JUDGMENT
Outline
1 The plaintiff strata corporation claims that the roots of a camphor laurel tree in Edgecliff Road have caused a retaining wall on the boundary of its property and the road to fail and be in danger of imminent collapse. It seeks an order restraining the Council from continuing the nuisance or a mandatory order for removal of the tree, plus damages.
Facts
2 The owners - Strata Plan No. 13218 being a body corporate under the Strata Titles (Freehold Development) Act 1973 is the owner of the common property land in Strata Plan 13218. The property known as "Edgemount", number 291 Edgecliff Road, Woollahra, is erected on the land on the strata plan. I will call the plaintiff "the owners". Edgecliff Road is a public road within the municipal area of Woollahra Municipal Council (the Council). Pursuant to s145 of the Roads Act 1993 the road is vested in the Council in fee simple. The Council is responsible for the care, control and management of the road but is not the occupier: Roads Act s146(1)(a)(d).
3 A large camphor laurel tree grows on the eastern road verge adjacent to the property of the owners. There is a significant drop from the road to the owners' land, the road or footpath being retained by a stone wall built almost entirely on the owners' land.
4 Mr Hackett has lived in Unit 4 in "Edgemount" since 1978. The tree was a big tree when he purchased his unit. Cracks in the footpath and lifting of the footpath in the area near the tree have been obvious over the years. In the mid 1980s the Council repaved the footpath where it had been lifting. Mr Hackett had noticed some cracking in the wall quite early during his occupation. He said the position of the wall got worse during the 1990s. The top of the wall was bowing eastwards. The owners were told in 1997 that the wall had failed and should be propped up and props were put against it and still remain in position. In 1997 the owners and Council agreed that Coffey Partners International Pty Ltd, Geotechnical Engineers, would be retained to investigate the cause of the wall buckling and its failure and to report on it. A trench was excavated on the footpath area near the tree and was enlarged and deepened by Mr Lumsdaine, an associate of Coffey Partners. The investigation disclosed quite large roots from the tree running parallel to the boundary beneath the footpath area and towards a service pit wall, apparently placed in position about twenty years ago. The report from Coffey Partners expressed the clear opinion that the damage to the wall was caused as a result of pressure caused by the roots of the tree. Photographs in evidence clearly show a root system and some roots of considerable size.
5 Apparently the Council was not convinced by the report and arranged for a further report to be obtained from GHD-Longmac Pty Ltd. Mr Davies, the principal geotechnical engineer of that company conducted a further investigation; additional test pits were dug in the trench area for the purposes of this. He considered that the "wall distress" namely the tilting and bowing resulted from inadequate design and construction of the wall and that the tree root system had not been influential in this.
6 After all the inspections had taken place Council filled the trench. This was done with a cement and sand mixture in layers and the evidence establishes that by using this method Council ensured that little if any pressure would be exerted on the wall as a result of filling the trench. Thereafter the footpath area was also re-concreted. Since that date cracks have appeared at the edge of the re-concreted area of the footpath, and it is obvious that pressures are being exerted upon it.
Pleadings
7 The owners' main claim is in nuisance. It is claimed first that the failure of the wall has been caused upon it by pressure from Edgecliff Road, the road verge and the footpath which are supported by it. No evidence adduced went to this. The real claim is that the roots of the camphor laurel tree have caused pressures on the wall which have caused it to fail. It is said that the Council caused or adopted and continued this nuisance. There was a third claim made in negligence which was less strongly argued. In essence the negligence claim was that since 1997 the Council had been aware of the failure of the wall and its dangerous condition, that it owed a duty of care to the owners to safeguard them against loss, damage or injury and that it had breached this duty of care. It is claimed that reconstruction of the wall to render it safe requires work to be carried out on Council land or at least under Council control and also requires approval of the Council as owner of the land. That is admitted and it is clear that work on the retaining wall would require some work on the adjacent footpath area. It is also claimed and admitted that removal of the camphor laurel tree would require the consent of the Council as owner of the road land and as the consent authority under the Woollahra Municipality Tree Preservation Order. The relief claimed by the owners is first an order that the Council demolish the retaining wall and reconstruct it to provide proper support for its land, being the road; secondly, that such relief as is necessary to abate the nuisance be given; and thirdly, damages. I should add here that although there was evidence adduced by the plaintiff as to the work required to reconstruct the wall, there was no evidence as to the cost, the owners, for some reason appearing to think that an order could or would be made that the defendant rebuild the wall. Thus there was no evidence to support the claim for damages, albeit that damage was a necessary component of the claim in negligence if it were to succeed and, of course, for the nuisance claim insofar as it was not limited to injunctive relief. Fortunately for the plaintiff, no point was made about this and it was agreed that if it were appropriate to award damages then the quantum of those damages should be determined in a separate hearing, presumably before me or before a Master.
