The applicant's and respondents' properties share a long common boundary. The trees are all on the respondents' property close to the boundary. In the back section of the respondents' property are:
an umbrella tree (Heptapleurum actinophyllum) (T1) estimated at 7 metres in height by Sam Allouche (arborist engaged by the applicant); and
a tall Cook pine (Araucaria columnaris) (T2), described as a 16-metre tall Norfolk Island pine (Araucaria heterophylla) by Mr Allouche.
Closer to the front of the respondents' property is a low hedge, or row, of lilly pilly trees (Syzygium sp.) (T3).
[2]
The applicant's property was the subject of a development from 2004, when two new dwelling were constructed on the property. Development works included excavation of the front part of the applicant's property, almost to the boundary, bringing the level down near street level, resulting in a significant level difference between the two properties along most of the common boundary.
The common boundary is almost 40 metres long. The applicant's wall is generally on the applicant's land close to the common boundary, as shown in the survey plan included in Exhibit C. For most of its length, it is a concrete block wall with an average height of approximately 3 metres. From its western end at the front of the property, most of the block wall is capped, the uncapped section beginning at approximately the point where the applicant's ground level returns to its original level, not far from T2. The remaining section of the wall near the eastern end of the boundary is brick.
The lower part of the block wall, and the ground exposed by excavation works below the wall, have been covered with shotcrete, which was sprayed on once excavation works were completed.
Michael Ell, an engineer engaged by the applicant, found the block wall lacked any reinforcing and its blocks were not filled with concrete. The parties generally agree on the nature of the block wall.
Sections of the block wall have rotated and lean into the applicant's property. The applicant alleges that this damage was caused by the respondents' trees, while the respondents assert that the damage was caused by factors other than their trees.
[3]
The applicant relies upon arboricultural evidence provided by Mr Allouche. Mr Allouche's investigations were limited to a visual inspection undertaken from within the applicant's land. Mr Allouche calculated T2's structural root zone radius as 2.85 metres. Referring to T2 as a Norfolk Island pine (I find it is more likely a Cook pine), Mr Allouche described roots of that species as "...known to be both vigorous, where they have increased strength capabilities, and invasive, where they grow and spread rapidly with undesirable outcomes". Mr Allouche wrote on p 11 of his report: "The Arborist [referring to himself] assumed that the trees are growing within two (2) metres of the common wall, and therefore it is highly probable that the wall is constructed within the SRZ [structural root zone] of both trees, where there would be a presence of large structural roots responsible for anchoring the trees in the soil, but also large enough to exert enough force to impact structures." From this rationale only, Mr Allouche concluded that "... the trees are a major contributing factor to the damage and displacement of common wall...".
Schedule 7 to the Uniform Civil Procedure Rules 2005 requires inter alia that an expert must state, for opinions expressed in a report: "(e) the reasons for and any literature or other materials utilised in support of each such opinion". The reasons given by Mr Allouche to support his conclusion that the trees are a major contributing factor to the condition of the wall are flimsy, at best. Mr Allouche undertook no investigations to support his contention that large structural roots were growing against and impacting the wall. Mr Leggat submitted that the Court's on-site inspection would confirm Mr Allouche's conclusion. In fact, the on-site inspection only cast Mr Allouche's conclusion into greater doubt. At the on-site inspection, the respondents pointed out the footing and remaining section of a wall on their property were close to the common boundary. The respondents' wall, partly breezeblock, partly other construction, has been removed above ground level. The remainder of the wall, including its footing, is separated from the applicant's wall by a gap some 40-50 mm wide. It separates the earth on the respondents' property from the applicant's wall. It appears undamaged. I observed the remaining sections of the respondents' wall in the vicinity of trees T1, T2 and T3. The respondents' photographs show the breezeblock wall before it was removed, undamaged and in apparently vertical alignment, while the applicant's wall was already rotated. This situation does not fit the scenario described by Mr Allouche.
While the respondents provided no expert arboricultural evidence to refute Mr Allouche's evidence, I find Mr Allouche's lack of investigation and reasoning in support of his conclusions leaves his evidence with little weight. My own observations of the situation led me to a different conclusion.
