Hong Kong Water Supply Shek Pik Reservoir – Part 1 Preparation Works
Tymon Mellor: With the rapidly increasing population in the post war Hong Kong, the availability of fresh water once more became a major problem. The poor financial situation had limited the territory’s options to overcome this, but after much discussion work commenced on Tai Lam Chung Reservoir in 1952. Before construction was complete, it was clear additional supplies would still be required to support the growing population, so the engineers turned to the as yet untapped Lantau Island and the development of the Shek Pik Scheme as a solution.
Lantau Island Pre-War Development
Until the development of the Shek Pik, Lantau Island was remote and undeveloped with a population of under 10,000. The largest village was Tai O with over 3,000 residents with a small boat building industry, salt pans and a fishing fleet supporting the local economy. The rest of the island consisted of isolated villages relying on a rural living of agriculture, pigs and ducks. There were no roads, just stone walking paths and only a limited ferry service[i].
Development of the island had been seen as an opportunity to address the overcrowded conditions on Hong Kong Island. Just before the Pacific War the Government established a Village Settlement Scheme[ii] focused on developing the areas in the Mui Wo area. A survey was undertaken in 1941 to confirm there were suitable water resources available at Cheung Sha, Tong Fuk, Shiu Hau and Shek Pik, sufficient for the needs of a 5,000 new population at each site. The new residents would be able to lease their own land, construct houses and cultivate or keep animals, providing a “direct and indirect assistance to their less fortunate neighbours”.
Cheung Chau Supply
In the post war environment, concern was raised over the water supply shortage on the island of Cheung Chau. By 1954 the island had a population of around 20,000 and was dependent on well water for its supply. During the dry season, junks had to be employed to carry water to supplement the dwindling supply[iii].
A concrete dam was proposed at Shap Long, creating a reservoir holding 35 million gallons of water. A small filtration plant and pump would utilise a 150mm diameter pipe to supply the water to the island, supplying 200,000 gallons a day. The system was completed and commissioned in 1956. Further details are captured in the article on Irrigation Reservoirs.
Tai O Supply
In May 1958, a new public water supply system was completed in Tai O replacing the unreliable wells[iv]. Work on the system commenced in October 1957 with the construction of a 10m high concrete gravity dam on a stream at Yi O, about 4.8km from the village. The dam impounded 500,000 gallons of water and came with a small screen tank and chlorination house located 300m down the hill. The system could supply 150,000 gallons of water a day, sufficient for the 10,000 residents of Tai O.
New Reservoir
By 1953 it was clear that even with the commissioning of the yet to be completed Tai Lam scheme, additional water sources would be required. The pre-war exploration of water suppliers indicated that the Shek Pik valley may be a suitable water source and location for a new reservoir. In November 1954, Messrs Binnie, Deacon and Gourley were commissioned to review the water resources of Lantau Island and they submitted their report in February of 1955. The consultant estimated that the total water supply for the Hong Kong Island and Kowloon would need to supply 90 to 96 million gallons a day to support a population of 3 million people. Taking in to account of existing supplies and the new Tai Lam reservoir, there was a shortfall of 30 million gallons a day. They recommended investigating locating a large reservoir at Shek Pik and Tung Chung, and within one month, funding was approved by the Executive Council and Finance Committee for the investigations[v].
It soon became apparent that the Tung Chung site would impact a number of villages and would result in a significant loss of agricultural land, and thus, further investigations were limited to just Shek Pik. The investigation report was submitted in November 1956 and much to the disappointment of the Government, it identified problems with the ground conditions at the dam site. A 12m layer of alluvium, containing boulders, gravels, sand and silts was identified across the centre of the valley. To complicate the situation, this was sitting on top of decomposed granite to a depth of 30m. These ground conditions would allow water to seep through the porous material and would not be suitable for the foundation of a dam. The cost of removing the poor material would be prohibitively expensive and further complicated by the proximity of the sea and the risk of water ingress in the deep excavations.
Shek Pik
The valley of Shek Pik was a remote part of the Colony, with no road access, no electricity, and water had to be obtained from rivers and wells. The valley had two main settlements, the larger Shek Pik had around 202 residents and Fan Pui was home to around 62 in 1955.
The village had an ancient history, with some of the families in Shek Pik tracing their ancestries back to the fifteenth century, and the village itself was probably older. The village of Fan Pui was first settled in around 1660 by a family from Kowloon and remained a single clan settlement until its demise. The valley had two smaller settlements, Kong Pui and Hang Chai, but few details of these have been recorded.
The only access to the villages was along stone paths, leading to the sea and over the hill to Tai O, thus the villagers were very independent and self-sufficient. Many of the villagers had never left the valley and had never seen cars, trains much less travelled in one. This would all change with the arrival of Western engineers and Chinese workmen in 1955 to start surveying the valley and undertaking the ground treatment trials. The villages were not happy with the new presence of Marine Police and the workers living in newly erected dormitories along with the quarrels, fights, opium smoking and heroin taking[vi] that came with them.
