The content of the duty and the relevance and application of the Guideline
54The content of the duty is, in my view, reflected by the Guideline which specifies ground clearance with the evident purpose of eliminating the risk of contact by normal use of the ground under the line. I take the Guideline to constitute an assessment by electricity authorities, including Country Energy, of what reasonable care requires. Because high vehicles can and do lawfully travel along public roads the clearance for lines along such roads is set at a level which will prevent contact between such vehicles and the lines. Where the land does not amount to a public road but can be traversed by vehicles that travel along public roads, a judgment is, according to the Guideline, called for. Although the journal article referred to by Dr Grantham had limitations, which were expressed in the article, it constituted a useful reminder of the substantial risk of harm occasioned when persons, particularly those working on rural properties, are working in the vicinity of powerlines. I infer that Country Energy was well aware of such risks, particularly on those properties, it being the electricity authority for country New South Wales.
55Mr Windsor submitted that it was implicit in 2000 that the type of vehicles to which the table in the Guideline related were vehicles with a maximum height of 4.6ms and that the reference to "vehicles of unusual height" in the note to the Guideline would, accordingly, not be "vehicles of unusual height". He contended that, in these circumstances, a ground clearance of 5.65m was ample to allow such vehicles to pass under the line and accordingly there was no negligence. I do not accept this submission, in part because the stipulation of 6m in the design drawing would appear to involve the judgment called for by the note, and have been exercised on the basis that just such vehicles would be likely to pass under an overhead line on the property. Furthermore, I accept the evidence of Dr Grantham that a B-double, or other vehicle of the height of 4.6m would be regarded as being of "unusual height" for the purposes of note three in the Guideline. I do not accept Dr Barr's evidence that the expression "unusual" vehicles in this context does not apply to those permitted on public roadways or that it typically applies to mine sites.
56Mr Windsor submitted that, since the plaintiff tendered the 2002 audit document referred to above as a business record, he ought be taken to accept its accuracy and that, accordingly, I ought find that the power line was the "correct clearance" from the ground. It is not clear whether the "correct clearance" said to have been achieved was 6m, in accordance with the approved design, or 5.5m in accordance with the Guideline. Furthermore there is no evidence that an actual measurement was taken in the course of the audit, or, if so, what the measurement was. The detail of the document does not permit me to draw the inference as to the ground clearance as at 18 June 2002. Nor does it permit me to draw the inference that it was constructed in accordance with the design drawing, or indeed any other particular standard. I would not draw that inference absent evidence from Mr Gray or Mr Taylor. I infer, since they were not called, that their evidence would not have assisted the case of Country Energy: Jones v Dunkel [1959] HCA 8; 101 CLR 298. All I would draw from the document is that there was no visible problem with the power line that could be detected absent measurement or survey.
57Mr Windsor also submitted that the power line was relevantly constructed in accordance with the Guideline because, at the point of impact, its ground clearance was 5.65m. He said that it was not to the point that the ground clearance happened to be 5.35m some 24m south east of that point, at a location between the track and a stock yard fence. I do not accept this submission since Country Energy itself had applied the Guideline to set a design clearance at 6m and therefore can be taken to have made the judgment in accordance with the note that additional ground clearance was required.
58Mr Windsor contended further that the design parameter's allowance for line clearance of 6m does not mean that the line should, or must, have a clearance of 6m. Rather, he submitted that what the designer was doing was to recognise that the ground profile will change across a span as land is never exactly flat and that the direct aim of specifying 6m was to ensure a minimum clearance of 5.5m. Dr Barr provided some support for this hypothesis by deposing that designers "normally allow" an additional 0.5-1m of ground clearance to cover small undulations. Indeed he said that he and his staff had often done so when designing lines. However, there is no evidence that this is what occurred in the present case. I am not prepared to accept this submission without evidence from Country Energy as to the thought processes of its designer, or the person who approved the design. If evidence to that effect had been given, it would have assisted Country Energy's case. The inference I draw is that if such persons had been called their evidence would not have assisted Country Energy's case.