Michael Ell, an engineer engaged by the applicant, gave oral evidence during the on-site view and in Court. A report he had prepared earlier was not in evidence. Mr Ell described the wall and the significant extent of its rotation. Mr Ell suggested that trees T1, T2 and T3 move in the wind, resulting in their roots moving, which in turn causes rotational forces on the applicant's wall. He identified this as the primary cause of damage to the wall. Mr Ell undertook no investigations to confirm if roots of any of the trees did indeed grow against the applicant's wall. He seemed unaware of the presence of the respondents' wall between the trees and the applicant's wall.
Vadim Topolinsky, an engineer engaged by the applicant, provided written and oral evidence. Mr Topolinsky provided a report to the applicant in July 2019, and a further report in 2023 in response to the respondents' evidence. After inspecting the wall on 21 November 2018, Mr Topolinsky concluded (in the Executive Summary of the 2019 report) that the wall "... does not meet any of the design criteria required for a soil retaining structure...", and "... appears to have been chosen to bound the land and was not intended or appropriate to perform a function of a soil retaining structure...". He found that the wall "... has structurally failed and poses an immediate risk to property and occupant safety".
Mr Topolinsky's instructions, according to his 'Brief', were to review documents provided to him and to offer an opinion as to whether the "... wall in question falls within the definition of the Dividing Fences Act 1991" and whether the trees have contributed to the wall's damage. He was asked to consider certain factors as being relevant to his review, including that the excavation works on the applicant's property "... did not in any way contribute to the imminent collapse of the wall" and that "... the 'sprayed concrete' which was applied by Zante to the base of the wall at the time of construction served to provide the wall with much need stability". On my reading of his Brief, Mr Topolinsky was asked to assume these statements as facts. He was also asked to consider that the wall's footings "... do not appear to have a toe".
Mr Topolinsky found that "... there appears to be a close correlation between some of cracking locations [sic] (and associated lateral wall displacement) and larger trees located directly behind..." the wall. The Court's on-site observations contradict this:
the wall is not significantly displaced near the largest tree, T2;
the areas of greatest rotation are not in line with any of trees T1, T2 or T3; and
the area of rotation along the wall corresponds more closely with the area excavated on the applicant's land than it does with the respondents' trees.
Mr Topolinsky then stated: "I do not have sufficient information to determine the effects of existing trees or their root systems upon the Boundary Wall". Despite this, he said that "... I believe that the trees... have contributed to the current condition of the Boundary Wall". I agree with his statement regarding a lack of information. Mr Topolinsky undertook no investigation to determine if any tree roots grew to the wall or pushed against it. In oral evidence, he stated that he was unaware of the presence of the respondents' wall behind the applicant's wall. Mr Topolinsky might believe that the trees have contributed to the damage, but has provided no evidence to support his belief.
During the on-site view, while on the front part of the respondents' property near the lilly pilly hedge (T3), the Court observed that the applicant's wall's footing was visible behind the respondents' wall. The applicant's footing was vertical and not tilted; only the wall above it was tilted. There was no lateral load from the respondents' property on that part of the wall. Mr Topolinsky suggested the wall here had rotated due to the adjacent section's rotation, caused by trees. However, the tilted section of wall was not attached to the adjacent part of the wall to the east, but was separated by a construction joint or gap. It had moved independently of the adjacent section. Its movement was clearly not caused by trees.
Anthony Grieve, a building consultant and engineer engaged by the respondents, inspected the site on 8 June 2023 and reviewed documents provided to him. Relying on documents and photographs, Mr Grieve found that the applicant's wall was in a serviceable condition in 2003, prior to development of the applicant's land. He estimated that in 2003 the wall had rotated some 30 mm at its top, whereas in 2023 it was in danger of collapse.
