THE WATER SUPPLY QUES TION.

Otago Daily Times, Issue 7542, 20 April 1886, Page 3

THE WATER SUPPLY QUES TION.

At last night's meeting of the City Council the following report was received from the city engineer and referred to the Water Supply Committee. The Council will probably procure one of the waste-water meters before long and give it a fair trial. The cost of the meters is about £60, and in all probability about a dozen ottbeni would be required for the city of Dunedin Extra inspectors would also be required but it is thought that the saving effected would 111 a very short space of time amply compensate tor the extra expense incurred. Mr Mirams' report is as follows :

triTv??p£ ? Ce» lth y°»r instructions, I proceeded to Lyttelton tor the purpose of inspecting the work?&i 1 a D,? ac°lls waste-water meter which has Ooimcil, and beg to report as follows:— The niglit inspection took place on the sth inst. ami the working of the meter was shown very clearly by the various methods adopted of shutting lit n f valves were closed, which prevented any nZ.il L Wi tfV r thro"Sll «'c meter, the recording oenc irK! lH Zer°> T'\ W, he" thesew«re opened thl pencil instantly marked the change and the rate of ""' rec? r(lll 'g diagram. The rate of (low was varied by opening and shutting adjacent house-ser-vice taps opening the valve into upper level supply nl),h- *, t V '°7 down the street channel. Under nil these tests the sensitiveness of the instrument ™s satisfactorily manifested, and the water being P^r^r(SroO^e lzero eirj illg "" ""***' mwn- fcl!V" gllt iK\ ha ins I'liCti(»i t»e consumption at midrng if, was at the rate of lOOOgal per hour. On tho tollowing night it was reduced to 800«aI per hour, increasing up to 6 a.m. to 950ga1 pc? hour. This was above the ordinary average, as explained to me by the inspector, and the causes would have to be discovered; the average nightly consumption betore the meter was in use being 500 K al per hour and "reduced to 250 gal per hour by the use of the meter. 11ns latter quantity is known to result chief! v from urinals in various places. J The total domestic consumption in Lyttelton does not exceed 50,000 gal per day, so that trie quantities we were dealing with were very small. By opening only one fin tap the. consumption showed an increase of 700gul per hour, so that the above waste r

misuse of OJOgal per hour musf, have resulted from a lew cases at most. The operation of the meter depends upon the velocity of Hie water in the main on which-the meter is placed. When the water is at rest ami no consumption! taking place, the pencil stands at the zero line on a prepared and ruled diagram. This diagram is fixed on a revolving frame moved by clockwork, and completes a revolution in ■>.( hours. Any water drawn from the main pipe produces velocity,.and the pressure in the main being thereby reduced, the pencil drops, marking a vertical line on the diagram and showing ay the depth it has fallen the rate in gallons ncr hour Unit the water is being drawn off. If no ■MWihor.al or less quantity were drawn off, the pencil would now mark a horizontal liuenlongthe diagram aim continue that line for the 2-t hours' test, when the diagram would be removed and another substituted. In practice, however, the flow in the main vanes, and consequently the velocity of the water and the pencil rises or falls accordingly The variations durinst the night are very small compared "icii those during the day. and any change of now continues tor a longer period at that rate, mnkina the horizontal lines mores distinct, and enabling the inspector to determine the waste and to locate it after one or more trials. I am informed that the results in Lyttelton have been very satisfactory, not only in detecting but in waste, as the consumers are well aware ennt the inspector has the matter so much under a,l they ar® more Rarefl'l than formerly. Alter the inspection which I have made, I am confirmed in the opinion expressed in my report to the Water Supply Committee of 16th March last Chat a very large saving could be effected in Dunediu by the use of this waste-detecting meter. I would respectfully recommend the Council to rixone or .two meters in selected districts within the city, and I have every confidence that the same uenelicial results will follow here as have been e"peneneed elsewhere. The cost of the meters delivered and fixed will be about £70 eacli; so that the experiment would not be costly, and would determine the question "of their extended use. From I'J to In meters would be required to command the £1500 at an expenclitm'e ot trom £1000 to SUPPLY OF WATER FOR MOTIVE POWER.-OAMARU. dirVn^V i" J°urney I st°PP«l at Oamaru, as ?vi?p ' t Ol'- ler fco milko iQ(JIIi'-es respecting the flater motors, in use at that place. None of the the Z?T ',"* W°rk ? nrin S m-V v^it, as a burst in the lace had occurred a few days previously and some further time would elapse before if was repaired; consequently all the motors were stopped for at least, a fortnight, as the quantity of waterin the reservoir was not sufficient for the domestic wSr^uj^^t'^&^'ss rating Company. The theoretical horse po ? er supplied-to each motor varies, from i-horse to 29-horse. The Refrigerating Company is supposed to be supplied with 50-horse power■effective, but In tins case there is a question as to thequanitv of water used by them and the power obtained " , in ordinary cases the water delivered is calculated S«,m c! 1-i'" d, tl'c consumer is required to lay a uotm n Jlar^ toensnre "'at pressure at the le ed af Oo' lseqileiltly.,"« gallons^per hour de meied at a pressure of 751b represents one-horse power theoretical. The charges made by tie Git Co ic,l are based upon the theoretical horse-power rates:- i." accordance with the following Theoretical For 12 hours per For 24 hours Horse-power. dayand under. per day I h.p. and under £5 per annum >- Over i-h.p. to i

