Claim against highway authority for damage caused to house by encroachment of tree roots — Only issue on appeal was whether encroachment gave rise to a reasonably foreseeable risk of subsidence — Trial judge decided in favour of plaintiff and highway authority appealed — Vital question was whether the authority should reasonably have foreseen that there might be pockets of clay under the house so that the foundations rested partly on plateau gravel and partly on clay, with consequent risk of subsidence — After a detailed consideration of the evidence before the judge the Court of Appeal did not accept that the risk was reasonably foreseeable — The possibility of an intrusion of clay under the respondent’s house was no more than a vague possibility, not a real risk — Even assuming that there was a real risk, it was an outside chance and had as such to be balanced against the practical steps which could reasonably have been taken by the appellants to minimise the damage — There was no breach of duty and consequently no nuisance — Authority’s appeal allowed
This was an
appeal by Hampshire County Council from a judgment of Stocker J in favour of
Brian Thomas Solloway, the freehold owner of a house at 72 Shirley Avenue,
Shirley, Southampton, which had suffered structural damage. Mr Solloway, the
plaintiff in the action, complained, and the judge found that subsidence at the
house, caused by the encroachment of the roots of a horse chestnut tree on the
adjacent highway, was a nuisance for which the defendants, the present
appellants, were responsible.
John J Smyth
QC and Richard Dening (instructed by Hepherd, Winstanley & Pugh, of
Southampton) appeared on behalf of the respondent, the plaintiff in the action;
John Foy (instructed by Theodore Goddard & Co, agents for R A Leyland,
solicitor and county secretary, Winchester) represented the appellants,
defendants in the action.
Giving the
first judgment at the invitation of Stephenson LJ, DUNN LJ said: This is an
appeal from a judgment of Stocker J given on February 20 1980. The learned
judge held that the subsidence at the plaintiff’s house, caused by the
encroachment of roots of a horse chestnut tree on the highway adjacent to the
house constituted a nuisance for which the defendants, as the highway
authority, were responsible.
There were
numerous issues at the trial. There was an issue of causation, there was an
issue of contributory negligence, there was an issue of law and there was an
issue as to the responsibility of a highway authority for a nuisance of this
kind; but the only issue on the appeal has been whether the encroachment by the
roots gave rise to a reasonably foreseeable risk of subsidence. The judge held
that it did; the defendant appellants contend that it did not.
The case has
been well argued and I personally am indebted to all counsel, both for their
arguments in this court and in the way in which the evidence was presented in
the court below.
The primary
facts as found by the judge were accepted by Mr Foy, for the appellants. Those
facts are fully set out in the judgment and it is not necessary for me to do
more than to summarise them. The plaintiff is the freehold owner of the house,
which he bought in 1967. Outside the house there is a horse chestnut tree, probably
planted in about 1874 and long before Shirley Avenue became a residential
street. No 72, which is the plaintiff’s house, was built in about 1922. The
foundations of it lie at a depth of about 2 ft below the surface of the ground.
Such foundations conformed to local building requirements at the time when the
house was built, but would not be considered adequate for a house of this size
if built today. There was no evidence of any significant structural damage to
the house over the 50 years or more of its existence, until the events giving
rise to this claim.
Immediately
outside the boundary of the plaintiff’s house stands the horse chestnut tree.
It is about 60 ft high and stands in the pavement a few feet from the front
fence of the property: to be exact, at 8.3 metres from the nearest point of the
house, which is the window at the bay of the house. Over the years there was
some trouble with the drainage, owing to blockage of the drains by roots from
the horse chestnut tree. This occurred in 1968, 1970 and 1971. On the first
occasion the plaintiff wrote to the local council asking them to top the tree
and see to its roots, but he received no reply. It is accepted that the
blockage of the drains by the roots has no relevance to the question of foreseeability
of the subsidence.
The position,
therefore, as found by the judge was that the plaintiff lived in the house from
1967 to 1976 unaware of any threat to the structure from the chestnut tree on
the roadway outside.
In August 1976
the plaintiff and his wife went on holiday for some three weeks. Some time
before doing so, substantial redecoration and repair work had been done to the
house, including rebuilding of the chimney stacks and work to the bay windows.
