Chung Reservoir. This was achieved by building a pumping station with a variable capacity between 3 and 32 million gallons per day with outlets so arranged that the water could either be delivered to the tunnel or via some 3,000 ft. of pipeline varying between 21" and 48" diameter up to the Tai Lam Chung catchwaters. This installation permitted regulated amounts of tanker water to be delivered to the tunnel with the surplus gravitating via the catchwaters to the Tai Lam Chung Reservoir. The determination of the required quantities of tanker water and reservoir draw-off was the responsibility of Salinity Control Officers specially recruited for that purpose.
10.34. There was also some concern whether the saline water would mix adequately in the reservoir or whether it would sink to the bottom and become an embarrassment later. Following model tests at the H.K. University, arrangements were made to lay an 18" pipe round the perimeter of the reservoir to enable the water to be injected at selected points to encourage mixing. Fortunately the quantity which had to be transferred to the reservoir was much less than expected, and only 114 m.g. of the Pearl River water had to be pumped into Tai Lam Chung. Sampling indicated no undue build-up of pockets of highly saline water and it was possible to avoid constructing the pipeline.
10.35. Apart from works at the Indus River described at para. 10.07, other works carried out in order to augment existing supplies included:
(i) the sinking of shallow wells near the Muk Wu Pumping Station which, as indicated previously, yielded a total of approximately 140 m.g.;
(ii) two pumping units purchased from the Army authorities were installed on the Shing Mun River below Sha Tin to pump the yield to the Beacon Hill catchwater and a similar installation pumped water from the Ham Tin stream on Lantau Island to the Pui O Pumping Station to supplement the Shek Pik Reservoir supply;
(iii) Arrangements were also made with the New Territories Administration whereby crop compensation was paid to the farmers on South Lantau and all over-passes on catchwaters E & F of the Shek Pik Scheme were closed from November 1963 to April 1964 to enable the entire dry weather flow to be discharged into the Shek Pik Reservoir;
(iv) A pumping unit was loaned by the Fire Services Department and installed at Tsuen Wan filters which enabled the wash water to be pumped back to the Shing Mun Reservoir conduit for reuse.
NEW CONSTRUCTION
Conduit Road Service Reservoir
10.36. Site formation was completed in the previous year and construction of the 1.5 m.g. reinforced-concrete service reservoir was begun
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