37 I should at this stage say something about the sign which the plaintiffs submit should have been erected on the northern shoreline of the lagoon. I do not know, nor was it made clear by the evidence, what is meant by the words "deep holes" as used in the sign shown in exhibit B. There may have been deep holes in the lagoon in 1975 when the sign was erected. To refer to that part of the Terrigal Lagoon where Anthony drowned as having "deep holes" seems from the evidence to be incorrect. The extent of any hazard in the lagoon was best described by Mr Collachor as follows:
"Q. Have you noticed anything about the surface of that lagoon under the water?
A. Well it goes from shallow to deep, but it is not a regular gradient in parts.
Q. Have you noticed anything about what is on or in the surface of the bottom of the lake?
A. Some parts of it become a hole, or it falls away quite quickly.
Q. Have you observed or felt holes in that area?
A. I have in the past walked across that section and sometimes you fall down quite quickly or your leg has gone into a deeper section unexpectedly.
Q. It is not all flat and undulating?
A. It doesn't have a gradient like a soup bowl where it goes down gradually or at a predetermined grade and goes up the side of the bowl. I don't think that cross-section there is like that.
Q. What is it like?
A. Well, it is irregular, it can move out at a fairly gentle gradient, then go down quite quickly, but that can also change over time." (T.47)
38 If that is the hazard to which the sign was referring, then it was misleading. What Mr Collachor appears to be describing is the sort of unevenness one would expect on the bottom of most naturally occurring waterways. In any event, as the evidence of Mr Lyon made clear, the scenario which Mr Collachor described did not exist on the day of the accident for a person such as Anthony entering the lagoon from the north shoreline and progressing towards the south. It follows that there is considerable force in the defendant's submission that the particular hazard referred to in the sign was not causally related to Anthony's drowning.
39 There was no issue at trial that the defendant as a public authority vested with the statutory care, control and management of the lagoon owed a duty to take reasonable care for Mrs Saad and Anthony. The real question, however, was what was the content or scope of that duty of care?
40 The starting point for such an inquiry is to look at the nature of the danger assessed prior to the accident with reference to such matters as the functions of the public authority, the obviousness of the danger and the care ordinarily exercised by members of the public (Gummow J Vairy v Wyong Shire Council (2005) 223 CLR 422 at [79]).
41 Looking at Terrigal Lagoon prospectively, that is before the occurrence of the accident, the "nature of the danger" to which Anthony was exposed was one common to almost every natural waterway, ie that as one moved further away from the shore it became deeper. That a child who was not a strong swimmer might get into difficulty if he walked or swam beyond his depth was a danger of the most obvious kind.
42 Gleeson CJ and Kirby J commented to that effect in Vairy:
"[5] Both cases involve the tortious liability of public authorities responsible for the areas in which the diving accidents occurred. They were areas of recreational land, open to the general public. Many forms of outdoor recreation involve a risk of physical injury. In some cases, while the risk of injury may be small, the consequences may be severe. Swimming is a popular recreational activity along the Australian coast. It involves certain risks, and sometimes results in injury, or even death. The level of risk varies according to the locality, the conditions at any given time, and the capabilities of the swimmers. Short of prohibiting swimming altogether, public authorities cannot eliminate risk. A general prohibition in a given locality maybe a gross and inappropriate interference with the public's right to enjoy healthy recreation. Swimmers often enter the water by diving, or plunging headfirst. This also, is risky. Diving into water that is too shallow, or diving too deeply into water, in which only a shallow dive is safe, can have catastrophic results. Again, short of total prohibition, it is impossible to eliminate such risks; and no-one suggests that swimmers should be prohibited generally from entering the water head-first.
[6] In each case, the breach of duty alleged was a failure to warn. A defendant's duty of care is owed to an individual plaintiff, but it is a duty to do what is reasonable in all the circumstances. The fact that a defendant is a public authority with the responsibility of managing large areas of recreational land may be a circumstance material to a judgment about the reasonableness of its conduct. As Brennan J pointed out in Nagle , the duty owed to the plaintiff is, in the ordinary case, owed to him or her as a member of the public. The nature of the premises, the right of public access, will have an important bearing on what reasonableness requires by way of a response to risks associated with the use and enjoyment of the land.