No structural damage was observed at the time of those works.
In 1976
occurred the second successive very hot summer, with drought conditions, which
had lasted since the summer of 1975. On return from his holiday the plaintiff
observed substantial cracks in the fabric of the house. These cracks were in
the area of the bay window and the side walls of the building. Rectification of
the building was carried out by means of underpinning. The agreed cost of this
work was £5,656.04, and that was the amount of the damage which the judge
ordered for the nuisance.
The judge made
crucial findings as to the subsoil under this house and they are so important
that I read that passage of his judgment in full. He said:
Shirley
Avenue is situated in an area, the top sub-soil of which is plateau gravel. In
so far as small pockets of clay outcrop may exist, they are of insufficient
size to appear at all on the geological plan. A house founded on plateau gravel
is unlikely to be affected by intrusion from the roots of trees. The
plaintiff’s house was founded upon plateau gravel at the rear and the greater
part of the flank wall, but upon an outcrop of Bracklesham-based clay at the
front. Differential settlement was therefore likely to occur in any event, even
if uninfluenced by external factors, such as dehydration by the roots. However,
such settlement would be likely to have revealed its full effect within 10
years of the erection of the house. No structural damage in fact occurred
during this period, and there was no structural damage of any significance
prior to the events of 1976.
On the basis
of those findings the judge then dealt with the law and he expressed it in this
way:
I therefore
find that the law which I have to apply to the facts of the present case to be,
that the duty in respect of the nuisance created by the roots arises if the
encroachment of those roots is known, or ought to be known, to the owner,
occupier or other person responsible for the tree and its maintenance, if the
encroachment is such as to give rise to a reasonably foreseeable risk that such
encroachment will cause damage.
That
formulation of the law, although it had been contested below, was accepted in
this court by Mr Smyth, for the plaintiff. I am bound to say that at first I
had doubts whether it was an accurate formulation of the law because of the
case of Davey v Harrow Corporation, a decision of this court
reported in [1958] 1 QB 60, which makes no reference to foreseeability as an
element in the tort of nuisance, where the nuisance is caused by the extrusion
of tree roots or branches, but on further consideration I agree that Mr Smyth
was right to accept the formulation of the law as made by the judge.
In Leakey
v National Trust [1980] 1 QB 485 Megaw LJ reviewed the whole of the law
of nuisance not brought about by human agency, and at p 522 he dealt with the
case of Davey v Harrow Corporation. He said (at D):
I have no
hesitation in preferring [that] decision as stating the law as it now is:
subject to the proviso that the duty arising from a nuisance which is not
brought about by human agency does not arise unless and until the defendant
has, or ought to have had, knowledge of the existence of the defect and the
danger thereby created.
Shaw LJ, with
some doubt, and Cumming-Bruce LJ both agreed with the judgment of Megaw LJ.
Although it was not necessary for the decision, the proviso suggested by Megaw
LJ puts nuisance by encroachment of tree roots and branches into the same
category as any other nuisance not brought about by human agency. It is
consistent with Sedleigh-Denfield v O’Callaghan [1940] AC 880 and
confines the strict liability for nuisance to cases where there has been some
non-natural user of the land as stated in Rylands v Fletcher
(1868) 3 HL 330. I would accept the proviso as stated by Megaw LJ as applicable
to the facts of this case.
Mr Smyth’s
basic submission was that there was ample evidence to support the judge’s
finding that the risk of subsidence to the plaintiff’s house was reasonably
foreseeable by the defendants. Mr Smyth submitted that it was a finding of fact
and that this court should not interfere with it. I do not think that this is the
right approach. The finding as to foreseeability was not a finding of primary
fact. It did not depend on an assessment by the judge of the reliability of the
witnesses, or upon a resolution of a conflict of evidence. It was an inference
which the judge drew from the whole of the evidence. Having read the whole
transcript, this court is in as good a position to draw inferences of that kind
as was the judge, and in some ways better.
I approach the
case on the basis of asking the question, ‘What is the proper inference to be
drawn from the evidence?’
