The trees
35With regards to Trees 1 and 2, in many matters heard under the Trees Act, an assumption is made that due to the proximity of a tree to a structure (that may or may not be damaged), the tree is likely to have caused, or could in the future cause, damage to that structure. In Smith & Hannaford v Zhang & Zhou [2011] NSWLEC 29 Craig J discussed the obligation created by s 10 for the Court to be satisfied of the causal nexus between the tree the subject of an application and the damage claimed by the applicants. This requires an assessment of all the evidence before the Court. This evidence may be factors other than the tree and which may require the input of a range of expert witnesses. At [62] Craig J stated
As the respondents submitted, something more than a theoretical possibility is required in order to engage the power under [the Trees Act] to make an order to remedy, restrain or prevent damage as a consequence of a tree. In the language of Jenkinson J in MacDonald , confidence on a "bare preponderance of probability" has not been engendered on the evidence adduced that the Sydney Blue Gum was a cause of damage to the applicants' dwelling. Embracing the language of the applicants' submission, I have not been left in a state of belief, on the balance of probabilities, that the tree is a cause of that damage."
36As Craig J was not satisfied on the evidence in Smith & Hannaford , I am not satisfied on the evidence before me that the damage to the retaining wall near Tree 1 has been caused by Tree 1. There is no obvious damage to the wall in the vicinity of Tree 2. Therefore I am not satisfied that either of these trees has caused, or is causing, damage to the retaining wall. Section 10(2) also refers to 'future damage'. The guidance decision in Yang v Scerri [2007] NSWLEC 592 considers the 'near future' to be a period of 12 months from the hearing. In the circumstances of this matter I consider that time frame to be appropriate. On this basis, I do not consider either tree is likely to cause damage to the wall in the near future.
37Therefore as a consequence, as the tests in s 10(2) are not met for Trees 1 and 2, the Court has no jurisdiction to make any orders for the removal of these trees or compensation for damage to the parts of the wall in proximity to them.
38With respect to Trees 3 and 4, I am satisfied, on the balance of probability, given the fact that these trees are pressing against the wall, they have contributed to the damage to approximately 1.5m sections of retaining wall immediately adjacent to the base of each of the trees.
39Therefore as s 10(2) is satisfied, the Court may make orders in respect of these trees. However, s 12(h)(i) is a necessary consideration. In this matter, the retaining wall is at least 31 years old, if not 43 years old. The uncontested evidence is that the wall has not been constructed to modern standards, is not on appropriate footings, and has no weep holes or steel reinforcing. The applicant rejects the impact of soil and water pressure. The applicant also discounted the veracity of the respondent's expert's report as the report said the wall was only 'at least 10 years old' when he (the applicant) knew it to be much older. I consider this assertion to be unfounded as the report clearly states that the author was 'not informed of its exact age'.
40I consider that while the physical pressure of the roots of Trees 3 and 4 has contributed to the displacement of the wall in their immediate vicinity, it is the age and construction of the wall, in combination with the pressure of soil and water that are likely to have migrated down slope over the decades the wall has been in existence, that are the major factors contributing to its condition. I also find it difficult to accept the applicant's contention that the trees have pushed the entirety of the wall onto his property. It is difficult to understand how this could occur in such an even fashion along its length. A more likely explanation is that the wall was constructed on his property in the first place.
41However, because of the contribution of the respondent's trees to damage to part of the retaining wall, some contribution to its repair or replacement will be ordered. Orders will also be made for the removal of Trees 3 and 4 due to the ongoing impact the trees will have on the wall or its replacement. The removal of these trees will be at the respondent's expense.
42Considering Trees 5 and 6 and the retaining wall, there is slight cracking of the mortar in the vicinity of Tree 5 and dislodgement of three of the top blocks near Tree 6. I am not satisfied that the nexus between the trees and the defects has been proven on the balance of probabilities. The mortar between the blocks is old and is similarly cracked in other sections of the wall away from trees. The build up of soil and other low growing vegetation may have placed some pressure on the week mortar. Even if I were to find some contribution from the trees, as a matter of discretion, I am not minded to make any orders with respect to the wall, however, I am satisfied that Trees 5 and 6 will need to be removed to enable the reconstruction of the dividing fence. The cost of removal is to be at the respondent's expense.