BIG WATER SCHEME.

Waikato Times, Volume 107, Issue 17975, 21 March 1930, Page 9

BIG WATER SCHEME.

MAGNITUDE OE TASK. WORK PROGRESSING WELL. SHAPING PUMPING STATION. No complete idea of the magnitude of Hamilton’s waterworks scheme can be obtained without a visit to the site of operations. A considerable amount of work in connection with the big £40,000 job has already been completed, and the recent fine weather has especially favoured the contractors for the new pumping station and reservoir. The average citizen knows that a fortune is being spent on permanent improvements to the town supply, but, he has only a vague conception of the immensity of the plant which will ensure this ideal. The first definite stage towards completion will he reached in two or three months when the new filtration plant and pumping apparatus •will come into use for the first time. Better water will immediately he noticeable, hut the pressure in most areas will not be appreciably improved until the new reservoir is filled for distribution to the town. The borough engineer, Mr R. Worley, is hopeful that this red-letter event will be recorded by about Christmas lime. Owing to the wet summer the demand for water has not been abnormal and the Council and contractors are taking their lime with the big job. Double the Capacity. The most dominant feature of the whole scheme, of course, is the far; that the town water supply will have double the capacity with practically m: increase in the cost per 1000 gallons The present six filters on the reservoir site in Ruakiwi Street are only capable of handling- 48,000 gallons an hour whereas the peak load (between 7 and 9 a.m.) requires 85,000 gallons. Thus it can be seen how existing filters are overtaxed. men all 12 filters are operating, the six new and the six old ones, the capacity will be 106,000 gallons an hour. How the Water Travels. Workmen are now engaged in constructing the pumping station which is situated near the present station. The pumps and other machinery, arc on the water and should arrive from England shortly. The long journey to be taken by ihe water from the river 10 the dinner-table is an interesting process. After entering the intake pipes the water passes through a screen chamber, which acts as a strainer to remove floating matter, and then into the pumping station. Lowlift pumps send the water to the sedimentation basins, where is remains in suspension for four hours before flowing down hill to the filters. On leaving the filters it returns to the pumping station and is pumped with highlift pumps to the reservoir and then distributed to the town. The advantage of this system over that now in existence is considerable. The present plant takes up the water from the river straight to the reservoir, resulting in the latter containing unaltered water and requiring regular emptying and cleaning. The complete filtration plant will be able to cope with the peak demand which, as previously stated, is more than double the average demand. The existing pumping plant possesses two units each capable of pumping 650,000 gallons daily and one unit which will pump 1,000,000 gallons daily. The new installation will have three units of 1,250,000 gallons a day each. Provision will he made f-or the future installation of two more- units of equal capacity at extremely low cost when the demand for water justifies it. Present Plant to Go. It is the intention of the Council to dispose of the present pumping outfit, which will be useless and was never constructed to deal with pumice and silt-laden water created as a result of Ihe Arapuni erosion. This content in the water involves a tremendous amount of wear and tear on machinery constructed l'or clear-water purposes. The first glimpse of the concrete sedimentation basins on the terrace above the pumping station obtained by a layman would probably cause him to exclaim: “How ideal for municipal baths!” The flow into -these basins is regulated so that no matter what the river level may he, just the right quantity of water will occupy them to ensure adequate settling of extraneous and foreign substitutes. To enhance the effect of the static condition of the water the latter is treated with sulphate of alumina before entering the basins, thus causing matter in suspension to settle more readily. Each tank will hold 212,000 gallons of water which is four times the hourly pumping capacity of each pump. Making Use of Nature. The construction of the sedimentation basins on the terrace is only one instance of how the borough engineer has utilised natural resources for the sake of labour-saving and economy. On the reservoir site huge steel plates, girdenrs and other equipment are ready for a start to be made, on ! Hamilton’s future landmark. When I Ihc reservoir rears its lofty head over j Ihe town and all connections with the I other units have been made, the wis- ! dom of councillors and ratepayers and I lie ability of the borough engineer will tie consummated by the pressing of a switch and the town's water problems will be no more.