8 By its defence, the Council denies that any damage to the wall has been caused by its activities or by the camphor laurel tree. Its main defence, however, is based on the highway immunity rule and the law relating to non-feasance by public authorities. The Council denies that it planted the tree or that it had anything to do with its planting and therefore denies that it had any duty to prevent the tree roots causing damage, or to repair, so as to give rise to a claim in nuisance or in negligence.
Decision on cause of failure of wall
9 To a large extent this depends upon whether the opinion of Coffey Partners or that of GHD-Longmac is accepted. I have no hesitation in preferring the evidence of Mr Lumsdaine over that of Mr Davies. I should say that the evidence of Mr Lumsdaine was supported by evidence given by Mr Crane, albeit that the main purpose of his report was to prepare a design for the retaining wall. Nevertheless he came to the conclusion that the damage to the existing wall was caused by roots from the camphor laurel tree. In addition Dr. Redman who had inspected the site quite recently, and who had seen the photographs, but who had not been present when the trench was opened up, supported the Coffey findings. It is perfectly clear from the photographs tendered in evidence that tree roots of the camphor laurel of substantial size are present and run below the pavement parallel to the road, adjacent to the wall. I accept the evidence of Mr Lumsdaine that there was present in the trench, some sandstone particle type material and that the pressure of the tree roots as the roots grew would cause compaction of these pieces of hard material against each other, which would exert pressure on the wall. I also accept his evidence that the existence of the edge of the services pit would cause additional pressure to be exerted on the wall by the roots. The fact that the wall has failed between the camphor laurel tree and the pit, but has not failed further away gave further support to opinion of Mr Lumsdaine. The plans of Mr Davies, tended to give a false impression of the position of the main crack or failure in the wall, although I do not think intentionally. In cross-examination, he agreed the point of failure was as shown on the plan of Mr Lumsdaine in a place consistent with the location of what appears to be the largest root. The reasons given by Mr Davies for the collapse of the wall, namely inadequate design and construction, did not explain why the wall was standing without problem further along the roadway, neither was their any evidence of actual events or happenings to support his theory that pressures which might have been exerted by heavy vehicles on the pavement during construction of the service pit. There was no evidence that those vehicles had been present. The fact that even since the trench has been re-filled, cracking has recommenced at the edge of the reconstructed footpath, points to continuing problems with the tree from its roots and the likelihood that unless something is done, there would be continuing problems even if the wall is rebuilt, although perhaps not for some time. The fact that the wall is inadequately constructed in that its design and construction does not accord with modern engineering requirements is not really relevant. What is relevant is whether or not the tree and its roots have caused a nuisance which has caused the wall to fail. I find that to be the position.
Public highway immunity rule
10 In Buckle v Bayswater Road Board (1936) 57 CLR 259 at 281, Dixon J said:
It is well settled that no civil liability is incurred by a road authority by reason of any neglect on its part to construct, repair or maintain a road or other highway. Such a liability may, of course, be imposed by statute. But to do so a legislative intention must appear to impose an absolute, as distinguished from a discretionary, duty of repair and to confer a correlative private right (Cf. City of Vancouver v. McPhalen (1911) 45 S.C.R. (Can.) 194).
No civil liability arises from the incorporated character of the road authority, or from the fact that it is expressly made liable to be sued (Gibson v. Mayor of Preston 57 (1870) L.R. 5 Q.B. 218). Nor is its responsibility affected by statutory provisions vesting the soil of the highway in it, or placing the highway under its management and control (Cowley v. Newmarket Local Board (1892) A.C. 345; Municipal Council of Sydney v. Bourke (1895) A.C. 433).