One of Mr
Foy’s principal criticisms of the judge’s finding was that, in considering
foreseeability, he had concentrated on the likelihood of pockets of clay being
present in the subsoil and had virtually ignored the long period of drought
from the early summer of 1975 to September 1976. The evidence was that this was
quite exceptional and abnormal, as Mr Baker, the expert witness called by the
plaintiff, put it, and the probability of such a long period of drought (Mr
Baker said) was extremely remote as it had occurred only once in the last 200
years.
Mr Foy said
that the drought was an important factor which should be taken together with
the possible presence of clay in the subsoil and with the shallowness of the
foundations and the proximity of the tree to the house in considering the
question of foreseeability. He submitted that it was the combination of those
factors which caused the subsidence and that all four factors should be taken
into account when considering the foreseeability of subsidence.
The difficulty
with that approach, it seems to me, is that Mr Baker said that, even if there
had not been a drought, the tree roots would eventually have caused a
subsidence because of the existence of the outcrops of clay under the
foundations and that the drought merely accelerated this process. And Dr
Biddle, the expert called by the defendants, said that as there was clay under
the house there was a probability of subsidence that ought to be considered in
any event.
In my view, in
considering the question of foreseeability the judge was right to concentrate
on the likelihood of pockets of clay under the house and on the proximity of
the tree to the house in the light of the evidence that the roots of chestnut
trees grow as far as their height. Indeed it was accepted by Dr Biddle that he
would expect the roots of this tree to extend under the foundations of the
house and the roots would be likely to dehydrate the clay and cause the
subsidence.
So the vital
question is whether the defendants should reasonably have foreseen that there
might be pockets of clay under this house. If there were, and the foundations
were resting partly on plateau gravel and partly on clay, as was the case,
there would be a greater risk of subsidence than if the foundations were
resting wholly on clay. If the foundations were resting wholly on gravel there
would be no substantial risk of subsidence, even though the tree roots were
extruding under the foundations.
It was common
ground that the geological map showed the subsoil in the Shirley area to be
almost entirely plateau gravel with clay underneath. The section shows that the
layer of plateau gravel must have been comparatively thin, although it was
accepted that it extended probably to 10 ft to 12 ft, which would have been
sufficient to bring it well below the foundations. In any event, it is the map
itself that is of importance for this purpose, and not the section. It was
accepted that geological maps are in general very accurate and that those
concerned with foundations are normally entitled to rely on them. But there was
also evidence that, from the knowledge of surveyors, civil engineers and others
working in Southampton, there were pockets of clay in the Shirley area. These
were quite small; perhaps between five and ten sq yds in extent. But this only
added to their potential danger if they were under a house because the
foundations would not be resting on a homogeneous subsoil.
The clay found
under no 72 consisted of a uniform, fairly stiff, yellow clay with below it a
yellow sandy clay, and below that a dark mottled clay.
The pockets of
clay in the Shirley area were said by Mr Baker to be very variable and
completely unpredictable in this location. It was common ground that the only sure
method of ascertaining the existence of a particular pocket would be by sinking
a borehole, and because of the small size of the pockets as at no 72 it would
be necessary to sink one borehole at each side of the house where clay was
suspected.
Although there
were passages in the evidence of all the experts to the effect that pockets of
clay might be found under any house in Shirley Avenue and that that was a risk
that ought to be considered, they all agreed that it was unlikely that clay
might be found under any particular house. In his evidence Mr Baker was asked:
Q. Unless you happened to have done excavations
in the particular area, you would have no reason for suspecting that there was
clay under any particular house. — A. Correct.
Q. As I understand your report, and tell me if
this is right, before you started these excavations, you had expected that it
would be plateau gravel. I rather get the impression you were slightly
surprised to find that it was clay. — A. Well, with this particular property, we
had done the one next door previously, and we found clay there. So we were not
so surprised on this particular one.
Q. Next door — that put you on guard as it
were, but before you did next door, it would certainly be a surprise to you to
learn there was clay underneath these houses?
— A. It was, yes.
