ASHBURTON WATER SUPPLY.

Press, Volume XLVIII, Issue 7863, 14 May 1891, Page 6

ASHBURTON WATER SUPPLY.

[FROM OUR CORRESPONDENT.]

Owing to the exceptionally light rainfall in the Ashburton district for the past three years a large number of the springs that originally flowed to the surface and gave a superabundance of beautifully clear water have become dry, while the subterranean streams in many instances have sunk fully ten and twelve feet below their normal level. One of the results is that the residents of the borough of Ashburton, who have been mainly dependent on the upper water bearing stratum for their pump supplies, have been put to very great inconvenience. A large number of the pipe wells have given out altogether, and residents have been using water from the side channels for general purposes, and trusting to the neighbor who had the nearest deep well for water for drinking. The wellsinkers have been reaping a harvest, as many of the pipes have been driven down with a view to reaching the second stratum, but the inconvenience which a largo number of the residents have been suffering has once more raised the question of a high pressure water supply for the town. There would be no engineering difficulties in the way, but such a scheme, carried out to a practical issue, would necessarily involve a expenditure of money, and mean a pretty heavy special tax on the ratepayers. Apart from this there is no doubt whatever that as soon as rain does come in any quantity the springs will quickly rise again. In any case there are those who are wise enough to see that a high pressure schenie means opening up a very large and expensive question, while it has been proved beyond a doubt that there is yet an abundant supply of excellent dr n'.cing water to be had by driving pipes a total depth of from 40ft to 60ft, and thus tapping the lower stratum. The Works Committee of the Borough Council were asked to report on the underground water supply, ana at the meeting of the Council on Monday they did so as follows:—

" The Works Committee have considered the question of the water supply in relation to the failure of the present pipe wells, and according to instructions we have made inquiries into the matter, but have not had time to deal with it exhaustively. The information, however, that we have obtained enable us to give a report as to the general facts, and it appears that the failure of the underground water supply is more local than is generally supposed. The greatest number of complaints as to the ordinary pipe wells failing proceed from the district north-east of the Wakanui road below the railway line, and north-east of Havelock street above the line. The portion of the borough westward still has a good supply, though a few of the pumps are dry. It must be understood that this failure refers to what may be called the upper water bearing stratum, the only one that up to the last few months has been tapped, and runs from about 10ft or 12ft to 30ft below the surface, according to the locality. This stratum has evidently been exhausted, or dried up in the north-eastern part of the town, as before described, but at the same time there has been proved to bo either one or two strata below this that are water bearing, and also what may be termed semi-artesian. Pipes have been driven in Peter street east, Aitken street east, and at the engine shed at the railway to depths of from forty-four feet to fifty feet, and fifty-seven feet bslow the surface of the ground, and in each oase the water has risen to about thirty feet from the surface. On the north-western side of the line, the only success of which we have heard in sinking below the upper stratum, has been near the corner of Cameron and Grigg streets, where the pipe well, dry at thirty-six feet below the surface, was sunk deeper, and now gives a good supply of water. Owing to the fact that that this lower water-bearing stratum has been so recently tapped, we cannot judge of its permanency or quantity, but we may conclude that there is considerable pressure from the fact that, in the few wells that have been driven, the water rises so many feet (from fifteen to twenty-five) above the bottom of the pipes. From the experience gained there seems to be little risk in sinking deeper in cases whore the upper stratum has given out, bxxt as we have found sufficient exceptions to prevent us saying with absolute certainty that a supply of water will be obtained at any particular depth, we purpose to continue our enquiries so as to obtain a more extended view of the question, and if the Council desires to present a fuller report at the next meeting. We may explain that we are endeavoring to utilise our information by reducing the height of water in the wells to the datum of high water mark, so that the average depth of water below the surface of the ground in any part of the town may be easily ascertained." Cγ Williamson, in moving the adoption of the report, said it would prove useful in dispelling a wide impression that the Ashburton water supply was becoming exhausted. There had not been time to go exhaustively into the question before bringing up the report, but sufficient information had been gathered to show that even in the driest part of the town there was plenty of water at a lower depth than most of the pipe wells had bo far been sunk. The drought too would not prove altogether an unmixed evil, as the scarcity of water would induce ratepayers to sink a little deeper with the object of getting the eemi-artesian supply referred to in the report. The report showed pretty conclusively that under their feet there was an abundant supply of good water, and besides this he had no doubt that as soon as they again had a plentiful rainfall the springs would rise again to their natural level. Cr. Bibd seconded the report, but was not so sanguine as Cr. Williamson about a eupply being obtained at a lower level. Cr. Paul endorsed all that Cr. Williamson had said, and thought the Works Committee deserved the thanks of the Council and the ratepayers for the information they had furnished in their report. The rainfall for the past three years had been exceptionally light, and he was confident that there would be again plenty of water in the pipe wells after the first twenty-four hours' heavy rain. The Mayor also felt that with the first heavy rainfall, and the subsequent melting of the snow on the hills, there would be a material increase in the present underground water supply.