CO129-459 - Individuals - 1919 — Page 269

16

JAFFÉ ON HONG KONG WATERWORKS,

WVERFLOW

1400

WATER-LEVEL BELOW OVERFLOW.

TAITUM

TUK

RESERVOIR

R

8 8

GALLO

N S

MILLION

STORAGE

Fig. 7.

1300

PUMPINO- STATION

TUK

1200

1100

TAITAN

SOG 09-

[Selected

Funnel (treet level 400 00 gravitation supply to tšky al“Tuotowan Pumping Mains discharge inte

Basin at tunnd inlet,

DATUM. (LOW WATER SPRING-TIDE3)

900)

|TAITAM TUK RESERVOM

800

700

600

COOL

400

RAINFALL

CURVE,

300

200

TÄITAB TUK

RESERVOIR

104 HIFOUR DINE §.

JANE

TAÏTAM

REGERVOIRA

INTERMEDIATE ALGERVOIR

MARCH 29

APRILE

JUNE

JULY

ALG

Pumping commasand

KÖVERFLOWER

TAIYAN

SEPT

OCT.

00

GAUGE)

70 E

160

[40]

RÉSERVOIR

30

AON

DEC

20

TAITAM VALLEY: RAINFALL AND STATE OF RESERVOIRS, 1917.

INCHES (TAITAM

RAINFALL:

Papers.] LOW-LEVEL RESERVOIRS AND WORKS FOR PUMPING, 17

section works for stacking pipes, etc., a landing-stage, built at one end of it, permitting craft to come alongside. The landing- stage has now been extended by a reinforced-concrete jetty, 40 feet in width, which projects into sufficiently deep water to enable coal- junks and small craft generally to come alongside at all states of the tide, The piles for this jetty are 12 inches by 12 inches in cross section, 42 feet in length, and are formed of concrete composed of 1 cement, 1 sand and 23 broken granite (to inch). The reinforcement consists of four 1-inch diameter steel rods, one at each corner of the pile, laced together with 4-inch diameter steel ties at 12-inch intervals. The piles were driven through 18 feet of mud and clay to the hard, into which they penetrated for a depth of about 3 feet. The walings, bracing, decking, and bollards are also of reinforced concrete.

The pumping-station buildings are built of locally-made red bricks, cement mortar being used below ground and in piers, jambs, etc., and lime mortar for the remainder. The engine-house measures 129 feet by 30 feet, and the boiler-house 83 feet by 47 feet. A workshop, store, and quarters for the engine-room staff (both Chinese and European) are also provided. A feature of the station is the inclined flue up the hillside.

Two sets of pumping-machinery were installed for pumping from the Intermediate reservoir, each capable of lifting 14 million gallons in 24 hours against a maximum effective head of 400 feet. The sill of the gauge-basin, at the inlet of the tunnel for the gravitation supply to the city, over which water has to be pumped, is 383 feet above the level of the engine-house floor and 397 feet above the invert of the pump-pit. When pumping from the Intermediate reservoir the full power of the plant was not required, because the top-water level of that reservoir is 176 feet above the engine-house floor and the lowest draw-off is 96 feet; but, in view of the subsequent developments, the plant was designed to give the maximum efficiency when working against a head of about 350 feet. The engines are triple-expansion, vertical, having high-pressure cylinders 15 inches, intermediate 24 inches, and low-pressure 38 inches in diameter; the stroke is 30 inches and the revolu- tions 24 per minute. The pumps, three to each engine, have 12-inch diameter rams driven direct from the cross-heads by side rods straddling the crank-shaft. The boilers, two in number, are of the Lancashire type, working at a pressure of 135 lbs. per square inch, and are fitted with superheaters. A 6-ton travelling crane spans the engine-room.

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