Tai Lam Chung Reservoir project details, newspaper article 1951

IDJ has sent the following 1951 newspaper article about the proposed Tai Lam Reservoir Project which it suggests was about to be undertaken and would “solve for all time the Colony’s water-supply problem.”

If you would like further information about this reservoir please see our posted articles in Related Indhhk Articles, below.

This image shown on the Home Page of this article, and below, comes from Tymon Mellor’s article: Hong Kong Water Supply – Tai Lam Chung Reservoir

HF: I have retyped the article to aid legibility and searches.

$40 MILLION RESERVOIR FOR COLONY

Construction Work To Start Shortly

TAI LAM CHUNG VALLEY PROJECT DISCLOSED

A $40 million scheme for the construction of a new reservoir at Tai Lam Chung Valley is to be put into operation immediately, the China Mail learned officially this morning.

The reservoir will take from three to three and and a half years to complete. It will have storage capacity of 1,150 million gallons which, it is officially stated, will meet the present deficiency in the water supply position and remove any anxiety of a prolonged drought.

“On today’s consumption figures,” said an official, “the new reservoir would provide sufficient filtered water for a full 24-hour day service to be maintained throughout the year.”

The Tai Lam Ching Valley scheme has been under review since 1940, and the present construction proposals represent a first instalment of a bigger plan for solving for all time the Colony’s water-supply problem.

Here are the principal features of the new scheme.

Tai Lam Chung Reservoir: This will be formed by the construction of a 130 ft high concrete dam. The dam will be built thicker than normal for a dam of this height to allow for subsequent raising by an addition 50 ft. The top water level will be 150 feet above sea level and the reservoir will have a capacity of 1,150 million gallons stored in an area of about 200 acres.

Outlet Tunnel for the complete scheme, the size of pipe required to carry the water to the town is about 48 inches diameter.

Unfortunately, the only possible mine for this pipe to take would be along the main road from Castle Peak, but due to the twisting nature of the road, and the lack on any wide verge at the side, it would be quite impossible to lay such a large pipe on many sections of the highway.

TUNELLING

It is therefore planned to dodge the worst sections of the road by tunnelling. The first tunnel starts at the reservoir.

Instead of the usual arrangement of a draw-off tower to the dam, with the outlet pipes passing through the dam itself, the draw-off tower in this case will be built away from the dam and sited over the end of a tunnel which will carry the water directly under the hill at the southeast of the reservoir, emerging above Tsing Lung Tau.

An unusual feature of this tunnel will be an arrangement whereby the discharge from a catchwater over nine miles long will be directed into this tunnel near the Tsing Lung Tau outlet; and it will be done in such a way that if the flow from the catchwater exceeds the draw-off in the town, the surplus will flow back up the tunnel and will be discharged into the reservoir.

Although the catchwater is not included in the first stage of the scheme, the down shaft to the tunnel will have to be built. The tunnel will be about one and a third miles in length.

Main Aqueduct – This is to convey the water from the reservoir to the filters and service reservoir from which it will be distributed to the town. From Tsing Lung Tau to the next section will comprise a 30 ins diameter steel pipeline as far as the Brewery when it will again become a tunnel just before the site of the former Hume Pipe Works after which another 30 ins pipe will take it up a pumping station  near the bottom of the access road to Shing Mun at the town side of Tsuen Wan. Altogether 4.2 miles of pipeline and 2 miles of tunnel will be required.

TWO DAILY OUTPUT

HF: The following paragraph was sometimes difficult to read, even when enlarged.

Pumping Station. As the level of the water in the Reservoir will be a maximum of 100 feet it is impossible to get the water to the town entirely by gravity, in fact Tsuen Wan is about the limit. It will, therefore, be pumped from here to filters which are to be sited further up the Shing Mun access road at such an elevation that the water will flow from thence to the Service Reservoirs which supply the town. In the first stage the pumps will require to be of about 1,000 horse power, and 500h.p. for standby.

Filters. From the pumping station another 30 ins pipeline will discharge to Rapid Gravity Filters designed for an output of 10 million gallons per day.

Service Reservoir. From the filters the water will gravitate via another 30 ins pipeline to a service reservoir on the hill behind Laichikok. This will have a capacity of about 10 million gallons and be designed for future extension to 20 million.

Distribution: From the Laichkok Service Reservoir the water will be distributed to the town mains but a trunk main will also be laid to a further reservoir at Ma Tan Wei on the hill behind King George V School of about five million gallons capacity to feed the rapidly developing district on the East side of the peninsula.

LOCAL CONTRACTORS

It is proposed that all the work shall be let out on contract to local firms.

The reservoir, outlet tunnel, main aqueduct, pumping station, filters and service reservoir will be designed by the Consulting Engineers and the contracts supervised by a staff of engineers engaged by them on behalf of Government and working under the direction of the Director of Public Works.

By this means it is hoped that local firms will obtain the maximum possible benefit out of the vast expenditure.

The distribution system will be carried out by the Waterworks Office of the PWD as an ordinary item of new works construction.

It is hoped to be able to call for tenders for the dam in six or seven months time, and it is estimated that the entire project will take up three to three and a half years to complete.

An official recalling the background to the Tai Lam Chung Valley scheme, said that the first visit of Consulting Engineers took place in May 1940, and their report was not completed until December of that year.

It might well have been later but for the enterprise shown by the late Mr W.J.E. Binnie, the chief Consulting Engineer, who stranded in North Africa after the fall of France, succeeded in getting back to England only by signing on as a galley steward on a British tramp steamer.

The Consulting Engineers’ report confirmed the scheme as a whole, but it was not possible to settle the actual site.

Further boring work continued throughout 1941, revealing that the favoured site was not, in fact, very good, and boring started on a fourth site. Then the war intervened.

SCHEME COMPLETE

After the war it was necessary to obtain new drilling equipment, and boring was able to start in 1947. This made it possible for the fourth site, known as the Waterfall site, to be accepted as suitable for a reservoir, and the scheme, on paper, was thus complete.

The new problem created, however, was cost. From an original estimate of $21 million, the estimated cost in 1948 became around the $100 million mark. This introduced the question of whether a modified Tai Lam Chung scheme could be effected.

A scheme was drawn up and the Consulting Engineers were invited to visit the Colony once again to report on the new proposal.

Mr H.J.F. Gourley came here in June of this year, carried out his investigations, reported favourably, and his report, dated July 31, has been accepted by Government.

The present scheme, however, is not so much a modified version of the original proposals, as a first instalment complete in itself. The project can be extended as required to the limit of the resources of the valley.

Source: The China Mail 28th August 1951.

This article was first posted on 24th June 2021.

Related Indhhk articles:

1. Hong Kong Water Supply – Tai Lam Chung Reservoir
2. Tai Lam Chung Reservoir – construction images
3. Tai Lam Chung Reservoir – first built post-WW2 – construction images added
4. Binnie & Partners, engineering consultancy, Hong Kong reservoirs and more…
5. Sir Alexander Binnie, Binnie & Partners
6. Geoffrey Binnie, Engineer 1932–1936, Jubilee Dam, Shing Mun reservoir