Dr Biddle said
this:
Q. If you had been consulted in 1974, before
there was any question of drought, and asked to advise whether trees in this
area were likely to damage adjoining houses, what would have been your
advice? What would you have done, and
what conclusions would you have drawn? —
A. Well, when asked this sort of question routinely by local authorities in the
main, I think you have got to get the best available information of the risks
pertinent to the particular area, and the source of this information is a
geological survey map. This will tell you basically, whether you are on a
highly shrinkable soil, such as London clay, which outcrops in various areas in
Southampton, whether you are on a
beds, or whether on particular sands or gravels, and I think one has to put the
problem into one of those sort of categories, and clearly this would fall into
the last category — an area where I would certainly not anticipate any
problems.
Q. Would that have been your advice if you had
been asked in, say, 1974? — A. Yes. I
would have said there was no problem in this area. It might be thought to be
necessary to take action where there are settlement risks.
He was asked a
direct question in cross-examination:
Q. Did it surprise you to find this clay here
at this depth? — A. It certainly
surprised me, yes, because my experience of geological survey maps shows they
are right in 99 per cent of cases I have investigated, and would normally give
you a pretty good idea of what you would find.
Taking the
evidence of Mr Baker and Dr Biddle as a whole, and they were the two
independent experts, a fair reading of it seems to me to show that both were
surprised at the presence of pockets of clay under no 72, and Dr Biddle, at any
rate, thought that no subsidence problem in that area was likely.
The judge
relied strongly on the evidence of Mr Cocain, the defendants’ engineer. He
dealt with it in his judgment where he said:
In fact,
however, the possibility of an intrusion of clay was known to Mr Cocain, the
city structural engineer of Southampton who, for this purpose, are the agents
of the defendants. He said that — ‘In some places in the gravel there is a
high, and in some places low, clay content, and in the Shirley library area you
might find five to twelve sq yds of clay.’
Mr Foy said
that, in that passage of the judgment, the judge appears to have misunderstood
the evidence of Mr Cocain. His evidence on this part of the case appears as
follows:
Q. Were you aware before this matter came to
light, that part of Mr Solloway’s house rested on clay? — A. No.
Q. Did it surprise you to find that out? — A. Yes, very much. In the past years I have
worked for the Southampton Council. I have been concerned with a number of
projects in this particular area — public developments, the new library and
housing projects. Generally the subsoil has shown to be gravelly, of a gravelly
nature. I should say that it varies in that in places it has more clay content
and at others less clay content. It is difficult to classify, but it is
generally very good bearing strata throughout the area. I do not recall any
particular foundation problems that we have had.
Q. Have you looked at the geological drift map
in this case, for this area? — A. Yes,
obviously when we had this problem crop up, it is the well known first routine
action.
Q. What was the conclusion you drew from
looking at the map? — A. I was surprised
at the foundation damage. Obviously I had known that it was a good gravelly
area, and as events have shown the size of the clay pocket, this has rather
been a surprise to me.
Then he was
asked to look at the map and asked this question:
Q. Would you understand from looking at that
map there was a likelihood, or possibility even, of clay being on the surface
in the vicinity of this house? — A.
Well, I think it has already been said that part of Southampton is very variable.
The conditions can vary from yard to yard, but I would not expect in this area,
to find any very bad conditions. I would not have thought there would be any
large pockets of clay. That is based on the experience I have of the area.
In
cross-examination he was asked:
Q. Well, whether there is a problem or not, one
is concerned about its existence in any quantities in the sort of areas you
would concede you have found in the past. When you talk about areas where there
was a high clay content, what is the largest you think in Shirley for example —
if you are talking about Shirley — you have found of a high clay content? — A. I have seen areas where the development
I am referring to was at the edge of the gravel outcrop area. In fact, the site
at the Shirley library; on that particular site I would say that the clay
content would have been more than 50 per cent.
Q. I am not concerned about the content, but
the area you found the clay content. What sort of area are you talking about —
an area of 100 sq yds, or less? — A. A handful of sq yds. Five to ten sq yds
perhaps — very localised.
Q. How far on average, would it be before you
found the next area of clay content? —
A. It is impossible to say.
Q. In your experience? — A. It might occur
twice in the building area. It might do. It might occur once. It might not
occur at all; but in no case in those places would it constitute a foundation
problem, because there was always a large stone content, which made the ground
a fairly stable bearing strata.
