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the order of £4,000 for nine months would be required to cover salaries, allowances, labour, transport, etc. It would be reasonable to apply for assistance from the Colonial Development and Welfare Fund in meeting the cost of this Survey should such assistance be considered necessary.
Water Supply.
The particular aspects of water supply to which my attontion was called wore those relating to underground water resources, rural water supplies, and the Tai Lam Chung Dam Scheme.
The question has been raised as to whether the Tai Lam Chung Dam Scheme, estimated to cost $64,000,000 to $96,000,000 and to take seven to twelve years to completo, could be roplaced by an underground water scheme on the Island or on the mainland, or both.
Since this schemo is expected to provide Hong Kong with an additional supply of about 20,000,000 gallons of wator per day, there is in my opinion no prospect whatever of so large an amount of water being obtained from ground-water sources, and I seo no prospect of obtaining the required supply except by means of a surface scheme such as that of Tai Lam Chung.
The Island is built up very largely of granite, which normally yields very small ground-water supplies.
It will be recalled that the bunnols driven into this rock at Hong Kong and Kowloon in recent years yielded only a little water of negligible importance in relation to the town's demands.
On the mainland the rocks comprise various igneous rocks and some ancient scdiments, which are normally capable of yielding supplies adoquato for rural use or for small townships, but are of negligible importance from the point of view of supplying a town with the population of Hong Kong.
I discussed with the officers concerned the question of rural water supplies on the mainland. The problem is not yet clearly defined, since it depends largely on the unknown factor of the rate of increase of population in the near future.
It appears,