ROSS CREEK RESERVOIR.
At last night's meeting of the City Council t'le question of the safety of the reservoir was brought under notice by the following letter from Mr E. S. Clarke, clerk to the Maori Hill Borough Council:—"ln order to allay the appreheusion felt by the residents of Woodhaugh as to tho safety of the Ross Creek reservoir, I have been instructed to ask whether it is the intention of your Council to allow it to be filled again without t dung any steps to ascertain whether such a course would be safe, and, if eo, to ask that the "rounds on which the opinion as to its B3curity is based should be made public." Mr James Allen, M.H.R., wrote from Wellington, as follows:—"My attention has been drawn to the leak in the Leith reservoir, and I have been asked to take steps to get the Government to appoint an i ispector or engineer who should thoroughly i ivestigate the matter. Before doing so I ahould bo glad to know what the City Council have to say about the leak, and wiiether they would favor an inspection by tiovernment. An early reply will oblige." The following report from the City engineer, Mr S. 11. Mirams, was read : " As the question of the alleged leak at the Rosa Creek reservoir will, I understand, come before you to-night, I beg to report that bo far I have observed no change in the condition of affairs at tho reservoir since the date of Mr Hay's report in September, 1380, with the exception that the flow or soca'lecl leak at the tubble wall appears again to have slightly divided. _ To report more fully will, of course, necessitate an extended investigation. The amount of water discharging at the face of the rubble wall into the creek has always been a variable quiutity, depending largely upon the state of the weather. To-day the How is at the rite of 7,05Ggal per day with a depth in reservoir of 23ft Sin. To arrive at a definite conclusion as to whether the averageflow is increasing wonld require a series ol mcieurcments for comparison with those taken formerly, but I see nothing at present to warrant such a supposition. The earliest measurement that I have on record is that observed by Gillies, fc'ie caretaker, on Bth April, 1875, which gives 8,020 gallons per day, with a depth in reservoir of 25ft Bin. I have always expressed the opinion to the Council that the water complained of does not come through the puddle wall of the embankment, and this view is supported by Professor Black did Mr Hay. The lapse of time is another Indication to my mind that the puddle wall ia intact, as a constant run of this description would, I consider, gave unmistakable evidence that something was wrong were it percolating through the puddle wall. I may remind the Counoil that the embankment is ■trongly placed against the natural spurs of the hill, which act as a buttress on either side. I see, therefore, no cause for alarm as reepects the stability of the embankment; but with the view of allaying the apprehensions excited by the calamitous disaster at Johnstown, I would recommend that the reservoir should not be filled for the present to a greater height than the 38ft line. This would bo 10ft Sin below the top level line. By keeping the water down to this lower level the loss of storage would be about twofifths of the holding capacity of the reservoir, but this could be dispensed with at any rate during the winter months." Or Kimbkll moved that tho correspondence and the report be referred to the Water Committee, with power to act. The dam which was said to bs dangerous rested •gainst a natural wall, and the so-called leak was doubtlesa caused by filtration. There was not the slightest of a Blip taking
place. Rut it wan tho ( 'nunc il'.-i duty to net the iniudu of people tit rest, and instead id wasting money on the wall the reservoir should bo kept low. Then careful observation should he made of the amount of filtration flowing from the culvert, and the eatetaker might register daily, with the aid of a reliable water-guagc, the volume of the flow. The caretaker should also have a proper register book in which the depth of the reservoii might bo recorded, and he sho.dd register the rainfall. The rainfall, he held, had more to do with the leak than the reservoir. The caretaker should also have, a barometer for the purpose of showing the state of the weather at the reservoir, and also to show if there was any rain falling a few miles away. It was necessary that a larger by-wash should be made or an extra one provided, so that the water might he taken from the income at the head of the reservoir. If these things were done, the public would have no cause for alarm. Cr Haynes seconded the motion.
