CO129-543-10 Water supply- Shing Mun Valley water works 21-4-1933 - 8-2-1934 — Page 25

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sufficiently advanced for an examination by our senior

partner

Mr. Binnie early in November.

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Generally, the design - skeleton drawings of

which have been sent by Air Mail to Mr. Hull - embodies

a watertight concrete cut-off wall carried into the

solid rock which will be grouted as may be required.

Above ground the waterface will consist of a reinforced

concrete slab wall inclined at 1 horizontal to 3.4

vertical, resting against a concrete retaining wall,

which, in itself, will be supported by a rock embankment

on the downstream side formed of large "plums" and

crushed stone to give a pervious but adequate support to

the concrete retaining wall.

The foundations of the retaining wall and rock

embankment will not require to be founded on sound rock

as is the case with the cut-off wall, and the design is

so arranged that the concrete retaining wall and rock-fill

embankment are free to settle independently of the

reinforced concrete slab wall.

The site for the dam is some 200 feet

downstream of the large waterfall, and some 400 to 500

feet downstream of the various possible sites considered

above the waterfall. The selected site involves an

additional height of 50 feet as compared with a site above

the waterfall or some 275 feet above stream bed, but it is

definitely the most suitable having regard to foundation

conditions.

We have taken out an estimate of the cost, and

have no reason to anticipate that it will exceed our

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