Q. So you would say that had not caused you to
have any worries about the foundations you were putting in? — A. Correct, yes.
Mr Foy said
that Mr Cocain, in those answers, was not talking about pockets of homogeneous
clay, he was talking about pockets of clay mixed with gravel or gravel mixed
with clay, and that in each case the gravel content was such that he had no
worries about the foundation; whereas, said Mr Foy, the judge seemed to think
that he was talking about pockets of homogeneous clay.
I find force
in that submission. I can well understand that the judge might have viewed Mr
Cocain’s evidence with caution because, as Mr Smyth said, it was not until
cross-examination that Mr Cocain admitted that the subsidence was caused by the
tree roots. But the judge did not deal with his evidence in that way. He dealt
with it on the basis that he accepted it. I think that Mr Foy was right in
saying that the judge did not understand the full implication of it. Mr Cocain,
like Mr Baker and Dr Biddle, was surprised at the presence of homogeneous clay
under no 72, but his evidence as to the mixture of clay and gravel in the
pocket, in my view, is crucial on the question of foreseeability.
The judge
dealt with the question of foreseeability in two parts, by dealing first with
what he called ‘the nature of the duty’ and then with its scope. In reality the
scope of the duty depends on the extent of the risk of damage and the two
should be considered together.
In Leakey’s
case [1980] 1 QB 485 at p 524 Megaw LJ dealt with this question in this way:
This leads on
to the question of the scope of the duty. This is discussed, and the nature and
extent of the duty is explained, in the judgment in Goldman v Hargrave
[1967] 1 AC 645 at pp 663, 664. The duty is a duty to do that which is
reasonable in all the circumstances, and no more than what, if anything, is
reasonable, to prevent or minimise the known risk of damage or injury to one’s
neighbour or to his property. The considerations with which the law is familiar
are all to be taken into account in deciding whether there has been a breach of
duty, and, if so, what that breach is, and whether it is causative of the
damage in respect of which the claim is made. Thus, there will fall to be
considered the extent of the risk; what, so far as reasonably can be foreseen,
are the chances that anything untoward will happen or that any damage will be
caused? What is to be foreseen as to the
possible extent of the damage if the risk becomes a reality? Is it practicable to prevent, or to minimise,
the happening of any damage? If it is practicable,
how simple or how difficult are the measures which could be taken, how much and
how lengthy work do they involve, and what is the probable cost of such
works? Was there sufficient time for
preventive action to have been taken, by persons acting reasonably in relation
to the known risk, between the time when it became known to, or should have
been realised by, the defendant, and the time when the damage occurred? Factors such as these, so far as they apply
in a particular case, fall to be weighed in deciding whether the defendant’s
duty of care requires, or required him to do anything, and, if so, what.
In considering
whether there is a breach of duty, the extent of the risk and the foreseeable
consequences of it have to be balanced against the practicable measures to be
taken to minimise the damage and its consequences.
The judge held
that intrusions of clay were likely in the Shirley area. With all respect to
the judge, I cannot, on the evidence, accept that finding. I think that the
possibility of an intrusion of clay under no 72, which is the real question,
was unlikely. I would hold that it was no more than a vague possibility, not a
real risk in the words of Lord Reid in the Wagon Mound (No 2) [1967] 1
AC 617, but assuming that there was a real risk or chance, I would say that it
was an outside chance and that outside chance has to be balanced against the
practical steps which could reasonably have been taken by the defendants to
minimise the damage. At first the judge found this an insuperable difficulty.
He said:
In these
circumstances, Mr Foy for the defendants submits that this would present the
defendants with a problem which would be insuperable without a very great
expense since in practice, every house in the street, and no doubt other houses
in similar tree-lined roads where similar circumstances
located, or at least the nature of the subsoil ascertained.
He further
submitted that the alternative would be to cut down all of the trees which were
potential candidates for causing root damage, and refrain from planting trees
in streets in case they gave rise to liability. He submitted that the proper
conclusion of these facts was that it would not be reasonable in all the
circumstances to require the defendants to abate the nuisance or to make them
liable for the damage consequent from the failure to abate, and that in
accordance with the principle enunciated in the Leakey case by Megaw LJ,
this gave rise to a situation in which the proper consequence was that the
individual householder should each accept such burden as might exist in respect
of their own property.
