ENG-2005 — Page 293

Land, Public Works and Utilities I 247

monitored exhausted sand borrow pits, which were then capped with clean mud on completion of filling to isolate the contaminants from the environment. The use of exhausted sand borrow pits for mud disposal is preferred as it has the dual benefits of providing much needed disposal capacity and restoring the seabed to its natural profile and state.

The CEDD is additionally responsible for managing disposal facilities for dredged and excavated sediment, and identifying and managing the supply of marine fill resources for development projects on behalf of the Marine Fill Committee.

The department also maintains a Fill Management Database on fill requirements, mud disposal and surplus excavated materials from major public and private projects to help the construction industry coordinate sources of fill materials and make the best use of surplus materials. All project data are available at the department's home page (www.cedd.gov.hk).

In connection with the management of Hong Kong's fill resources and mud disposal capacity, the department continues its geotechnical, environmental and ecological studies and monitoring to examine the effect of the dredging and disposal activities, and to investigate possible ways to minimise the impact on the marine environment.

Water Supplies

Water from Guangdong

To solve the water shortage problem and to meet the increasing demand, Hong Kong began to receive raw water from the Shenzhen Reservoir in Guangdong in 1960 when a scheme was completed for receiving a supply of 22.7 million cubic metres a year. The scheme was expanded in 1965 by constructing an 80-kilometre transfer system (the Dongshen Water Supply System) to deliver water from Dongjiang (East River) to Hong Kong via the Shenzhen Reservoir.

Dongjiang water is Hong Kong's major source of raw water. Under the current agreements, the supply of Dongjiang water to Hong Kong in the long term is guaranteed.

The Dongshen Water Supply System initially had an open channel design. To eliminate the water pollution problem, a closed aqueduct system was built. Since complete system started to operate in June 2003, there has been noticeable improvement in the quality of Dongjiang water supplied to Hong Kong.

Water Storage and Consumption

Full supply was maintained throughout the year. At the end of 2005, 461 million cubic metres of water were in storage, compared with 411 million cubic metres a year earlier. Hong Kong's two largest reservoirs, High Island and Plover Cove held a total of 414 million cubic metres. Rainfall of 3 215 millimetres, 45 per cent higher than the annual average of 2 214 millimetres, was recorded in 2005.

A peak daily consumption of 2.82 million cubic metres was recorded on September 15, 2005, compared with the 2004 peak of 2.79 million cubic metres. The