ENG-1989 — Page 253

LAND, PUBLIC WORKS AND UTILITIES

Port Works

One of the major responsibilities of the Civil Engineering Office of the Civil Engineer- ing Services Department is to implement and maintain engineering works within Hong Kong waters.

Projects in progress included reclamation adjacent to Kwai Chung Container Terminals No. 6 and No. 7 to provide land for container port operation, dredging works for deepening the approach channel to Container Terminal No. 7, reclamation of Hung Hom Bay to provide for general urban development and possibly for expansion of the Kowloon-Canton Railway goods yard, construction of 1 100 metres of breakwater for a new typhoon shelter at Shau Kei Wan, construction of piers and a seawater pumphouse for the Western Wholesale Market, and reclamations at Ap Lei Chau North, Siu Sai Wan and Lai Chi Kok Bay.

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Major projects completed in 1989 included the sand replenishment of Repulse Bay Beach and South Bay Beach, and the reclamation at Sam Ka Tsuen.

Geotechnical Control

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The Geotechnical Control Office of the Civil Engineering Services Department was established after the landslip disasters of the 1970's, and the control of geotechnical aspects of construction works in the interest of public safety continues to be its foremost duty. Checks were made on 5 453 design proposals in 1989. Landslip preventive work was also carried out on 28 slopes, requiring the expenditure of $77 million in the Landslip Preventive Measures Programme.

In addition, the office designed and is undertaking work for improvement of the stability and reduction of environmental hazards of the old sanitary landfill at Sai Tso Wan. This work to improve stability and control landfill gas migration is the first of its kind in Hong Kong.

The presence of cavernous marble beneath sites in the north-western New Territories has posed problems for development. To ensure safe development of buildings in the area, new legislation was enacted in November 1989 to empower the Building Authority with additional geotechnical controls. Resulting from studies in this area, four 1:5 000 scale geological maps were published for the areas around Yuen Long.

The Geotechnical Control Office operates the Landslip Warning System and a 24-hour emergency service to provide advice on landslips. Staff responded to calls for advice on 606 landslips and related incidents. Advice was also given to government departments on geotechnical aspects of 182 capital works projects. The Geotechnical Information Unit received more than 1 000 enquiries during the year.

The Hong Kong Geological Survey continues to publish 1:20 000 scale geological maps and memoirs. During 1989, geological maps for San Tin, Yuen Long, and Clear Water Bay were published, together with a geological memoir for the Western New Territories. New geological maps at a scale of 1:20 000 are now available for more than 50 per cent of the territory.

Three new guidance documents were published during 1989, consisting of two Model Specifications, for Prestressed Ground Anchors and Reinforced Fill Structures, and a Review of Design Methods for Excavation. With the publication in September of the Geotechnical Area Studies Programme Report for the Territory of Hong Kong, the release of the results of the regional 1:20 000 scale terrain classification was completed. The office also completed a study of the potential use of underground space in the form of man-made rock caverns, the results of which are being published.

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