Cr Barron said that the whole question was before the Council three years ago. They then took all the trouble possible, and spent a lot of money in getting experts to give evideneo and find out all about this particular matter. There had been no alteration in the so-called leak since then, neither was there any alteration for the last twenty years. He said that on the authority of Mr Gillies, the caretaker. Sometimes the flow was a little more, sometimes a little less ; but it had never exceeded a certain quantity for the last twenty years. There might be something in the fact that Mr Hay some years ago said it would he a wise thing for the Council to make an extra bywash when convenient. That might be, but the time had not arrived, and if the Water Committee at any time had a sufficient amount of money to expend in this way they would expend it, although it was not admitted, either by the engineer or by the Water Committee, that_ there was any immediate necessity for it. If the by wash was made it would be simply for the purpose of preventing a chaneo waterspout, a great flood, or something else that might never occur, lie had heard that some people could not sell their property on account of the alleged danger of the reservoir, but if those people really knew the reason why their property was reduced in value they would say that the cause was Mr Clifford, and not the Council. Along with the mayor and members of the Water Committee, he had visited the reservoir the other day, and after carefully going over the whole ground they had concluded, looking at the immense strength which nature had given to this bank through which the leak was said to How, that it was impossible that a disaster could occur. But supposing the worat were to happenthat the reservoir were to break the water would go down the gully, and by the time it came to the end of it the water would have spread all over the Hat; _ and, looking at it from a common sense poiut of view, he did not think anybody would get wet at all.—(Laughter.) If any man was in his bed the water would not get up to him. The scare was raised for another purpose than for the public good, and hv had no hesitation in saying that the Committee would not advocate spending any move money on the reservoir. Cr Lke Smith said that at the north end of the town there was a good deal of consternation in regard to thi3 affair. If the reservoir did burst it would make the Corporation liable for enormous damages. He would move that the matter be referred to the Water Committee with power to act in regard to giving Mr Allen power to arrange with the Government in the matter of getting an expert to report. Cr Solomon was of opinion that if this embankment were carried away the Council would be held liable for every sixpence of damage that was done, as it would be shown that they had been repeatedly cautioned of the danger. There was no doubt, also, notwithstanding the opinion of Cr Barron, that the bursting would in all probability entail serious loss of life. He thought, considering how large a matter it was, that the Council should be absolutely satisfied, so far as they could be satisfied of anything human, that this thing was absolutely and perfectly safe, If any steps could be taken, it was the duty of the Council to take those steps no matter what the cost. It was not a matter of much consequence whether it cost LSO or L.">oo. Cr Barron said that, according to_Mr Mirams's report, the necessary alterations would cost L;i,000. Cr Solomon said that whatever it cost it was a duty which the Council owed to the citizens, and to the persons living in the neighborhood of the reservoir to place the safety of the embankment beyond the slightest shadow of a doubt. It would be very desirable if they could get the opinion of an expert—one not belonging to Dunedin at all a man like Mr Higginson, for instance.
Cr Carroi.t, would not stand in the way of obtaining information, but considered it would be bo much money thrown away. He had been a member of the Council for twenty years, and no expert could give an opinion better than the caretaker, who had been on the ground for that length of time. Cr Cramosd had been a constant visitor at the reservoir in every season of the year, and could not for the life of him see that the flow was getting larger, lie certainly did not see that the Corporation should be hoodwinked by an individual, nor that Mr Allen should be called upon by that individual to write to the Corporation. He hoped the residents of North Dunedin would at the public meeting next night treat the individual in the way he deserved. He hoped that the Council would "sit on" anything like a proposal to bring an expert from Wellington. The Mayor said it was his opinion that Nature had made the reservoir almost without their assistance. His impression was that it would take something that was never seen in New Zealand to make the reservoir give way. He thought that if the Council allowed only 3Sft of water to remain in the reservoir during the winter, all thoughts of danger would be dissipated. It would be very injudicious on the part of the Council to call in professional experts on the matter.-(Hear.) They (the Council) had thrown away thousands of pounds at the instance of letter-writers to the Press. It was reasonable to suppose that if a leak existed in 1875 of 8,000 gallons in twentyfour hoars, it would have now increased to ten times that amount—in fact, would have washed the bank right away—but in 1889 the outflow was something li;se 7,000 gallons. He thought that if the Council adopted Mr Mirams's suggestion it ought to satisfy the residents of Woodhaugh. There were about S,ooo,ooogal of water in the reservoir now, and if that water was let out it would extend to the Lsith bridge, covering a depth of only three inches. The reservoir at Johnstown was three miles long, one and ahalf miles broad, and about 40ft deep. Mr Mirams had estimated what quantity would bo in it when full, and what quantity would bo in ours when full. The Dunedin reservoir would hold 50,000,000ga1, but the Johnstown reservoir contained 730 times as much. He did not think, comparing the one with the other, that there was the least to be feared from the Woodhaugh reservoir. Cr Cohen' asked the chairman of the Water Committee if, in the event of the Ross Creek reservoir being emptied the Silverstream one CDuld be relied on to supply the City. Cr Barron said he would not like to commit himself by saying that tho Silverstream would be sufficient at this time of the year. Cr KimbelFs motion was carried, and it was agreed to adopt the engineer's suggestion that the water in the reservoir should not bp allowed to exceed the 38ft mark.
It was also agreed to write to Mr Allen after next meeting informing him of the result of the discussion, and forwarding him a copy of the Committee's report.
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ROSS CREEK RESERVOIR., Evening Star, Issue 7944, 27 June 1889
ROSS CREEK RESERVOIR. Evening Star, Issue 7944, 27 June 1889
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