OUR WATER SUPPLY.

Evening Star, Issue 14628, 26 July 1911, Page 2

OUR WATER SUPPLY.

TO THE EDITOR. Sir.—Your leading article on this subject in your issue of the 17th inst. is a very timely reminder for our civic authorities that something definite should be done without delay in the conservation of the rain that falls on our watersheds by means of storage reservoirs before another possibly hot and dry summer comes upon us and places us again on the very brink of a water famine. Happily, whilst w© were all dreading the continuance of the drought some months ago, the rain came just in time to prevent the direst consequences to the whole community. Nevertheless, wo had a very narrow escape. As you say, certainly the question ought to be faced and dealt with without delay.” Your suggestion that if the Silver-stream race were properly attended to, and piped wherever necessarv, a much improved supply might be obtained from that source, is no doubt the fact. Much water has, I understand, been lost in consequence of leakage through faulty places in the race. All this should be obviated as soon as possible, and then we shall get a better supply from that source without any serious extra cost. Then there is the Waitati-Leith watershed. I think it was Cr Marlow who said, in his address prior to his recent reelection, that there was enough rainfall m that district to supply all Dunedin for many years to come if it were properly conserved in storage reservoirs to be made in the district. The residents in the lower Leith Valley and in Woodhaugh have protested against the construction of such a reservoir at the head of the valley, on the ground that the land there is not sound enough, and that if the dam broke the water would carry destruction ail down Woodhaugh and across the north end of Dunedin. That is probably true, and it appears that the Government have consequently disapproved of a reservoir being constructed on the proposed site. But, as was pointed out some time ago, and possibly as may be known to the Water Com-; mittee, there are other sites in the Leith Valley to which there oould be no valid objection, as they are out of the direct line down the valley, and therefore, even if the reservoirs were to burst, the force of the water would be broken and greatly lessened, in consequence of its being discharged amongst the hills opposite before It found its way down-the valley. There are two fine sites for storage reservoirs just above M'Craw’s, where hundreds of millions of gallons might be stored at a very small cost, judging from the natural conformation oJ the ground, and with the utmosi safety A stone might be thrown frojr one lo the other, and the two reservom would then be easily supervised by on, man and water stored there would be at £ height sufficient to supply by gravitatioi all parts of Dunedin, even if not Roslyi and Moroington, which are already pro The objection raised as to the ground ai the head of the Leith Stream not beinj sound enough, for safety, is not the onb one. The watershed is there far td< limited for a large supply of water beinj

obtained, as it is far too high up th'i J valley, aod consequently large quantitie;

of rain falling on some of the land acquired by the City Corporation could not be led into a reservoir so situated, as'it would be up-hill. This would not apply to th'j sites lower down, as it would be easv to lead the water by race or pipes to sucli sites all through the land bought by the Corporation for this very purpose at a very considerable cost. Presumably a goo'd deal of this land will have to .be resold unless it can be satisfactorily used as a watershed. At present the rain falling on it appears to run to waste down the hillsides into the Leith Stream. The water from the Leith-Waitati district is of a very good quality, far better than that from the Silverstream, and millions of gallons are daily running to waste for want of storage reservoirs. In short, we have a fine watershed, but do not make proper use of it. I see it is now proposed to obtain from Parliament power to bring in water from the Lee Stream. This may possibly be a sensible project, but if carried out it would cost a very large sum of money—probably more than £loo,ooo—before it was completed." Then, again, there would be serious delay in carrying the project out. In view of our greatly increased responsibility involved in our undertaking to supEly Green Island, Anderson Bay, Kavensourne, and the North-east Valley, can we afford to run the risk of further dry summers and a possible water famine until this more ambitious project is carried out? And, besides, we have probably quite enough debt in Dunedin to carry, even as matters now stand, without launching out into further very heavy expenditure. Let us make the best of what wo have for the next 25 years, and then, perhaps, we may be able to bring into Dunedin pure water from Lake Hawea! Who knows?— I am, etc., Aqua. July 25.