Taihape's Water Possibilities.

Taihape Daily Times, Volume XI, Issue 3347, 27 November 1919, Page 6

Taihape's Water Possibilities.

I . EXPERT’S PRELIMINARY . REPORT. ‘ (Continued from last issue.) GRAVITATION SCHEME. - T I inspected the Hautapu river with a View to gravitation scheme. At 3 point beyond Mataroa. railway station the river is 340 feet above the streeat level at orpabout the Town Hall, and about 4'o chains above the high level reservoir. The length of a main to bring water from the point to the town would‘ be'a-bout eight miles if Ul9 Mataroa tunnel was used. The intake site inspected is, I understand, from levels given by the District Engineer of Railways, -about 15 feet above the tunnel level and distance to the tunnel about two miles. If an ultimate sup-, ply of 400,000 gallons per day was de- l cided ‘upon (‘and such supply should‘ be suitable for 10,000 peopde with proper care) a 12 inch pipe would oe required to reach the tunnel level from the site inspected. This, how.ever, is not an imperative necessity, because further ‘head can be obtained by going up stream about another half mile. A 9 inch diameter main from the tunnel onwards would bring. in 200,000 gallons per day to the ex~ ‘isting high level reservoir, and would! also deliver another 200,000 gallons tog the ‘low level service tank before: ‘mentioned. The cost: of this gravita—l tation main can only be roughly approximated. If the distance is correct. and the tunnel is used, the cost of the pipes laid in place would be about £20,000. A sum of £IOOO should be allowed for head works, and ’£10»00I as an allowance for use of tunnel and ‘the'_Worl< being done by the Railway Department, making a total cost to {the reservoir of about £22,000. ‘This ‘price is based on using steel pipes, and, can only be considered as a rough’ 7:e’s-tiniate. For the purposes of a preflliniinary consideration, I should adiviseyour Council to allow as follows: estimate £22,000; Engineering, expenses, etc. £2200; First’ capital charges 6%: per cent. £1573; Total £25,773. Allow £26,—! For. the next few years 200,000 l gallons per day would ‘be ample forl the whole "of your expected population, therefore the water could be turned jintoithe high level reservoir, an'd_thc low level service tank need not be! considered until your ‘population’ rached 4000. In order to complete your; reticulation the previously men- I tioned £BOOO plus contingencies, expenses etc., and first year’s interest or say ‘£9400 should be added, making ' the total 'cost»of a gravitation scheme and a complete 'reticulation about £35,000 to £36,000. Before you can : submit the proposal to your ratepayers ' .much closer investigation will have 0 be made. The capital charges of! the loan, for the main and heads ,1

Worke costing £26,001) at 6%, per cent.' Lnclusivc, would amount to £I7OO per year. You Will"therefore see that it will -be cheaper to pump provided the suction gas plant is not called upon axcept during drought seasons. ‘ CLARKE’S SPRING. _ Mr Clarke, Water diviner, has reported to you that d a large underground flow of water exists on Mr Nathan's property Section No. 13. The peg pointed out to me is about 190 feet above the Town Hall. Mr Clarke states that water in large quantities will -be found from 150 to 200 feet below the peg’. If 200 feet is taken, then the water leveliwill be 10 feet above the river level at the power house. I cannot discuss the probability of obtaining a large flow of water at the point indicated. This is a. mattter for practical test after geological advice

has been" obtained. Assuming that sufficient water is found at 200 feet level,’ this supply will save 100 feet pumping head. In a population or 3000 people the ‘saving in pumping will amount to 14 h.p. continfiously,

‘r 28 h.p. if the pumping is done in 2 hours If a value of £8 .pel“h.p. is laced on the,poWer used, it being sed- off the peak load, the annual savmg by having 100 feet less head 'to ift will ‘be £224. There will be can‘tal charges on land purchase, cost or ell. and maintenance of same‘. I

nderstand that the Council has been informed ‘that the purchase of land {vim cost £SOOO and that the Well may be expected to cost; £700." If this is so the annual capital charges alone at‘ 6%,’ per cent. incTusive will be £370 j)er_ year. Your Council cannot. therefore‘a.fford to pay the above mentioned price for land purchase. Even ifa. large volume of water is discovered at 200 feet below Mr Clarke’s peg, it may be unsuitable ‘for you: fpl‘ll-poses. Therefore until :11} :;g;.tLlal well has been sunk, "and the flow tegtcd by pumping and the water ex2mi_ned_»fefAso_ftnesg and purity, _I am a’i;_z:,"cAeml3lAe’c”"e3»' di‘s2«ldvzi“ntage,“ ag my w<leVic9..@*2n?;“v’£éllx‘ 5j;¢0¥“1°?1 fif 0913* ‘AM

based on concrete facts, which have been more closely examined and tcsted.] If the land can be purchased at much below the figure above mentioned, and if a well is sunk and suflicient ‘suitable water is found by actual continlued pirmping and other tests, the 'pro—j posalaxray be worth considering. I. ‘ CONCLUSIONS. From the preliminary investigationsl [made,vl have to advise your Council: ‘ 1.-—The existing turbines ‘should the tested for efficiency and average flow of _water examined. » 2.—lf the turbines efficiency is low at ‘ halt‘ load, and the average flow of the river say for six to nine months warrants it, a -smaller -turbine set from 25 to 30 K.W. capacity should be installed. ‘ 3.—A gravitation -scheme should be considered as costing about £26,‘ 000 for the Main and Headworks; and not including any reticulation. 4.——lf pumping is to be adhered to, "the pumping plant be reorganised and a low level service tank be erected. 6.—-I am of the opinion that any doshould be done to test the \Va“'ter Diviner’s statements, and, until these tests are made I can ofier no

opinion. 6.—1 am of th opinion that any development of power in the river for pumping purposes only his not wise-. It would be much sounder engineeering to develop more hydro electrical power at a, later date when your demand is greater, and in the meantime carry on with the occasional use of the suction gas plant. " 7.—1 am inclined to- the opinion that a reorganised pumping scheme with _-a low level service tank will be the cheapest until your population reached 4000, ‘but you will have irritating interruptions, ‘ anxiety and expense until 9. new high level pump is installed. The question of pumping cannot be fully deter-mined-until Nos. 1 and 2 are invcstigated as indicated.

At the time of my Visit I took notice of the position of the danlAl'e_lative to the road and bridge in the near vicinity, and came to the conclusion that it would be a difficult matter to raise the dam without seriously interfering with the bridge level. Since Writing this report 1.. have made inquiries, and learn that it may be possible to induce the County Counoil to alter the road and rebuild the bridge. If this is found to be‘ correct, I would alvise your Council to seriously consider raising the height of the dam, so as to secure a greater head and larger storage. I did not examine the design of the dam, but I feel with carefui Work, further "head should be attained. The design of existing dam, tunnel, pen stock and turbines would have to be reviewed. ‘As this question is hardly within the order of reference, except in an indirect manner, I do not feel justified in spending time in considering it in detail until advised by you. Yours faithfully, (Signed) H. F. TOOGOOD.