[7] Warning signs only serve a purpose if they are likely to inform a person of something that the person does not already know, or to draw attention to something that the person might have overlooked or forgotten. The obviousness of a danger can be important in deciding whether a warning is required. Furthermore, a conclusion that a public authority, acting reasonably, ought to have given a warning ordinarily requires a fairly clear idea of the content of the warning, considered in the context of all the potential risks facing an entrant upon the land in question. When a person encounters a particular hazard, suffers injury, and then claims that he or she should have been warned, it may be necessary to ask: why should that particular hazard have been singled out? If a public authority, having the control and management of a large area of land open to the public for recreational purposes, were to set out to warn entrants of all hazards, regardless of how obvious they were, and regardless of any reasonable expectation that people would take reasonable care for their own safety, then signs would be either so general, or so numerous, as to be practically ineffective. If the owner of a ski resort set up warning signs at every place where someone who failed to take reasonable care might suffer harm, the greatest risk associated with downhill skiing would be that of being impaled on a warning sign.
[8] Observation confirms that, in this community, it is accepted that there may be some circumstances in which reasonableness requires public authorities to warn of hazards associated with recreational activities on land controlled by those authorities. Most risky recreational activities, however, are not the subject of warning signs. It is impossible to state comprehensively, or by a single formula, the circumstances in which reasonableness requires a warning. The question is not answered by comparing the cost of a warning sign with the seriousness of possible harm to an injured person. Often, the answer will be influenced by the obviousness of the danger, the expectation that persons will take reasonable care for their own safety, and a consideration of the range of hazards naturally involved in recreational pursuits."
43 In view of those considerations, why did the defendant have a duty to warn against a risk which was so obvious? Alternatively, if as the plaintiffs contend the defendant had a duty to warn of the risks associated with the increasing depth of the lagoon as one moved from the northern shore, why did it not have a duty to warn against any other perils associated with the entry of persons into naturally occurring bodies of water?
44 It should be noted that the defendant did not put Anthony in harm's way in the sense that it invited or encouraged him to use the Terrigal Lagoon. It is of no relevance to that issue that the defendant could have prohibited him from entering the water or could have provided a warning that the depth of water in the lagoon varied, particularly as one moved away from the shoreline. Nor was the defendant's control over the lagoon such that it could be said to have created the risk to which Anthony was exposed on the day of his drowning. The gradual increase in depth of the lagoon as one moved from the shoreline was a natural phenomenon although the creation of the channel may have been due in part to the opening of the berm from time to time. It seems to me that the control exercisable by the defendant over Anthony and his mother on the one hand and the lagoon on the other did not rise to such a level that the content of the duty of care which it owed to them should have included an obligation to issue the sort of warning for which the plaintiffs contend. (Vairy [92])
45 The factual background to this case is rather similar to that which was considered in Mulligan v Coffs Harbour City Council [2005] 223 CLR 486. In summarising the conclusion of the trial judge Gleeson CJ and Kirby J said:
"[6] … There were features of the place where the appellant was swimming that were distinctive, but the conditions that led to the appellant's injury were not unusual. The danger that materialised was one that exists at virtually every Australian beach, and in most waterways. It is one of many dangers involved in swimming. It is difficult to see how such common dangers can be addressed by particular warnings at particular locations."
46 On the limited information available, what caused Anthony's death was the gradual increase in depth of the lagoon as one moved from the northern shore. That circumstance as Mulligan points out is a feature of virtually every Australian beach and most waterways. It is one of the many dangers involved in swimming, particularly where children are involved. I am not persuaded that the content or scope of the duty of care owed by the defendant to the plaintiffs included an obligation to erect a warning sign which referred to an increase in depth of the lagoon.
