CO129-459 - Individuals - 1919 — Page 271

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JAFFÉ ON HONG KONG WATERWORKS,

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into the lower reservoir. The dam (Fig. 9, Plate 1) is constructed of 6-to-1 cement concrete containing displacer stones, except the backing of the masonry of the water-face, which is of 4-to-1 cement concrete without displacers. It is faced throughout with granite masonry, The total quantity of concrete used in its con- struction was 24,520 cubic yards and of facing stone 59,930 cubic feet.

The length of the dam is 440 feet, and the height is 90 feet from stream-bed to crest-level, and 110 feet from the lowest part of the foundation to crest-level. An overflow crest, 100 feet in length, is provided. The thickness of the dam at stream-bed level is 65 feet, and at crest-level 5 feet. A valve-tower with 10-inch draw-off pipes connected with a 12-inch stand-pipe is provided. The con- struction of this dam presented no special difficulties.

CATCHWATERS.

The catchwaters for augmenting the drainage-area of Taitam Tuk reservoir have not yet been constructed, but surveys are being made for two of them. These two catchwaters will intercept the flow from about 1,107 additional acres; the construction of further catchwaters to intercept that from the remaining 1,493 acres will doubtless be proceeded with when necessary.

COST.

The cost of the first section of the Taitam Tuk works was $896,140. Taking the average pre-war rate of exchange which has been current in recent years as 28., this is equivalent to £89,614. The costs of the various parts of the work constituting the first section were :—

Intermediate dam

Pumping-station site and buildings

Pumping-machinery and erection

Roads, bridges, etc.

Pumping and supply-mains

Miscellaneous charges

Total amount

$

383,435

86,466

111,821

154,508

135,095

24,815

896,140

Papers.] LOW-LEVEL RESERVOIRS AND WORKS FOR PUMPING.

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equivalent to £241,756. The costs of the various parts of the work constituting the second section were :—

Taitam Tuk dam

Pumping-station, extension of buildings, etc. Pumping-machinery and erection (£24,700) and

Crown Agents and other charges

L

Pumping and supply-mains and road-improve-`

ments, etc. Miscellaneous charges.

·

·

Total amount

1,828,273

56,587

270,126 1

246,115

16,461

$2,417,562

The cost of the works has only exceeded the estimate by a small

amount.

The works were formally opened by His Excellency the Governor of Hong Kong, Sir Francis Henry May, K.C.M.G., LL.D., on the 2nd February, 1918, when a suitable commemoration stone was set at the termination of one of the parapets of the roadway over the dam.

Throughout the whole of the work the Author received the assistance of the Director of Public Works, Mr. William Chatham, C.M.G., M. Inst. C.E., and he wishes to express his indebtedness not only for the help given, but for the kindness and encouragement that he could always rely on.

Mr. Richard McNeil Henderson, Assoc, M. Inst, C.E., was the Chief Assistant-Engineer for the Taitam Tuk dam, and Mr. Edward Newhouse was Assistant Engineer for the pumping-mains and machinery foundations.

The Paper is accompanied by three tracings from some of which Plate 1 and the Figure in the text have been prepared, and by twelve photographs.

1

Approximate, the final account has not been settled.

The cost of the second section of the works has amounted to $2,417,562, which at the same rate of exchange as above is