quay.
went on sale to the public in July. To assist in the design of the wall, model tests were commissioned to be carried out by the Hydraulics Research Station at Wallingford, England, and the Division was responsible for the liaison work. The Division was also involved in the preparation of the tender documents for the land tenure of the proposed container terminal lots.
Maintenance and Dredging
6.55. General maintenance and repairs were carried out to Government piers, seawalls, breakwaters, navigational markers and light beacons.
6.56. The two old dredgers continued to operate alternately using only one crew carrying out maintenance dredging at nullah outfalls and pier approaches. In addition, assistance was given to the Marine Department by dredging around harbour moorings so that they could be lifted for maintenance purposes. The total quantity of spoil removed during the year by these two dredgers amounted to 58,000 cu. yds.
6.57. The self-propelled hopper dredger carried out work in the Central Fairway and in Victoria Basin, H.M.S. Tamar. The total quantity of spoil removed was 305,000 cu. yds.
6.58. The Division's divers made inspections of piers, seawalls, pumphouses and pipelines, logging a total of 463 hours underwater.
Boring and Surveys
6.59. 268 marine boreholes totalling 7,024 ft. were sunk at various sites in the Colony waters. Also 304 probes totalling 7,524 ft. were sunk in site investigation for Kai Tak Runway Extension.
6.60. Current observations were carried out at Quarry Bay to supply information on tides to Marine Department. Echo-sounding surveys were made to check the sea bed level along the proposed Cross-Harbour Tunnel, the Cross-Harbour mains and the dredging at Central Fairway. Surveys were also carried out for checking the progress made on reclamations and site-formation, for measuring underwater work and for investigating sites of proposed works.
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