Kowloon Reception Reservoir, Shek Lei Pui [1926- ]
This tunnel was part of the first section (phase) of the Shing Mun Valley Scheme. It is marked (I) on the map below.
Most of the water in the reservoir came from the Shing Mun Valley, delivered to the reservoir via the South Tunnel (H). The nearby Shek Pui Reservoir also feeds this reservoir, with a small additional amount of water coming from streams that run into the reservoir from the surrounding hills.
The reservoir was completed in 1926, as described in item 164.a of that year's PWD Annual Report:
(a) Reception Reservoir, Shek Lei Pui, for Shing Mun Water.—This work was referred to in paragraph 224 (f) of last year's Report.
Owing principally to labour troubles, the completion of these works was delayed, but by the close of the year the contract had been fulfilled and the dams satisfactorily tested.
In addition to the storage provided the reservoir is intended to regulate and to a certain extent clarify, the delivery through the Shing Mun Tunnels which discharges directly into it.
The following data is given for record purposes:—
Direct Drainage area 96 acres.
Top Water Level 480.00 A.O.D.
Volume available through draw-offs .. 38.15 Mill. Galls.
Additional volume available through
Wash-out 17.00 ,,
Area at Top Water Level 9 3/4 acres.
The works consist of: —
(1) A Draw-off Dam with Valve House.
(2) An Overflow Dam.
(3) An Overflow Channel.
(1) The Draw-off Dam has an overall length of 228 ft. and a maximum height of 48 ft. from the lowest foundation level to foot path level, which stands at 482.50 A.O.D.
The inner face of the dam up to 466.25 A.O.D. is of plain 4 1/2 to 1 cement concrete and above that level it is of ashlar masonry backed with 4 1/2 to 1 cement concrete. The hearting consists of 8 to 1 displacer cement concrete and the outer facing is of granite rubble in regular courses. The Valve Tower and House project from the inner face of the dam and are faced above 466.25 A.O.D. with granite ashlar. The draw-offs are designed to deal with the ultimate capacity of the Shing Mun Valley Scheme and are four in number each 18" in diameter. Two draw-offs are at 472.00 A.O.D. and two at 465.00 A.O.D. The Wash-out pipe, although situated outside the Valve Tower, is controlled from the Valve House.. It is of 18" diameter and its level is 450.00 A.O.D.
The following materials were used in the construction of the dam and Valve Tower:—
1,380 C. Yds. Fine Cement Concrete.
967 ,, 8 to 1 ,, ,,
111 ,, Lime concrete.
218 ,, Ashlar masonry
172 ,, Rubble ,,
(2) The Overflow Dam is situated at the eastern extremity of the reservoir and diverts the overflow into the Lai Chi Kok Valley about 1/2 mile below the Kowloon Reservoir.
The total length of the dam is 87 ft. and its maximum height from the lowest foundation level to cope level is 16 ft.; the overflow dimensions being 40' x 3'. The dam is faced on both sides with granite ashlar masonry, whilst the hearting is of 6 to 1 cement concrete.
An 18" draw-of pipe has been provided at a level of 474.00 A.O.D. in order that a direct supply to the Kowloon Filter Beds may be given. By this means the Kowloon Reservoir could also be charged with Shing Mun water should the necessity arise. Immediately below the overflow dam is a masonry gauge wall with a V Notch 2' 6" in height.
(3) The Overflow Channel commences at the Gauge Wall and has been continued down the hillside until a rock bottom was encountered. It is approximately 12 ft. wide by 4' 6" in depth and has a total length of 265 ft. The invert is of 8 to 1 cement concrete stepped to suit the slope. The side walls are of similar concrete and are surmounted by a granite ashlar coping.
By the end of the year the reservoir had been almost filled with water from the Shing Mun River and was found to be practically watertight.
1926 Estimates, ....$60,000.00 Total Est. $175,000.00
1926 Sup. Vote, 2,000.00
1926 Expenditure, ..$57,848.77 Total Exp. $157,120.41