The judge
eventually dealt with the problem in this way. He said:
It may well
be, and I would so assume in the absence of evidence, that many of the houses
could be eliminated as the subject of risk, either by reason of their position
in relation to the adjacent trees, or by reason of the nature and size of the
tree — or for other reasons. It may also be that in discharge of the duty which
I have found to exist, the appropriate steps to eliminate or reduce that risk
might involve some form of co-operation between the house owner and the
defendants. Had the defendants considered the problem, and approached the plaintiff
in an attempt to find an agreed solution, it may be that this would have been
sufficient to discharge the duty. In the event, they did no such thing, and in
failing to take any steps I find they were in breach of their duty.
In my view
there is no reason to suppose that many of the houses in Shirley Avenue could
be eliminated from this risk. We were told that there is an avenue of trees all
along that road and the evidence was that pockets of clay might exist anywhere
in Shirley Avenue. All the householders, it seems to me, would have to be
approached, not only in Shirley Avenue but in any other street in Hampshire
where there are trees adjacent to houses.
The judge said
that such costs as might be involved should be regarded as part of the cost of
maintenance of trees to the public good. ‘In any event,’ he said, ‘trees
require to be examined, and from time to time lopped or topped, and generally
kept in good order, and such additional costs as there may be in respect of
trees whose roots may present potential risk to adjacent property owners are in
my view, in the absence of any specific evidence on the subject, properly to be
regarded as part of the general maintenance costs, and are unlikely to add
significantly to such costs, having regard to the comparatively rare instances
in which the problem is likely to arise.’
Felling and
lopping of trees, as suggested by the judge, might give rise to all sorts of
complaints and difficulties, quite apart from its interference with public
amenities, and in the end such action might well not be appropriate, because
the evidence was that the only effective method of locating the pockets of clay
would be by sinking boreholes at every house adjacent to a tree.
Mr Smyth did
not go so far as the judge. He submitted that the defendants having done
nothing, the onus was on them to lead evidence to the effect that remedial work
was not practicable. He submitted that, at the very least, the defendants
should have considered and discussed the question, and there was no evidence
that they did; that they should have then circularised all householders whose
houses were adjacent to trees, pointing out the dangers and asking them to pay
for, or share, the costs of boreholes.
It seems to me
that that evidence is not necessary in a matter of this kind. The expense would
be considerable. Common sense tells that action of the kind suggested by Mr
Smyth would be likely to cause more problems than it solved. Householders
circulated in that way would be likely to suffer apprehension for the value of
their property, and probably with no reason. The consequences of such
circulation, it seems to me, are unpredictable and unsatisfactory. Balancing
the risk of pockets of clay under no 72 with the steps necessary to deal with
that risk, in my judgment there was no breach of duty by the defendants in this
case and so no nuisance.
I reach this
conclusion with regret.
At the end of
his judgment, the judge, having considered the question of foreseeability and
the reasonableness of the steps needed to abate or remove the nuisance, said
that ‘the real question was on whom should the loss fall?’ and concluded that
‘the loss should properly be a charge on the public, for whose benefit the tree
was maintained and not on the individual who has suffered the damage.’
There is much
to be said for that approach, but it is not the law. There being no breach of
duty by the defendant, the plaintiff’s claim must, in my judgment, fail and accordingly
I would allow the appeal.
Agreeing, SIR
DAVID CAIRNS said: I add a few words because we are taking a different view
from that taken by Stocker J.
Since the
subsoil at Shirley was almost entirely gravel, since there was no indication on
the geological map even of pockets of clay, and since there was no experience
of damage caused to the structure of any of the houses in Shirley Avenue by the
roots of trees since the houses were built in 1922, it appears to me not
surprising that the county council clearly never directed their minds to the
question of whether any particular house in that road was liable to be damaged
by such roots. If they had considered the matter, I am of opinion that they
could have reasonably taken the view that any risk of such damage was so remote
that it could be disregarded. To say that a risk of damage is reasonably
foreseeable means that it is foreseeable not merely as a theoretical
possibility but as something the chance of which occurring is such that a
reasonable man would consider it necessary to take account of it. The risk of
being struck by lightning when one goes for a walk is not a reasonably
foreseeable risk. I should be prepared to hold that the risk in this case was
not a reasonably foreseeable risk.