Mr Grieve identified that the applicant's development included no changes to the wall, but stated that it was essential that a retaining wall be specified for the boundary because of the difference between ground level on the applicant's and respondents' respective properties. Mr Grieve suggested the applicant had not complied with development requirements, in particular a clause requiring structural details of retaining walls. Mr Grieve found the difference in ground levels between the properties, and the need for a specified retaining wall, resulted from the excavation works within the applicant's property.
Of interest here, I note that the applicant submits that lateral loading on its wall is a result of the respondents building up the ground level on their side of the wall. The engineers engaged by the applicant repeat this proposition. However, the respondents submitted that they have not raised soil levels against the wall on their property. The Court's on-site observations support the respondents' submission: their soil level has not been raised such that it provides any loading against the applicant's wall. The top of the remainder of the respondent's wall is visible for most of the length of the boundary, or can be seen by scraping away a small amount of soil.
Returning to Mr Grieve's report, he expressed an opinion that the pine (T2) would have an effect of applying pressure to the applicant's wall. He undertook no investigation to support this opinion.
The engineers and the arborist have all expressed opinions on causation of the damage. What is striking in this matter is that none of them undertook any site investigations to support their conclusions, which are based on possibilities and theories. Neither of the engineers engaged by the applicant even seemed aware of the wall on the respondents' property between the trees and the applicant's wall, yet were able to attribute the wall's rotation to either soil loads against the wall on the respondents' side or movement of roots against the wall. On-site observations make either scenario so unlikely that the Court cannot be satisfied, to the extent required at s 10(1)(a) of the Trees Act, that the trees have caused any damage. The applicant's evidence does not demonstrate any causal nexus between the trees and the damage: see Smith & Hannaford v Zhang & Zhou[2011] NSWLEC 29, at [38]. The Court listed investigations that might be undertaken to demonstrate such a nexus, should one exist, in the principle at [59] in Fang v Li & anor[2017] NSWLEC 1503. No such investigations have been undertaken.
Mr Leggat suggested that the onus is on the respondents to demonstrate that excavation caused the damage. That might be so if the applicant had demonstrated to the Court's satisfaction that trees caused the damage while the respondents disputed this. However, the primary burden of proof lies with the applicant. On the evidence before the Court, I cannot be satisfied that the respondents' trees caused damage, so the respondents have no obligation to demonstrate otherwise.
Not only is there a lack of evidence to support the applicant's claim that trees have damaged the wall, the Court's on-site observations suggest otherwise:
damage to the applicant's wall corresponds more closely with the area of excavation works on the applicant's property than it does with trees on the respondents' property;
some of the most significant areas of rotation of the wall are demonstrably unrelated to trees;
the respondents' wall appears to provide a barrier between the trees and the applicant's wall;
where some sections of the applicant's wall have rotated above ground level, its footing has not been displaced, so the wall's rotation has not resulted from loads on the respondents' side; and
the applicant's wall was clearly not designed or constructed for the current site conditions.
The Court cannot be satisfied that the respondents' trees have caused, are causing, or are likely in the near future to cause damage to the applicant's property. Notwithstanding this finding, even if the trees have contributed in some as-yet undemonstrated way to the applicant's wall's damage, the major contributing factor appears to be the inadequacy of the wall's structure of the current site conditions. Any contribution by the trees to damage would be so relatively minor as to not warrant apportioning to the respondents any costs of remedy.
[4]
Mr Leggat submitted that the trees have caused the damage resulting in the risk of imminent wall failure, which would, if it occurred, cause injury to people on the applicant's property. I have found that the trees have not caused damage. Furthermore, injury resulting from failure of the wall would be injury caused by the wall, not by the trees: see Golden v French[2022] NSWLEC 1642 at [32]-[34].
The application included orders to replace the entirety of the applicant's wall. The applicant submitted that those orders were being sought under s 13A of the Dividing Fences Act 1991 for parts of the wall that were not damaged by the trees. Dr Smith objected to this on the grounds that the respondent has sought fencing orders through separate proceedings and there has been no application to transfer those proceedings to this Court. Because I am not satisfied that the trees have caused damage to the wall, no orders can be made for the wall in these proceedings. Therefore, there is no need for me to make any determination on this element of the application.