Grouting Trials
The consultant had an alternative solution to the traditional concrete groundwater cut-off, and instead, they proposed to grout the soil material using a new process developed by the French firm Soletanche, a specialist ground engineering company. This would have the effect of turning the loose and porous ground into homogeneous material by filling the voids with a mix of clay and cement material[vii]. To confirm the technique was suitable for this application, a trial was proposed to demonstrate the effectiveness of the solution with the actual ground conditions. The location of the trial was to be on the alignment of the dam so that if successful, it would be incorporated into the dam foundation, allowing a reservoir of 4,125 million gallons to be built in the Shek Pik valley, delivering supply of 21 million gallons a day.
In January 1957 the Government approved the scheme and negotiated a contract with Soil Mechanics Ltd and Soletanche to undertake the trial that could take up to 18 months to complete. Given the remoteness of the location, arrangements were made for the construction of living quarters, offices, marine jetty and the supply of water for the test. To minimise further delays, the Government commissioned Binnie Deacon & Gourley in May 1957 to commence design on the dam and procurement of long lead items such as the pumping equipment for the water supply. At Shek Pik, a detailed survey was undertaken of the area and additional site investigation carried out to support the preparation of the dam design. In total, around $1 million was spent on the preparation works in addition to the $2.5 million on the grouting trial.
The trial required the construction of a box 8.2m by 4m, using concrete piles to retain the alluvium to be grouted. A 2.1m surcharge was placed to allow grouting all the way up to the original surface. Then a mixture of bentonite and cement was injected into the ground. The impermeability of the ground was improved from 1.2 x 10-1 cm/sec to 1.2 x 10-5 cm/sec, sufficient to provide a suitable water cut-off for the dam[viii].
With a growing population and limited water supply, the Government had little choice but to expedite the works on the presumption of a successful trial. In the spring of 1956 residential water supplies had been cut down to 2.5 hours every second day. The commissioning of Tai Lam Reservoir in 1957 would provide only short-term relief. In May 1958 the trial was reported as a success and Government immediately decided to continue the grouting operation along with other mobilisation works. On the 1st October 1958, the Finance Committee approved a budget for $220 million for the full scheme. This would provide of a 5,400-million-gallon reservoir delivering 26 million gallons a day and boosting the Colony’s water storage capacity by 50%, new service reservoirs, trunk mains and the relocation of the villagers.
Construction Supervision
With the completion of the Tai Lam Chung, Brigadier G B Gifford Hull became the Chief Resident Engineer for Shek Pik until his retirement in December 1958. Starting with the Shing Mun scheme, he had been involved with all the major water works projects over a period of 26 years and was responsible for constructing 21 dams over his long career[ix].
Mr Gifford had a reputation of being a “law unto himself”, doing what he thought was best for the job and not necessarily recognising the broader issues. This became apparent when the District Lands Office was in negotiations with the villages for their land. He was frustrated with delays in progressing the new South Lantau Road, which had reached Cheung Sha but was making slow progress. He instructed the dam contractor to construct a jeep track across the hills to the north of Shui Hau (east of Shek Pik) upsetting the villagers by the lack of consultation. A geomancer, had to be called in to assess the impact to the fung shui, and who declared the new track as unacceptable. Construction of the jeep track was stopped and focus was put on the Public Works Department to complete the new road[x].
Following the retirement of Mr Gifford, he was replaced by Mr S C M Cutting, and from July 1961 Mr W Philips was appointed as the Chief Resident Engineer to complete the project.
Village Relocation
With the confirmation of the project, negotiations commenced with the village elders in early 1958. The Government wanted to acquire the land through negotiations rather than through compulsory purchase orders. The newly arrived District Officer James W Hayes was responsible for the successful negotiations and documented the experience in his book Friends & teachers: Hong Kong and its people, 1953-87.
Acquisition of the land necessary for the reservoir was undertaken in three stages. First was the farm land, completed in February 1959, then Fan Pui village, located on the alignment of the dam in October 1959, followed by the village of Shek Pik in November 1960.
The negotiations with the villages were difficult and at time frustrating for both sides, but in the end were successful and the areas were cleared in time to allow the reservoir construction works to continue. With the villages gone, the contractors commenced demolition and clearance of the areas on the following day.
The villagers from Fan Pui and the small hamlet of Hang Tsai, 73 people in total, were relocated to a new village at Tai Long Wan, to the west of Shek Pik. The residents of Shek Pik, elected to be relocated to a new apartment block in Tsuen Wan. Some of the older residents had to be carried out of the valley and onto the ferry to take them to their new homes and new ways of life.
In 1963, with the imminent opening of the reservoir, the SCMP interviewed the Shek Pik families. A total of 65 families consisting of more than 300 villagers had relocated to 133 flats in a new development in Tsuen Wan. One village representative noted, “It is a move for the better, and frankly, there is no similarity between the old life in Shek Pik and the new”[xi]. The former Fan Pui residents were equally satisfied with their new accommodation, and one reported, “the new house is much better. It has electricity and running water”[xii].
The total cost of the relocation was reported as $3,255,000[xiii].
