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INFRASTRUCTURE PROJECTS
Strategic Sewage Disposal Scheme
A scheme involving one of the world's largest, most compact treatment works and 70 kilometres of sewage conveyance tunnels is being implemented to collect and treat sewage from Hong Kong's older urban area.
The Strategic Sewage Disposal Scheme, which will lead to an improvement in water quality in Victoria Harbour, will be implemented under four stages targeted for completion by the end of the next decade.
Stage I is under construction and scheduled for completion in the second half of 2001. Sewage from the entire Kowloon urban area and north-eastern Hong Kong Island will be collected through 23.6 kilometres of rock tunnels at an average depth of 100 metres. It will receive a chemically enhanced primary treatment at the Stonecutters Island Sewage Treatment Works before being discharged into the open waters west of the harbour for disposal.
Stages III and IV will convey the sewage from the remaining urban area, in the northern and south-western parts of Hong Kong Island, to the treatment works through another tunnel conveyance system comprising 18.9 kilometres of deep tunnels and 1.7 kilometres of a tunnel through hilly terrain.
Stage II involves construction of 16.6 kilometres of deep tunnels conveying the effluent from the treatment works to Lamma Island where one of largest disinfection facilities in the world will be constructed. The disinfected effluent will be discharged in the open waters of the East Lamma Channel.
With the experience gained in the Stage I implementation, a panel of international and local experts on environmental protection, sewage treatment and engineering will be commissioned to review the current proposal for the scheme. Pending the completion of the review by the second half of 2000, a detailed implementation programme will be established with a view to putting the works in hand as early as practicable.
The overall cost of the scheme is estimated at about $25 billion.