25/18-35.

[15]  T 4-36/ 31-34.

[16]  (1962) 108 CLR 12.

[17]  At pages 48-49.

[18]  (1995) 86 LGERA 312.

[19]  At 316-317.

[20]  Bell v Pitt [1956] Tas SR 161, Burbury CJ; Gartner v Kidman (1962) 108 CLR 12 and Kraemers v Attorney-General (Tas) [1966] Tas SR 113.

[21]  At page 313.

[22]  At page 317.

[23]  (2013) 197 LGERA 381 at [135] per Emmett JA with whom Leeming JA and Sackville AJA, relevantly, agreed.

[24]  Gales Holdings Pty Ltd v Tweed Shire Council [2013] NSWCA 382, 544-545.

[25]  This was largely taken from the respondents’ opening but appears to be uncontroversial.

[26]  Affidavit of Dr Graham filed 3 March 2022 at paragraph 5.

[27]  See generally T2-25/35 – 27/34.

[28]  Affidavit of Dr Graham filed 3 March 2022 at paragraphs 9 and 10.

[29]  Affidavit of Dr Graham filed 3 March 2022 at paragraph 18.

[30]  Affidavit of Dr Graham filed 3 March 2022 at paragraph 12.

[31]  Affidavit of Dr Graham filed 16 June 2021 at paragraph 11.

[32]  Affidavit of Dr Graham filed 4 February 2022 at paragraph 10.

[33]         Affidavit of Dr Graham filed 16 June 2021 at paragraphs 20 and 21.

[34]  Affidavit of Dr Graham filed 16 June 2021 at paragraphs 23 and 24.

[35]  Affidavit of Dr Graham filed 16 June 2021 at paragraphs 25 and 26.

[36]  Affidavit of Dr Graham filed 16 June 2021 at paragraph 32.

[37]  Affidavit of Dr Graham filed 16 June 2021 at paragraph 34.

[38]  Affidavit of Dr Graham filed 16 June 2021 at paragraph 36.

[39]  Affidavit of Dr Sunderland filed 3 March 2022 at paragraph 6.

[40]  Affidavit of Dr Sunderland filed 3 March 2022 at paragraph 11.

[41]  Affidavit of Dr Sunderland filed 3 March 2022 at paragraph 12.

[42]  Affidavit of Dr Sunderland filed 3 March 2022 at paragraphs 17 and 18.

[43]  Affidavit of DR Sunderland filed 3 March 2022 at paragraph 19.

[44]  Affidavit of Dr Sunderland filed 3 March 2022 at paragraphs 25 and 26.

[45]  Affidavit of Dr Sunderland filed 3 March 2022 at paragraph 27.

[46]  Affidavit of Dr Sunderland filed 3 March 2022  at paragraph 28.

[47]  Affidavit of Dr Sunderland filed 3 March 2022 at paragraph 30.

[48]  Affidavit of Dr Sunderland filed 11 April 2022 at paragraph 3.

[49]  Affidavit of Dr Alic filed 25 January 2022 at paragraphs 8 and 10.

[50]  Affidavit of Dr Alic filed 25 January 2022 at paragraphs 9 and 11.

[51]  Affidavit of Dr Alic filed 25 January 2022 at paragraphs 31 and 40.

[52]  Affidavit of Dr Alic filed 25 January 2022 at paragraphs 51 and 58.

[53]  Affidavit of Dr Alic filed 25 January 2022 at paragraph 56.

[54]  Affidavit of Dr Alic dated 24 March 2022 at paragraph 19.

[55]  Affidavit of Dr Alic filed 25 January 2022 at paragraph 83.

[56]  Affidavit of Dr Alic filed 25 January 2022 at paragraph 23.

[57]  Affidavit of Dr Alic dated 24 March 2022 at paragraph 28.

[58]  Exhibit 2.

[60]  T 1-46 / 42-45.

[61]  T 4-27 / 4-15.

[62]  T 1-13 / 27-30.

[63]  T 1-13 / 31-35 and 45-47.

[64]  T 4-22 / 6-45.

[65]  T 4-64/ 1-5.

[66]  T 1-15 / 19-27.

[67]  T 1-26 / 30-37.

[68]  T 1-26 / 42-27 / 8.

[69]  T 1-32 / 12-17.

[70]  T 1-34 / 21-35 / 45.

[71]  T 1-36 / 45-37 / 29.

[72]  Being SKO1.

[73]  T 1-45 / 5-19

[74]  T 1-45 / 21-30 and T1-64 / 29-30 and 34-38

[75]  T 1-46 / 42-45

[76]   Tab 12 at page 124.

[77]  T 2-56 / 35-57 / 12.

[78]  T 2-62 / 26-29.

[79]  T 2-62 / 36-44.

[80]  T 2-64 / 5-16.

[81]  T 2-64 / 34-65 / 12.

[82] T 2-66 / 4-45.

[83]  T 2-69 / 24-70 / 16.


Editorial Notes

  • Published Case Name:

    Graham & Anor v Alic & Anor

  • Shortened Case Name:

    Graham v Alic

  • MNC:

    [2022] QDC 106

  • Court:


  • Judge(s):

    Jackson QC DCJ

  • Date:

    28 Apr 2022

Appeal Status

Please note, appeal data is presently unavailable for this judgment. This judgment may have been the subject of an appeal.

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