Lantau Island Development
Prior to the construction of Shek Pik reservoir, Lantau was untouched by the modern world. However, the influx of workers, construction operations and land for development proved a catalyst for further development. The new infrastructure was not funded by the reservoir work, but it did take advantage and provided the necessary support to implement the works.
South Lantau Road
Following an initial survey in 1954, a new road was planned on the south of Lantau to improve communications for the residents and open up the island for development. With funding from the UK Government under the Colonial Development and Welfare Acts, work commenced in December 1955 on the initial section between Silvermine Bay and Cheung Sha[xiv]. With a peak construction workforce of 400 labourers, the Public Works Department completed the road within 18 months and opened it on the 3rd August 1957.
In January 1958, approval was given to extend the road to Shek Pik, supporting the growing number of workers and staff employed on the reservoir project. The road was completed 18 months later[xv]. However, following trials by KMB to establish a bus service, it was clear that the single lane road with passing places would need to be upgraded if a regular bus service was to be established[xvi]. Thus, in July 1959, work commenced on widening the road to two lanes[xvii].
Electricity
Before 1957, the only electricity supply to Lantau was available in Tai O, supplied by a generator operated by the Tai O Electric Company. This company was purchased by China Light and Power and in June 1955, CLP announced a $1 million project to install a submarine cable to supply the island[xviii]. By 1957 the cable had been laid between Tsing Lung Tau and north-east Lantau, poles had been erected across the hillside to Mui Wo[xix] and along to Shek Pik and Tai O. In December, 1957 the system was commissioned[xx].
Mui Wo Reclamation
The first reclamation at Mui Wo was for an initial 6.5 acres at Silvermine Bay and was authorised on 30th September 1961[xxi]. The area was located to the south of the existing Government pier and would eventually be part of a larger 36.7 acres of reclamation. It was intended that material from the Shek Pik reservoir workings would be used as fill material. The second phase of the reclamation was published on the 30th Mar 1962 for a further 9.6 acres along with a piled structure associated with a submarine water supple pipeline[xxii].
Mui Wo Hospital
With the influx of workers and staff, it became clear that a local medical facility would be required. Thus, in June 1960, a public hospital was opened at Cheung Sha for villagers and Government staff working on the Shek Pik reservoir[xxiii].
The facility had 17-beds in a two-storey brick structure to support the 2,500 south Lantau residents and forecasted 2,000 workers. The hospital had a resident Doctor, Dr J W B Palmer supported by four female nurses and a male nurse at the Shek Pik site. The hospital had limited capacity with emergency cases being transferred where possible by helicopter to the large hospitals on the Island and for less urgent cases sent to Silvermine Bay by Land Rover.
Police Station
With all the new developments and growing popularity of Silvermine Bay as a bathing beach, the temporary police post was replaced with a two-story building with accommodation for 30 police personnel[xxiv]. Construction of the building, located on the hillside overlooking the bay commenced in 1957 and was completed in 1958.
Construction
With the success of the grouting trial and the infrastructure in place to support the construction operation, work could commence on the Shek Pik scheme. Part 2 will explore the construction works and challenges faced by the engineers to build the scheme.
Images/Video
Hong Kong University Digital Repository
Sources:
[i] Report on the New Territories for the year 1939
[ii] Ample Water Supply All The Year Round, SCMP 9th April 1941
[iii] Gravity Dam To Be Built on Lantau Island, SCMP 7th Aug 1954
[iv] Piped Water Supply, SCMP 30 May 1958
[v] Hong Kong Annual Report, 1960
[vi] Friends and Teachers Hong Kong and Its People 1953-87, James Hayes 1996
[vii] 1956 – 1957 Annual Departmental Report, Director of Public Works
[viii] Augmentation of the water supply of Hong Kong, George A R Sheppard, 1960
[ix] ICE Obituary Brigadier Gordon Burnett Gifford Hull CBE, 1969
[x] Friends and Teachers Hong Kong and Its People 1953-87, James Hayes 1996
[xi] Shek Pik Move – A look back in gratitude, SCMP 21st Jan 1963
[xii] They left 300 years of tradition behind, SCMP 6th Oct 1959
[xiii] 1960 Hong Kong Annual Report
[xiv] New Lantao Island Motor Road Opened, SCCMP 4 Aug 1957
[xv] Extension of Lantao Road, SCMP 18th Jan 1958
[xvi] Bus Route Planned for Lantao, SCMP 21 May 1958
[xvii] Road on Lantao to be Widened for Bus Service, 30 Jul, 1959
[xviii] Electricity Project for Latao Island, SCMP 30 Jun 1955
[xix] Electricity for Lantao, SCMP 3 Sep 1957
[xx] Hong Kong Annual Report, 1957
[xxi] Reclamation at Silvermine Bay, SCMP 1st Oct 1960
[xxii] Notification, SCMP 14 Apr 1962
[xxiii] First Public Hospital in Lantao Opened, SCMP 15th Jun 1960
[xxiv] Silvermine Bay Police Post, SCMP 24 Aug 1957
This article was first posted on 19th May 2021.
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