[7]
Dr Smith submitted that the applicant first became aware of damage to the wall in 2003. The applicant obtained a report from Mr Ell in December 2016 which found the wall may be close to collapse. Dr Smith submitted that the applicant is barred by s 14(1)(d) of the Limitation Act 1969 from bringing these proceedings more than six years after becoming aware of the problem. Because I am not satisfied that the trees have caused damage to the wall, there is no need for me to make any determination on this issue.
[8]
(1) The application is refused.
(2) The exhibits are returned, other than Exhibit A.
Parties
Applicant/Plaintiff:
Zante Investments Pty Ltd
Respondent/Defendant:
Jarvis
Legislation Cited (3)
Fences Act 1991
(Disputes Between Neighbours) Act 2006
Civil Procedure Rules 2005
Cases Cited (4)
Notice of the application
Dr Smith submitted that the applicant did not give the respondents at least 21 days notice of the application as required by s 8(1) of the Trees Act.
In Ball v Bahramali & Anor [2010] NSWLEC 1334, Fakes C wrote at [38]:
"38 With respect to Mr Gerathy's contentions concerning the notice given by the applicant and compliance with s 14C(1) the application was filed with the Court on 19 August. The date specified and stamped in the application by the Court regarding when the application had to be served on the respondents and other parties was 27 August. The matter was listed for a preliminary hearing on 21 September 2010. This information is recorded in the application; this was copied and made available to the applicant. Thus there was at least 21 days notice specified by the Court for the serving of documents and the preliminary hearing and therefore compliance with s 14C(1)."
Practice Note 12 of the Court's Practice Note Class 2 Tree Applications:
"12. Tree applications will be given a date, time and place for a preliminary hearing which corresponds with the next available preliminary hearing after the expiry of the statutory period of 21 days for service of the tree application. This will usually be 4 to 6 weeks after filing of the tree application. The preliminary hearing will usually be before a Registrar of the Court."
I find that the timeline set out by the Court allowed for the required 21 days notice in these proceedings. The respondents were provided with a reasonable timeframe to obtain and file evidence and this timeframe was then extended to allow the respondents further time.
Cause of damage
The applicant relies upon arboricultural evidence provided by Mr Allouche. Mr Allouche's investigations were limited to a visual inspection undertaken from within the applicant's land. Mr Allouche calculated T2's structural root zone radius as 2.85 metres. Referring to T2 as a Norfolk Island pine (I find it is more likely a Cook pine), Mr Allouche described roots of that species as "…known to be both vigorous, where they have increased strength capabilities, and invasive, where they grow and spread rapidly with undesirable outcomes". Mr Allouche wrote on p 11 of his report: "The Arborist [referring to himself] assumed that the trees are growing within two (2) metres of the common wall, and therefore it is highly probable that the wall is constructed within the SRZ [structural root zone] of both trees, where there would be a presence of large structural roots responsible for anchoring the trees in the soil, but also large enough to exert enough force to impact structures." From this rationale only, Mr Allouche concluded that "… the trees are a major contributing factor to the damage and displacement of common wall…".
Schedule 7 to the Uniform Civil Procedure Rules 2005 requires inter alia that an expert must state, for opinions expressed in a report: "(e) the reasons for and any literature or other materials utilised in support of each such opinion". The reasons given by Mr Allouche to support his conclusion that the trees are a major contributing factor to the condition of the wall are flimsy, at best. Mr Allouche undertook no investigations to support his contention that large structural roots were growing against and impacting the wall. Mr Leggat submitted that the Court's on-site inspection would confirm Mr Allouche's conclusion. In fact, the on-site inspection only cast Mr Allouche's conclusion into greater doubt. At the on-site inspection, the respondents pointed out the footing and remaining section of a wall on their property were close to the common boundary. The respondents' wall, partly breezeblock, partly other construction, has been removed above ground level. The remainder of the wall, including its footing, is separated from the applicant's wall by a gap some 40-50 mm wide. It separates the earth on the respondents' property from the applicant's wall. It appears undamaged. I observed the remaining sections of the respondents' wall in the vicinity of trees T1, T2 and T3. The respondents' photographs show the breezeblock wall before it was removed, undamaged and in apparently vertical alignment, while the applicant's wall was already rotated. This situation does not fit the scenario described by Mr Allouche.