If, however,
it could be said to be a reasonably foreseeable risk, I am satisfied that it
was a risk such that the cost and inconvenience of taking any effective steps
to remove it or reduce it would be quite out of proportion to that risk. There
is nothing in the evidence to show that 72 Shirley Avenue was any more at risk
than any other house in the avenue. Nor is there anything to show that any
operation on the trees, short of felling them, would have made the roots safe
if there were exceptionally dry weather and if the roots of any particular tree
were passing through clay.
Clearly it
would have been unreasonable for the council to remove all the trees in the
avenue and it is unlikely that Shirley Avenue was the only road in the area
where there were trees in proximity to houses. The alternative would have been
to make an examination of the subsoil of every house which might possibly be at
risk by boreholes in order to see whether the ground there was of clay, gravel,
or a mixture of both. Obviously a number of boreholes would have been needed
close to each of the houses. It would all have been of great inconvenience to
householders and the making of any proposal for it would have been likely to
cause considerable anxiety to them. The value of the houses might well have
been reduced by reason of the operation.
For those
reasons and those given by my Lord, I agree that the appeal should be allowed.
Also agreeing,
STEPHENSON LJ said: I have reluctantly come to the conclusion, after the great
assistance received both by the judge and by this court from counsel on both
sides, that the appeal must be allowed for the reasons given by my Lords.
If, as is
suggested by the language of Lord Goddard CJ, giving the judgment of this court
in Davey v Harrow Corporation [1958] 1 QB 60, all the property
owner had to prove was a nuisance causing actual damage by the encroachment of
the appellant council’s tree roots, he would be entitled to retain his damages.
But in this court Mr Smyth, for the respondent, has abandoned that contention
and concedes, rightly in my judgment, that the statement of the law in Davey’s
case is subject to the proviso put upon it by Megaw LJ in Leakey v National
Trust, and rightly explained and applied by Stocker J. So there are two
questions to be considered: (1) was there a foreseeable risk that the
encroachment of these tree roots would cause damage to the respondent’s house,
and (2) were there any reasonable precautions which the appellant could have
taken to prevent or minimise that risk?
The second question takes that form because the appellant took no
precautions.
It is common
ground that the respondent cannot succeed in getting a favourable answer to the
first question unless he can prove that the appellant ought to have foreseen
that there was a real risk
On the
evidence analysed by my Lord, Dunn LJ, I am willing to assume that the expert
evidence entitled the judge to find that that risk was more than a mere
possibility which would never occur to the mind of a reasonable man, in the
oft-quoted words of Lord Dunedin in Fardon v Harcourt-Rivington
(1932) 146 LJ 391 at p 392, and which would therefore require no extraordinary
precautions. But granted there was a real risk, reasonably apparent to the
appellant’s engineers, if they had thought about it, of clay under the
respondent’s house, I cannot agree with what I think was the judge’s opinion
that the appellant could effectively discharge its duty by investigating
comparatively few properties and trees, and perhaps approaching a few property
owners, or felling or lopping a few trees, at little expense. I do not think it
needed evidence to decide that to have prevented or minimised the plaintiff’s
damage would have required correspondence with many property owners in the
county, wholesale inspection of and boring under properties, and the felling of
many trees, which would have put the appellant to very great expense and
produced many complaints from property owners upset by warnings of dangers
which might not exist and from a wide public deprived, perhaps needlessly, of
the amenity provided by trees like those lining Shirley Avenue.
Such
precautions would not, in my opinion, be reasonable and no less would have been
required, without exceptional good luck, to discover and deal with the pocket
of clay which unhappily underlay a crucial part of the respondent’s house
before the abnormally long, dry season of 1975-1976 made it too late to stop
the subsidence and damage.
I therefore
feel, as did the judge at first, that this submission of Mr Foy’s, for the
appellants, is not only cogent but insuperable, and I accordingly agree that
the appeal succeeds.
The appeal
was allowed with costs.
