still in excess of the available resources, and investigations were begun for a new source of supply in Tai Lam Chung Valley on the mainland. This work, consisting of extensive drilling and a geophysical survery was completed during the year, and it is hoped that it will be possible to make an early start on this new scheme which will approximately double the Colony's water resources within the next ten years.
Slightly over 40% of the Island's consumption is supplied from the mainland reservoirs, the water being conveyed across the harbour in two 21" diameter submarine pipes. On account of the hilly nature of the Island a big proportion of the water has to be pumped and in some areas re-pumped, necessitating a large number of pumps and service reservoirs. Most of the water sup- plied is both filtered and sterilised by chemical treatment and a satisfactory standard of purity is maintained, but sterilising of the filtered water has suffered somewhat owing to the failure of supplies of Chlorine Gas which necessitated a reversion to the use of Chloride of Lime. All water is supplied to consumers through meters, and the charge is based on the total cost of provision in- cluding capital charges. Severe restrictions in the hours of supply were imposed between January and June to make the available storage last out until the summer rains, and daily consumption reached record figures both on the island and mainland during August. The average daily consumption for the year was over 30 million gallons, while peak consumption was over 40 million gallons.
Delivery of piping ordered was still slow throughout the year, but good progress was nevertheless made with the relaying and extension of water mains both for the city and for outlying villages. All pre-war ground and pedestal hydrants have now been repaired, and the replacement of the ground hydrants by pedestal ones was continued. It has not yet been possible to operate the waste detection system, although good progress has been made with the replacement or repair of the waste detection meters. improvement in the delivery of water meters and spares has enabled the replacement of defective meters to be speeded up, and during the year most of the services were fitted with meters in good working order. At the end of March about 25,000 meters were in use. A new meter repair workshop for the Island was completed.
An
The erection of the new 8 million gallons per day rapid gravity Filtration plant at Stubbs Road was begun during the year and good progress was made. A new 400,000 gallon covered
concrete Service Reservoir was `constructed above West Point. Plans were prepared for new slow sand Filters at Wong Nei
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