While the respondents provided no expert arboricultural evidence to refute Mr Allouche's evidence, I find Mr Allouche's lack of investigation and reasoning in support of his conclusions leaves his evidence with little weight. My own observations of the situation led me to a different conclusion.
Whether the trees are likely to cause injury
Mr Leggat submitted that the trees have caused the damage resulting in the risk of imminent wall failure, which would, if it occurred, cause injury to people on the applicant's property. I have found that the trees have not caused damage. Furthermore, injury resulting from failure of the wall would be injury caused by the wall, not by the trees: see Golden v French [2022] NSWLEC 1642 at [32]-[34].
Michael Ell, an engineer engaged by the applicant, gave oral evidence during the on-site view and in Court. A report he had prepared earlier was not in evidence. Mr Ell described the wall and the significant extent of its rotation. Mr Ell suggested that trees T1, T2 and T3 move in the wind, resulting in their roots moving, which in turn causes rotational forces on the applicant's wall. He identified this as the primary cause of damage to the wall. Mr Ell undertook no investigations to confirm if roots of any of the trees did indeed grow against the applicant's wall. He seemed unaware of the presence of the respondents' wall between the trees and the applicant's wall.
Vadim Topolinsky, an engineer engaged by the applicant, provided written and oral evidence. Mr Topolinsky provided a report to the applicant in July 2019, and a further report in 2023 in response to the respondents' evidence. After inspecting the wall on 21 November 2018, Mr Topolinsky concluded (in the Executive Summary of the 2019 report) that the wall "… does not meet any of the design criteria required for a soil retaining structure…", and "… appears to have been chosen to bound the land and was not intended or appropriate to perform a function of a soil retaining structure…". He found that the wall "… has structurally failed and poses an immediate risk to property and occupant safety".
Mr Topolinsky's instructions, according to his 'Brief', were to review documents provided to him and to offer an opinion as to whether the "… wall in question falls within the definition of the Dividing Fences Act 1991" and whether the trees have contributed to the wall's damage. He was asked to consider certain factors as being relevant to his review, including that the excavation works on the applicant's property "… did not in any way contribute to the imminent collapse of the wall" and that "… the 'sprayed concrete' which was applied by Zante to the base of the wall at the time of construction served to provide the wall with much need stability". On my reading of his Brief, Mr Topolinsky was asked to assume these statements as facts. He was also asked to consider that the wall's footings "… do not appear to have a toe".
Mr Topolinsky found that "… there appears to be a close correlation between some of cracking locations [sic] (and associated lateral wall displacement) and larger trees located directly behind…" the wall. The Court's on-site observations contradict this:
the wall is not significantly displaced near the largest tree, T2;
the areas of greatest rotation are not in line with any of trees T1, T2 or T3; and
the area of rotation along the wall corresponds more closely with the area excavated on the applicant's land than it does with the respondents' trees.
Mr Topolinsky then stated: "I do not have sufficient information to determine the effects of existing trees or their root systems upon the Boundary Wall". Despite this, he said that "… I believe that the trees… have contributed to the current condition of the Boundary Wall". I agree with his statement regarding a lack of information. Mr Topolinsky undertook no investigation to determine if any tree roots grew to the wall or pushed against it. In oral evidence, he stated that he was unaware of the presence of the respondents' wall behind the applicant's wall. Mr Topolinsky might believe that the trees have contributed to the damage, but has provided no evidence to support his belief.
During the on-site view, while on the front part of the respondents' property near the lilly pilly hedge (T3), the Court observed that the applicant's wall's footing was visible behind the respondents' wall. The applicant's footing was vertical and not tilted; only the wall above it was tilted. There was no lateral load from the respondents' property on that part of the wall. Mr Topolinsky suggested the wall here had rotated due to the adjacent section's rotation, caused by trees. However, the tilted section of wall was not attached to the adjacent part of the wall to the east, but was separated by a construction joint or gap. It had moved independently of the adjacent section. Its movement was clearly not caused by trees.
