50.
51.
52.
53.
54.
C/A
-12-
utmost development of the high level sources.
The total
direct and indirect catchment area of the gravitation portion of Mr. Henderson's scheme amounts to some 6,150 acres: the
scheme we recommend has a corresponding figure of 9,000 acres
with a possibility of bringing in a further 1,300 acres.
As the necessity arises, a catchwater running along
the southerly flank of the Tai Mo Shan Range at a level of
about 700 above datum, could be constructed to deliver water
into the Shing Mun Reservoir at Pineapple Pass.
This catchwater would drain some 2,800 acres and
add about 4 M.G.D. to the yield of the scheme.
A subsequent development would be to lead into the
reservoir by catchwater the run-off from some 60 acres lying above the 700 contour and to the east of the reservoir, with
the consequent addition of about 1 M.G.D.
The penultimate development would be to run a
catchwater along the northern flank of the Tai No Shan and
also the northern and eastern slopes of Grassy and Needle Hills, which form the north-easterly boundary of the reservoir basin, at a level of 1,000, and to bring this into the
reservoir basin by a tunnel under Lead Mine Pass at a level of 650 feet. This catchwater would drain about 2,700 acres and add about 31 M.G.D. to the yield of the reservoir.
We have recommended the tunnel under Lead Mine Pass
to be driven to a mean level of 670, so that if still further
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