h-P-Over A Ij.p. to 1

£T 10s per annum

Overl h.p.to 4

£1210s per annum

ii p"'.i ••• £1210s per annum Above4h.p. ... £10 per annum £1210s per arm. Motors of 4-h.p. and under are not allowed to work more than 12 Hours per day. sive of tW °IIEl 1EV rp' th f erefore, for a motor (excluU^aifofeooSeSo^p^ highest charge is for a small motor of f-h £' t c :«taihted h ™be'?f l ab°"* W Per ttouiaid^ii^ thei mnrS- 12-botlr8> daily use of the water for Mie sum of £o per annum. mw V 5 ne? igerlt-in,g ComPanyhave a special agreement under which they pay JEIO - per annum ncr "tfT f°r **J»»™-™> of tl/e water; conTeIq o vpr J t y?u b + f ng sllPPlieu with Hie water at a ihoukndgaC""" oUe" third °f a P6n"y The total revenue derived from the 22 motors representing 115-horse power theoretical, is £1356 £ per annum, wliich, with £500 per anuum from thl I ,.J?? l;y7 eporli t0 the w'iter Supply Committee of Ifath September 18841 pointed out that the average cost of supplying wafer within the city of Dunedin wasifi-lOdperlOOOgal.so that it is at once apparent that water could not be supolied in Dunedin for SSI~' 6 P^ Ver ? b- the Oam'"-« Prices, the lowest charge with us being 6d per lOOOgal. The conditions in Oamaru differ from ours. Their water supply is at . tlle preS ent time far beyond the tow!' 8 !? t f"?/ h nT filOtnri! lg --^"irementTor « dZo'se of ar M6y laVe f a large s»rPl»s of water to Slnwr.tt ■ T ve! C rat, es' an'l it is offered at CJicse lowrates in order to induce consumers to take ™"ir rnTT n* a"d 18"in mains from th^ reservoir to the town have been estimated bvthe borough S!E t n" Pply f: 5-.°- horse powei' tl'eoretieal In uo es ThPfn I<? Cl"a, nti ty v, required for domestic pnrb?m filu nnn C°m' °/ the work- I am informed, has been £I*l,ooo, so that a revenue of about £11 000 per inaeZenstinn W* pay intent andTo?king expenses to make the necessary annual extenßinns coS'nefesf 0-"066' *°- ~S "if wllole of the estimated .150-horse power utilised, the revenue from same should be about £0000 per annum, which, added to the water rates and other sources of income, would make the total flWfll^ £f 3o° Pel" aulmm- le^ng the deficiency to be made up by an increase of 40 or 50 cer cent, on the present charges for motive power. P me increased consumption of water would thpn probably necessitate an enlargement oP he wnte" th^eser^-f t0 brin« the re^lisite Quantity into

W^iMd X ! uPply-i b?i, n& dnwn from the river W.iifcaki, the wateravailable is practically unlimited and the scheme offers peculiar facilities for the use 7nZT? ne?' ibr 00Uld ? Ot' l think' besafd hat the Snh r7!H er for f machlnery was a self-supporting blanch of the waterworks scheme, requiring no assistance from the rates or other sources of revenue