59In my view, the duty of reasonable care owed by Country Energy to persons such as the plaintiff required it to erect the line at a height of at least 6ms, at which such persons using the property for the purposes which were in reasonable contemplation for such a property would not come into contact with it for the following reasons:
(1)the level generally specified by the Guideline for land other than public roads was 5.5ms;
(2)the obvious and foreseeable use of the properties in the part of New South Wales where Wapweelah is situated was as large-scale grazing land which as a matter of almost nigh inevitability requires the use of large, high vehicles;
(3)there is no particular reason to distinguish the height of power lines on the roads in those areas from the height of power lines on properties in those areas since the highest vehicles that traverse the roads can be expected to be engaged in deliveries of stock to such properties;
(4)inspection of the property would have shown that there were wheel tracks along the dirt road along the path which the power line generally followed and that it could be expected that that road was used by heavy vehicles; and
(5)Country Energy, following consultation with Mr Ridge and inspection of the property, designed the line to have a ground clearance of 6 m.
60A reasonable person in the position of Country Energy would have taken that precaution because of the following three matters (each of which I am obliged to consider under s 5B(2) of the Civil Liability Act 2002 (NSW)). The first matter is the likely seriousness of the harm (death by electrocution or serious electric shock). The second matter is the burden of taking such precautions, which, having regard to the design of the line by Country Energy which specified a ground clearance of 6m, I do not consider to be onerous. The third matter is the social utility of the provision of electricity, being the activity that created the risk of harm, including on country properties to facilitate their use as productive producers of primary produce.
61I am also obliged to consider, for the purposes of s 5B(2)(a) of the Civil Liability Act the probability that harm would occur if care were not taken. Contact between a person or a vehicle and an uninsulated power line can be fatal, or cause serious injury, if there is direct contact between the line and a person or if the person is in the vehicle and relevantly becomes a conductor of the electricity in the line. Sufficient ground clearances are the usual means of providing for separation between persons and vehicles on the one hand and lines on the other. If ground clearances are not sufficient, then there is a prospect of harm if someone in a high vehicle passes under the line. The prospect of harm is greater if the load of the vehicle has the effect of making it higher, or if a person or animal is upright above the height of the vehicle. The probability of an incident such as occurred in the present case might be regarded as low in an overall sense, simply because of the number of factors that brought it about, some of which were a matter of chance (for example that the relevant sheep was in the corner of the A-trailer rather than the B-trailer or that the plaintiff was 187cms tall). However, the same might be said of any insufficient ground clearance where the traffic underneath is likely to be relatively infrequent. In my view, the risk of harm required the reasonable precautions outlined above to be taken, even though the probability that harm would occur if care were not taken was relatively low.
62In the absence of evidence from Country Energy to the contrary, I take the design ground clearance referred to in (5) above to be Country Energy's proper assessment of the minimum reasonable ground clearance for this site, having regard to the land use and the matters referred to in (1) to (4) above. It may be that reasonable care required the ground clearance to be 6.7ms having regard to factors (2), (3) and (4) above. But it is not necessary to decide this question since the plaintiff put his case, and Mr Ridge put his claim for contribution, on the basis, which was accepted by all three experts in concurrent evidence, that the accident would not have happened if the ground clearance had been 6ms at that location.
63I note that Mr Carmody considered that even if the ground clearance at the lowest point of the catenary had only been 5.5ms, this would have been enough to avoid the accident at the point at which it was located. Although this observation may be sufficient to deal with the instant case, I am satisfied that reasonable care required greater than 5.5m ground clearance for this power line.
64This formulation of the duty does not include any element of "reliance" on the part of the plaintiff that a statutory function will be exercised for his particular benefit: Romeo v Conservation Commission (NT) [1998] HCA 5; 192 CLR 431 at [20] per Brennan J.
65Country Energy's failure to take the reasonable precaution of constructing the line so as to give a ground clearance in accordance with its design of 6ms was negligent and caused an immediate risk of harm to persons passing under the line (Cf. Sydney Water Corporation v Turano [2009] HCA 42; 239 CLR 51 at [49]). That the risk of harm did not ensue for a period of eight years following its construction was a matter of chance and neither undermines the risk of harm, nor its seriousness.
66In so far as any case was pressed against Country Energy that it should have erected an additional pole or moved the pole that was there away from the gate to the sheep pen, I do not consider that case has been made out. Country Energy installs power lines for the long-term and cannot be expected to assume, either that gates or fences will be moved, or that they will not be. Although there was evidence that established that the double silver gates through which the sheep were unloaded on the day of the incident were not functional at the time the power line was installed, I do not consider this to be a material factor.
67Although it was suggested that such duty required it to position the line at a distance from the dirt road, I do not consider that reasonable care required it, since the line of such dirt roads can change over the years, although it had not changed in the present case.