ENG-1999 — Page 467

THE ENVIRONMENT

1999 was about 6 100 per 100 millilitres, somewhat similar to the average concentration in 1998.

Progress has been made at bathing beaches, where small, private sewage-treatment facilities are often the dominant source of pollution. A combination of effective control and the provision of new sewerage has reversed a recent declining trend in the water quality at beaches.

In addition, pollution control is now having a positive effect, and river quality is slowly improving. The percentage of rivers in the 'good' and 'excellent' categories increased from 27 per cent in 1986 to 65 per cent in 1999, and the percentage in the 'bad' and 'very bad' categories fell from 52 per cent in 1986 to 16.8 per cent in 1999.

Sewage Treatment and Disposal

On a strategic level, sewage collected by the local sewerage network on both sides of Victoria Harbour will be directed to a sewage disposal system known as the Strategic Sewage Disposal Scheme (SSDS) for treatment and final disposal. The system is divided into Stage I, Stage II and Stage III/IV.

Stage I collects sewage from the urban areas of Kowloon, Tsuen Wan, Tseung Kwan O and the north-eastern part of Hong Kong Island. It will be completed in 2001, but its key element, the Stonecutters Island sewage treatment works, began operation in May 1997. When Stage I is completed, the system will intercept some 70 per cent of the sewage that used to flow into Victoria Harbour.

Stage II comprises upgrading the treatment system and a deep tunnel from Stonecutters Island to discharge the treated effluent in oceanic waters to the south of Hong Kong.

Stage III/IV will collect sewage from the north and south-western part of Hong Kong Island and transfer the effluent to Stonecutters Island for treatment. In the light of difficulties faced during Stage I works, an International Review Panel will be formed to examine whether the present plans remain the most cost-effective and environmentally friendly means for handling the sewage.

Sewerage Master Plans

Hong Kong has been divided into 16 sewerage master plan areas. The last plan was drawn up in 1996. The plans identified works estimated at $13.2 billion to bring the sewers up to standard in a phased improvement programme. The Chai Wan and Shau Kei Wan master plan was the first completed, in December 1997. This was followed by the Tsuen Wan, Kwai Chung and Tsing Yi master plan in November 1998. The remaining plans would be implemented by 2008.

To meet the revised population projections and the Government's housing programme, the EPD has started to review the sewerage master plans for various districts. The first three reviews cover Central and East Kowloon, Tsing Yi, Tuen Mun and the Outlying Islands. These reviews aim to check the adequacy of the plans and to identify additional sewerage infrastructure to meet future housing needs.

Sewer connections to individual properties are still in progress. Improvements in several parts of Hong Kong Island, Kowloon and the New Territories are well under way. Under the Water Pollution Control (Sewerage) Regulation, the EPD may require house owners to connect their waste water drains to new public sewers. In

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