HUTT PROBLEMS.

Evening Post, Volume LXXX, Issue 133, 2 December 1910, Page 2

HUTT PROBLEMS.

WATER SUPPLY LESS THAN WAS THOUGHT. TROUBLE AT THE SEPTIC TANK. REPORT BY BOROUGH ENGINEER. PROPOSED ALTERATIONS. Two matters of great importance are at present engaging the attention of the Lower Hutfc Borough Council. They concern the capacity of the water supply, and the working of the automatic hydraulic pumping apparatus attached to the septic tanks. As regards the former, one of the main features of the trouble is — a Port reporter was informed — that the council has in the past been, labouring under the erroneous impression that there was a much larger supply of water at command than is now found on investigation to be actually the case. The council believed that there were a million gallons a day — one shift of eight hours is worked each week day — whereas ta obtain this quantity the full twenty-foul hours would have to be worked each day. This would mean running three shifts each day, involving a great deal of extra expense and heavy wear and tear of the machinery. SHORT OF ESTIMATED CAPACITY. But even supposing the pumps were kept working continuously all day, they would (it was stated) nave to pump 1 at the "rate of 750 gallons per minute to produce that quantity with which they had been accredited ; but at present only 400 gallons are running from the wells, and, this being so, a full twenty-four hours' operating would bring forth not 1,000,000 gallons as had been stated to previous councils, but half that quantity. The borough engineer (Mr. W. .J. Rdche) told a Post reporter that he had been experimenting with a view of - pumping directly off the wells. So far as he could see, it would be possible to introduce this system and work at 750 gallons per minute for eight hours daily. This would obtain a much quicker flow than was now possible. At present the reservoir was in the position of being only, able to gain on the average lft per day — clearly not enough to hold for emergency. He was proposing to pump direct from the wells, thus pumping at the quick speed of the engines, which were at present running on the slow speed. In this way nearly twice as much water would be obtained than at present. A DEFECT IN CONSTRUCTION. Dealing further with the- subject in a report to the council, the engineer states that on his initial visit to the pumping station, the first thing attracting his attention was the very small interval between the tube wells, which, in his opinion, had been sunk too close togethei, so that they would probably interfere with one another in action. The stratum in which the wells terminated j appeared to be fairly open, but that the i wells were drawing from one another was. he says, only too evident. Of a number of experiments (detailed), all of which pointed more or less to the same conclusion, the first bore out his contention. Testing the flow of one well, he found that there was a diminution of 20 per- cent, in its output when the other wells were being simultaneously drawn off. Indications pointed to the fact that the stratum from which the water flowed was not homogeneous. In testing the combined delivery of all the wells, it was found that the inlet chamber of all the wells could easily be pumped dry by putting on the quick specd — in itself a- rather significant statement, comments the engineer. HAS THE SUPPLY DIMINISHED? Mr. Roche gives some interesting data in regard to the question of whether the supply has fallen off. He says r— "Whether the yield of the wells has actually diminished I cannot say, but Mr. Ingram, who has been in charge of the pumps from the beginning, has told me that' at the very first trial with the quick speed, it was found that the water was exhausted in a very short time. The capacity of the pumps on the quick speed is 750 gallons per minute, so that if the wells yielded 1000 or 800 gallons per minute when they were first sunk, they very quickly declined to their present yield, but have remained fairly constant since then." Continuing, the engineer says that if the yield was not increased by putting direct suction on the wells, as was proposed, then it would be necessary to put down extra wells. TOO SMALL A MARGAIN TO WORK ON. The engineer also stresses the fact that in his opinion the present margin of water held in. Teserve is too narrow, unless the council is prepared to work longer hours or double shifts in the not, distant future. This can only be carried out at a very heavy expense. As an instance of the importance of his contention he points out, that owing to a burst in one of the mains, a loss of 40,000 gallons of , water occurred. Had this taken place in conjunction with a breakdown ,(some of which had been experienced) of the engine-house plant, a temporary water famine might possibly have ensued. In recommending that the engines and pumps (as well as the engine and gas producers, as was already the case) be made interchangeable, Mr. Roche states that as things obtained al the/ present time he was faced with the possible coutiiigency that if the "A" engine should happen to break down and the "B" pump faU, the whole of the pumping machinery would be brought to a standstill. HYDRAULIC LIFTS. ALMOST PARALYSED. The other matter which, is at present causing the council and the engineer no small amount of concern is the unsatisfactory working of the hydraulic lifts attached to the Alicetown septic tank. Referring to the subject, the engineer- states that one of the consequences of the heavy rain that fell on Thursday, ,27th October, was a considerable leakage into the sewers, with the result that the machinery at the Alicetown pumping station was almost paralysed. This state of affairs ' was brought about by a combination of causes, ail of which were adverse. After outlining these. Mr. Roche states the outfall could be improved, either by giving more fall — out of question under the circumstances — or by putting in a longer pipe. MATERIAL ALTERATIONS REQUIRED. Other directions in which material attention to the septic tank gear are imperative are reported upon. The efficiency of the hydraulic pumps is at present greatly diminished through the exhaust water being delivered into the outfall pipe. A further cause of the failure of the pumps, and one which would in time completely destroy the hydraulics, is the use of strainers on the suction pipes which he found • were being- employed. In his opinion, very little straining of sewage matter was necessary. He considered that the chamber should be remodelled. A SERIOUS CONTINGENCY. Summing up, he leeommendetl that the council would be well advised to . put the whble matter of fixing and '• "tuning, ug/i and the. getting of the

pumps into proper running order, into the hands of Messrs. Richardson, Blair, and M'Cabe — agents for Messrs. Glenfield and Kennedy (makers of the plant). In emphasising that the position was at present a serious one, Mr. Roche remarks that "if the kind of things (outlined in full) is likely to happen when the eastern septic tank is connected, we shall not be able to work the two hydraulics alone." In an explanatory note Mr. Roche states that defects exist, some of which can be easily altered, but others will require very careful consideration, and further and more exhaustive investigation, before he would feel himself in a position to suggest efficient remedies, with due regard to economy.