PUBLIC WORKS AND UTILITIES
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and reduced the salinity, which by the end of 1974 was little different from that at the beginning of the year-94 ppm. The quality of the abstracted water remained satisfactory throughout the year.
The agreement with the People's Council of Kwangtung Province provides for the annual supply of 18,500 million gallons; in fact, the total delivery of water from October 1, 1973 to August 10, 1974 was 18,507 million gallons.
Demand for water continued to rise, but at a slower rate than in previous years, with a daily peak of 256.5 million gallons, a decrease of 0.2 per cent from the 1973 peak. The average consumption throughout the year was 210.5 million gallons per day, much the same as last year because of the slower increase in demand and the imposi- tion of restrictions. A total of 76,841 million gallons of potable water was consumed compared with 78,780 million gallons in 1973. In addition, 14,139 million gallons of salt water for flushing were supplied, 1.6 per cent more than 1973.
All civil engineering work related to the raising of Plover Cove dams, the con- struction of the extension pumping station at Tai Po Tau and the uprating and extension of Sha Tin Treatment Works was completed, pumping plant installed and the commissioning of filter beds to provide a total output of 175 million gallons a day well advanced. The uprating of Tai Mei Tuk Pumping Station continued, with one uprating pump installed and the second on site awaiting installation. An order was placed for a further extension pump for Tai Po Tau Pumping Station, to meet an- ticipated demands.
The drier summer enabled satisfactory progress to be made on the main contract for the construction of dams for High Island Reservoir, although some delays were caused when remedial works were required to seal leakage beneath the eastern sea cofferdam. Production of sand bitumen for the cofferdam filters started at the begin- ning of the year and on completion the plant was converted to the production of asphaltic concrete for the impervious, flexible cores for the main dams. With the closure of the eastern sea cofferdam, the reservoir area was pumped out and water collected from rains maintained at a low level for salt dilution. Dolosse casting was completed and the units placed in position and the casting yard was then converted to the production of Svee blocks. Work on access roads, tunnels and intakes con- tinued according to programme, with final tunnel breakthrough of the 24-mile tunnel system on August 19. The construction of the main pumping station progressed satisfactorily and contracts for constructing the lowland pumping stations were let. At Sha Tin, contracts were awarded and work started on construction of additional clarifiers and uprating of the filters to increase capacity of the treatment works from 175 to 240 million gallons a day. Breakthrough of the second Lion Rock Tunnel was made on April 29, and work on tunnel lining and pipe laying was ahead of schedule.
Work on the 40-million-gallon a day desalter continued satisfactorily, although the fuel crisis had repercussions on the manufacture and delivery of plant from Japan. This caused a delay in completion of the first unit, commissioning of which had to be re-scheduled for January 1975. All major civil engineering works were completed, with the emphasis changing to plant erection. Most senior posts were filled although difficulty was experienced in recruiting certain specialist staff.