Anthony Grieve, a building consultant and engineer engaged by the respondents, inspected the site on 8 June 2023 and reviewed documents provided to him. Relying on documents and photographs, Mr Grieve found that the applicant's wall was in a serviceable condition in 2003, prior to development of the applicant's land. He estimated that in 2003 the wall had rotated some 30 mm at its top, whereas in 2023 it was in danger of collapse.
Mr Grieve identified that the applicant's development included no changes to the wall, but stated that it was essential that a retaining wall be specified for the boundary because of the difference between ground level on the applicant's and respondents' respective properties. Mr Grieve suggested the applicant had not complied with development requirements, in particular a clause requiring structural details of retaining walls. Mr Grieve found the difference in ground levels between the properties, and the need for a specified retaining wall, resulted from the excavation works within the applicant's property.
Of interest here, I note that the applicant submits that lateral loading on its wall is a result of the respondents building up the ground level on their side of the wall. The engineers engaged by the applicant repeat this proposition. However, the respondents submitted that they have not raised soil levels against the wall on their property. The Court's on-site observations support the respondents' submission: their soil level has not been raised such that it provides any loading against the applicant's wall. The top of the remainder of the respondent's wall is visible for most of the length of the boundary, or can be seen by scraping away a small amount of soil.
Returning to Mr Grieve's report, he expressed an opinion that the pine (T2) would have an effect of applying pressure to the applicant's wall. He undertook no investigation to support this opinion.
The engineers and the arborist have all expressed opinions on causation of the damage. What is striking in this matter is that none of them undertook any site investigations to support their conclusions, which are based on possibilities and theories. Neither of the engineers engaged by the applicant even seemed aware of the wall on the respondents' property between the trees and the applicant's wall, yet were able to attribute the wall's rotation to either soil loads against the wall on the respondents' side or movement of roots against the wall. On-site observations make either scenario so unlikely that the Court cannot be satisfied, to the extent required at s 10(1)(a) of the Trees Act, that the trees have caused any damage. The applicant's evidence does not demonstrate any causal nexus between the trees and the damage: see Smith & Hannaford v Zhang & Zhou [2011] NSWLEC 29, at [38]. The Court listed investigations that might be undertaken to demonstrate such a nexus, should one exist, in the principle at [59] in Fang v Li & anor [2017] NSWLEC 1503. No such investigations have been undertaken.
Mr Leggat suggested that the onus is on the respondents to demonstrate that excavation caused the damage. That might be so if the applicant had demonstrated to the Court's satisfaction that trees caused the damage while the respondents disputed this. However, the primary burden of proof lies with the applicant. On the evidence before the Court, I cannot be satisfied that the respondents' trees caused damage, so the respondents have no obligation to demonstrate otherwise.
Not only is there a lack of evidence to support the applicant's claim that trees have damaged the wall, the Court's on-site observations suggest otherwise:
damage to the applicant's wall corresponds more closely with the area of excavation works on the applicant's property than it does with trees on the respondents' property;
some of the most significant areas of rotation of the wall are demonstrably unrelated to trees;
the respondents' wall appears to provide a barrier between the trees and the applicant's wall;
where some sections of the applicant's wall have rotated above ground level, its footing has not been displaced, so the wall's rotation has not resulted from loads on the respondents' side; and
the applicant's wall was clearly not designed or constructed for the current site conditions.
The Court cannot be satisfied that the respondents' trees have caused, are causing, or are likely in the near future to cause damage to the applicant's property. Notwithstanding this finding, even if the trees have contributed in some as-yet undemonstrated way to the applicant's wall's damage, the major contributing factor appears to be the inadequacy of the wall's structure of the current site conditions. Any contribution by the trees to damage would be so relatively minor as to not warrant apportioning to the respondents any costs of remedy.