WAIMATE WATERWORKS

Timaru Herald, Volume XC, Issue 13265, 20 April 1907, Page 6

WAIMATE WATERWORKS

DETAILS OF INSTALLATION.

The {water for the supply of tha town » taken from the gorge of tha Waimate creek. ' Across this creek (at the site originally selected by the- engineer as being tha most -suitable for the reason stated in Ms report on the scheme) a" dam has been erected, ths length being 120 feet. In thd centre there is an overflow sill 25 feet wide, the height of tha dam on each *ide being two feet three inches above .the sill. The area of this waterway is sufficient to allow 6,000,000* gallons per hour to pass over when the creek is in flood. The top of the s-ill being six feet above the concrete foundation and bed. of the creek, an eighteen inch Penstock is built into the dam to draw of? the water at any time if necessary. The whole of the work in connection with the dam is built in reinforced concrete. Two rose pieces are also built into the dam, throe feet below the top of the sill through which the water passes before entering the main pipe leading to the reservoir. From the dam to the re?f.rvoir the distance is 169 chains. The pipe-laying over the first 45 chains is principally through broken country involving soms Jeep terrace cuttings, the mean hydraulic gradient over this portion being lin 372. For the remaining 124 chains the water is conveyed through a six inch, diameter cast iron pipe carried along the side of the main road to the reservoir, the- mean hydraulic gradient over this portion being lin 35. The water falling into the reservoir is regulated by an equilibrium valve, which only allows the Sow of water to rise to a fixed point, thus doing away with the necessity of an overflow; consequently no more water can be drawu front the intake than that actually required for town supply.

The reservoir has bien constructed close to the main road on (the terrace at Hayes creek, partly in excavation, and partly above ground surface, tho latter being seven feet above thejevel of the adjoining ground. The structure is circular and has a diameter of 100 feet, the height of the wail from the floor being fourteen feet, and the capacity being 686,000 gallons. The concrete floor (7850 sqr. feet) is laid on a bottom of compact clay and shingle formation; has a slops of six inche* from the wall to a sranph in the centre, from whence a 6 inch pipe is carried underneath the floor for the purpose of cleaning out. The whole of this work has been carried out in reinforced concrete, tight inches in thickness. Thj town supply from the reservoir passe-* through an automatic float outlet- taking in the water 18 inches below the surface, insuring to consumers a pure and aerated water. A by-pass is also provided for maintaining the town supply during any time the reservoir is being" cleaned out. From the reservoir to the town the water runs through a six inch castiron pipe along the side of -the county road, crossing Hayes and the Waimate creeks, a AiZ tance of two miles ten chains. The pipe in crossing the creeks is laid at suth a depth in the bed as to prevent any possibility of ,?. washout during a flood. Town reticnlation.—The total length of castiron pipes laid within the Borough is 10 miles 55 chains of the following dimensions:—ls chains of 6 inch. 4 25 chains of 4 inch. 6 miles 15 chains of 5 inch; nothing less than three inch diameter pipes being allowed. There 188 ball hydrants. 56 sluice valves. 5 concussion valves, and tv'r valves where required. The hou*e service connections with th<» water mains to section bopndnries number about 400. The daily supply of water' which bs hro"«'ht s"*" town and which the main pipe is capable of carrying is 540.CG0 gallons, sufficien'to supply 40 gallons per head pjr d«y for a population of 13.500 Fixfire prevention purpose-' a splendid j,r:<sure is. obtainable, ranging from 7QU>« on th": square inch at the north wot boundary or highest part of the boroujrh to 941bs in Queen or principal street, to 1191bs r.n the square inch at the end of lower High s'reet. or lowest part of the town. The whole r.{ the work has been carried out in. a thoroughly satisfactory T"nnnf r and reflects credit on the engineer (Mr James Crawford) and all connected ■"-•(■J, Th. V»?~" \. 0t,,1 T. Tim-t. r.f Dunedin supplied all the pipes and fit-t-

ings; the contract for pipe laying and plumbing work was in the hands of Mr C. Hodg«s. (Dunedin), and having an efficient staff of mechanics and labourers the work was pushed forward and the last of the pipes laid within contract time (five months) which speaks well for the expeditious and thorough manner in which ths contract has been carried out. Mr G. G. Ross was clerk of works. The building of reservoir and dam at intake was under the supervision of Mr J. A. Day, ' the work giving satisfaction. , BO—M—BM