Fanling
Lou Shui Heunge
ΑΚ
Hok Tau
Shaft AN
CIVIL ENGINEERING AND PUBLIC WORKS
Sha Tau Kok
Starling Inlet
Spoil dumping area 3
FIG. 2.1
Nam Chung
Shaft BB
BD
Chung Pui
BC
Chung Mei
AE
AR
AC
Re-alignment-
(Tung Tsz
AH
Ting Kok
AJ
to
AR
Tai Mei Tuk
AG
Fall
Plug AF
Fung Yuen
73
Shuen Wan
~Spoil dumping area
Main Dam
Spoil dumping area 18
PLOVER COVE
Shaft CB
5000
10000 feet
Part III
Tai Po
-Spoil dumping area 1A
Plover Cove Water Scheme, Stage II
Ο
NCE a suitable site for the main reservoir had been selected at Plover Cove, it was necessary to pro- vide a conduit to lead water to it for storage or back from it into the sup- ply system. It was also necessary to supplement the small natural catch- ment by collecting as much of the water from nearby catchments as was economically worthwhile. This is the purpose of the subsidiary tunnels, some of which carry water into the main tunnel, and others directly into Plover Cove.
Tenders for the construction of the tunnels and intakes between Plover Cove and Tai Po Tau were invited internationally in August, 1963. The contract was awarded to Sentab- Gammon in December, 1963 for the tendered sum of HK$96.6 million and preliminary works started on the site early in 1964.
General Description
Tunnels
The main tunnel connects the stream at Tai Po Tau with Plover Cove and is 6.1 miles long (see Fig. 2.1). It varies between 26 ft. and 30
Far East Architect & Builder December, 1967
Tolo Harbour
سا
General plan of tunnels
Tunnels and Intakes between Plover Cove and Tai Po Tau
by A.D. Garrod,* BSc, DIC, MICE, AMIWE
This paper describes the tunnels and surface works and gives an account of the methods used to drive and line the tunnels. Mention is made of a bad roof fall and the methods used to traverse bad ground. The methods of temporary support used in the tunnel were new to Hong Kong.
ft. lined equivalent diameter. Four subsidiary tunnels between 81⁄2 and 17 ft. dia. intercept streams and lead their water into the main tunnel, and a fifth intercepts two streams which flow into Starling Inlet, north of the Pat Sin range of hills near Sha Tau Kok, and diverts the water direct into Plover Cove.
In addition to the above, a tunnel near Lau Shui Heung conveys water from the Lau Shui Heung valley through an intervening ridge into the Hok Tau valley, which in turn is tapped by one of the branches from the main tunnel. Both the streams thus intercepted flow at present into the River Indus, north of the Pat Sin hills. A short tunnel which connects Plover Cove with Tolo Channel was used for the initial dewatering of the
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reservoir. There are 5.2 miles of subsidiary tunnels, making 11.3 miles of tunnel in all.
Water from the Tai Po river, the Tau Pass culvert, Stage I intakes, the River Indus and from China can be diverted into the main tunnel at Tai Po Tau. While the flow from most of these sources flows by gravity, water from the Indus and China has to be pumped to Tai Po Tau. During dry weather the main tunnel will be used to convey water back from
*Mr. A. D. Garrod is resident engineer for the Plover Cove Project. His paper 'Tunnels and Intakes between Plover Cove and Tai Po Tau' was presented to the Engineering Society of Hong Kong (Session 1966-1967) as part of a series entitled 'Some Aspects of Stage II of the Plover Cove Water Scheme'.
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