47 If one approaches the case from the point of view of breach of duty of care, as distinct from whether the duty of care required such a warning, the same result is arrived at.
48 When considering questions of breach of duty one is required to follow the mode of reasoning set out in Wyong Shire Council v Shirt (1980) 146 CLR 40. The possibility of a young child such as Anthony drowning was reasonably foreseeable. In determining what response if any was required to that foreseeable risk the Court is to take into account such factors as the magnitude of the risk, the degree of probability of its occurrence, the expense difficulty and inconvenience of taking alleviating action and any other conflicting responsibilities of the defendant. The Court has to then balance those considerations.
49 Such an approach, however, is not to be applied inflexibly. In Mulligan the following observation was made:
"[2] … Moreover, depending upon what may be involved in the concept of conflicting responsibilities, in some contexts, of which the present is an example, to treat what was said in Shirt as an inflexible formula could produce a distinctly unreasonable result. Where the suggested alleviating action is putting up a single warning sign at a particular location in a public recreational area, the expense, difficulty and inconvenience involved may be made to appear negligible. The more important question may be why a public authority would choose to single out that particular spot, or that particular risk, as the subject of a warning. …
[3] This Court recently said, in Thompson v Woolworths (Q'land) Pty Ltd [2005] HCA 19 that reasonableness may require no response to a foreseeable risk, and pointed out that householders do not ordinarily place notices at their front doors warning entrants of all the dangers that await them if they fail to take reasonable care for their own safety. That observation was not the product of a calculus; it was simply a statement about community standards of reasonable behaviour." (Gleeson CJ, Kirby J)
50 Hayne J made similar observations in Vairy:
"[105] … Resolving that question, a question of fact, hinges critically upon recognising that what has come to be known as the "Shirt calculus" is not to be undertaken by looking back at what has in fact happened, but by looking forward from a time before the occurrence of the injury giving rise to the claim. The several questions described by Mason J in Wyong Shire Council v Shirt are to be asked and answered with that perspective. …
[107] Diving or plunging into water carries a risk of catastrophic spinal injury if the water is too shallow. That risk is always present, and foreseeable, wherever there is a body of water into which someone may dive or plunge. The diver may strike his or her head on the bottom or on some obstacle in the water. But it does not follow because an injury is foreseeable that the person who has the care, control and management of the land from which a person may enter the water in that way must in every case take steps to warn against, or prohibit, such conduct."
51 Tragic though the facts of this case are and despite the sympathy which I have for the terrible loss suffered by the plaintiffs, the case law and the facts of the case compel a verdict for the defendant. I am not persuaded that the content of the duty of care owed by the defendant to the plaintiffs included a requirement to erect a warning sign which referred to an increase in depth of the water in the lagoon and which contained a reminder that children swimming in the lagoon should be closely supervised. These were features which exist in almost every naturally occurring body of water where swimming takes place.
52 I am not persuaded that the failure to erect such a sign constituted a breach of duty of care by the defendant. It was reasonable for the defendant to expect that members of the public such as the plaintiffs would be aware of such matters. In fact the second plaintiff was so aware. The proposed sign would not have provided any information which she did not already have.
53 Finally, I am not persuaded that the absence of the sort of sign proposed by the plaintiffs caused Anthony's death. If it be the fact that there were deep holes in the lagoon, they played no part in his death. The plaintiffs' case fails to satisfy the test of "factual causation" referred to in s5D CLA.
54 I do not propose to analyse in any detail the application of ss 5F, 5G and 5H CLA to the facts of this case. It seems to me that the wording of those sections sits somewhat uneasily with a situation where plaintiffs are claiming in respect of the death of a third party. For the reasons indicated, however, it is clear that the risk of Anthony drowning was an "obvious risk" as defined by s5F so that s5H might have applied to the facts of this case.
55 Although I have found against the plaintiffs on the issue of liability, it is necessary for me to assess damages in case that finding is overturned on appeal.