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LAND, PUBLIC WORKS AND UTILITIES
Port Works
Some 600 metres of seawall was constructed at Ap Lei Chau, enabling four hectares of seabed to be reclaimed, and providing land for roads, boatyards and other industrial and government uses. At Aberdeen, a berthing pier was built for the Marine Police.
Other port works under construction include an extension to a public pier at Cheung Chau and a 180-metre breakwater for naval vessels at Stonecutters Island.
Geotechnical Control
The Geotechnical Control Office (GCO) of the Civil Engineering Services Department continued to exercise control over the geotechnical aspects of public and private building and civil engineering works in the interest of public safety. All new design proposals for works which involved site formation, slopes, earth retaining structures and deep exca- vations were checked for compliance with the necessary standards of safety. A total of 4 400 design proposals were checked. The Geotechnical Control Office also attended or inspected landslip incidents, and gave advice on emergency precautions, evacuation and remedial works.
Under the geotechnical advisory services for government projects, the GCO undertook 46 geotechnical designs for 46 projects and gave advice on 122 other projects to depart- ments in the Lands and Works group.
The long-term Landslip Preventive Measures Programme continued at an expenditure of about $55 million per year. In 1986, stabilisation works were completed on 42 slopes and retaining walls at a cost of $44 million, and works commenced on a further 61 slopes and walls. Stabilisation works were also carried out on 13 slopes affecting squatters.
The Geotechnical Area Studies Programme Report for Hong Kong and Kowloon was released to the public in the latter part of the year. This is the first of 12 reports covering the territory which summarise geotechnical constraints to land development for use in planning and engineering feasibility studies.
The first of the new Hong Kong Geological Survey 1:20 000 scale maps and explanatory memoirs, covering Sha Tin, Kowloon and Hong Kong Island, were made available to the public by the GCO. The maps and memoirs contain geological information both on land and offshore, in considerably greater detail than has been attempted previously.
A comprehensive archive of geological data including maps, a rock collection, thin sections and photomicrographs, and field photographs has been built up and forms the basis of an enquiry service offered to members of the public.
Quarrying and Materials Testing
The Geotechnical Control Office of the Civil Engineering Services Department manages two government quarries, and supervises six private quarries and two private rock-crushing plants operated under government contract. With the supplement of rock crushing plants associated with development works, the total production in the territory amounted to approximately 11 million tonnes. The total consumption of aggregates, crushed rock fines and sand was approximately 16 million tonnes. The balance of five million tonnes was imported mainly from China.
The GCO also operates several laboratories situated throughout the territory to provide a testing and advisory service to government departments on a wide range of construction materials with the emphasis mainly on soil, rock, reinforcing steel and concrete, but including timber, aggregates, and bituminous products. More than 220 000 tests were carried out during the year.