January_1968 — Page 39

CIVIL ENGINEERING AND PUBLIC WORKS

Part IV

Plover Cove Water Scheme, Stage II

RIVER INDUS PUMPING STATION®

THE

HE River Indus flowing north- westward through the low-lying Sheung Shui plain to join the Sham Chun river near Lo Wu is the only genuine river in Hong Kong and has long been recognised as a potential source of water. However, it was so far from any reservoir that it only hecame practical to draw water from the river in 1960, when a 48 in, pipe- line was laid nearby to carry water imported from China to the Tai Lam Chung catchwater (see fig. 3:1). The Water Authority then established a small temporary diesel pumping station on the Indus delivering water into the same pipeline.

It was realised that very much greater quantities could be obtained from the river and feasibility studies for a large permanent pumping station associated with the Plover Cove Scheme were initiated in 1963. At about the same time a new agreement was negotiated with China for an annual water supply of 15,000 m.g., some of which was to be pumped from the East River. The delivery

TO

I LÀM CHUNG

CATCHWATER

1X43 IN.

STAGE 1 TUNNEL TO SHA TIN

TUNNEL

TAI PO TAU

TAU PASS CUL

by M.C.D. La Touche, MA, AMICE, AMIWE and R.J. Osborn, BA, AMICE

Water from the River Indus and from China is fed into the Plover Cove system at Tai Po Tau. This paper briefly describes the background to this arrangement and the hydrology of the area and gives details of the method of controlling the river, the pumping station building and the pumping plant. A brief ex- planation is also given of the control system for this small but highly sophisticated, engineering project.

pipelines from the pumping station were combined with the new pipeline for the additional Chinese water.

This pipeline, comprising twin .54 in. dia. pipes each approximately 4 miles long, discharges into the Tau Pass culvert, through which the water gravitates to Tai Po Tau and thence to the Sha Tin treatment works or Plover Cove reservoir as required. This culvert also diverts the head waters of one of the Indus tributaries direct to Tai Po Tau.

SHEUNG

SHUI

CANTON RAILWAY

J1X48 IN.

2X53 IN

FANLING

RIVER

The East River water gravitates from the Sham Chun reservoir just north of the border to Muk Wu, where it is pumped to Tau Pass. At the Indus pumping station a cross-

INDUS

LO

WU

CHUN

INDUS PUMPING STATION

2X48 IN.

MUK WU

RIVER GANGES

LEGEND

-

PUMPING STATION

H

STAGE I TUNNELS

connection enables three booster pumps to raise up to 30 m.g.d. to Tai Lam Chung through the original 48 in. pipeline. The booster pumps can also draw directly from the river (see fig. 3:2 and 3:3).

Apart from the booster pumps, there are ten pumps capable of draw- ing up to 200 m.g.d. from the river. The delivery pipes are grouped into two busmains which connect to the pipeline to Tau Pass. In general the East River water flowing from Muk Wu to Tau Pass will pass through the Indus pumping station without being re-pumped. Occasionally, however, when large quantities are being pump- ed from the river, the friction loss in

[WITH INTAKEY PIPELINE WITH NUMBER OF PIPES AND DIAMETER

FABRIDAM

GAUGING WEIR

BOUNDARIES:... PENING INOUS PUMPING

STATION CATCHMENT (13232 ACRES)

INDUS CATCHMENT DIVERTED DIRECTLY TO PLOVER COVE (3385 ACRES)

-+-- INTERNATIONAL

CHINA

the pipelines will raise the head above the capability of the pumps at Muk Wu. Under these circumstances the water arriving from Muk Wu will be discharged into the Indus river for sub- sequent re-pumping by the Indus pumps.

In view of the serious water shortage in 1963, the station was designed so that it could be brought into par- tial operation before comple- tion of the main structure. Although construction was not started until early 1964. the booster pumps were operational during the sum- mer of that year, pumping directly from the river, and three pumps capable of de-

FOLO

HARBOUR

PAT SIN RANGE

► ►

IRRIGATION RESERVIOR

TO PLOVER COVE RESERVOIR

Fig. 3:1

Far East Architect & Builder January, 1968

CONTOURS AT METRES INTERVAL

1000

YARDS 1000 500 0

2650 3000 YARDS

PLOVER COVE WATER SCHEME PIPELINE CONNECTIONS TO RIVER INDUS PUMPING STATION

* This paper by Mr. M.C.D. La Touche, senior engineer, Binnie and Partners, and Mr. R. J. Osborn, senior assistant resid- ent engineer, is the fourth in the series 'Some Aspects of Stage 11 of the Plover Cove Water Scheme'. It was presented to the Engineering Society of Hong Kong (Session 1966-67) and is published by permission of the society.

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