Flood Prevention Infrastructure

The Drainage Services Department (DSD) is implementing a series of major flood control projects in the New Territories and in West Kowloon, costing about $13 billion.

    In the north-western New Territories, improvement works to about 12 kilometres of the lower and middle reaches of the Kam Tin River and the Shan Pui River in Yuen Long have been completed. The main drainage channels at Ngau Tam Mei and the upper reaches of the Kam Tin River near Kam Tin San Tsuen have been substantially completed and the flood risk around the areas has been relieved. Design work for the Yuen Long Bypass Floodway has been completed. Construction of the San Tin eastern main drainage channel commenced in October, and, upon its completion in 2005, the flood risk in San Tin will be reduced. Design work for the San Tin western drainage channel is under way.

    In the northern New Territories, one of the critical flood mitigation undertakings is the Shenzhen River Regulation Project, which is aimed at improving the downstream outlet for several major rivers in Sheung Shui and Ta Kwu Ling. The Stage I and Stage II works of the project have been completed. Together with the completion of river training works in the Lower River Indus and the River Beas, the traditional flood-prone villages in Lo Wu and Ho Sheung Heung areas are no longer at risk. Construction of the Shenzhen River Stage III works commenced in 2001 for completion in 2005. Design work for another five kilometres of drainage channels in the northern New Territories is also under way, including the River Ganges, Ma Wat and Kau Lung Hang channels. On completion of these river training works, the regional flooding problem in the northern New Territories will be alleviated.

    In addition to the major river training works, village flood pumping schemes have been implemented to protect low-lying villages from flood hazards. Construction of a village flood pumping scheme for Pok Wai in Yuen Long for solving the flooding problem in this 'black spot' was completed in August. Twenty schemes are now in operation, and five more schemes (at Chuk Yuen and Ha San Wai, Ma Tin, Shui Pin Wai, Wang Chau, and Mai Po Lo Wai and Mai Po San Tsuen) are under construction. Another two schemes, at Shui Pin Tsuen and Tai Kiu, are at the detailed design stage.

    In West Kowloon, good progress has been made on the Stage I and II drainage improvement works which are scheduled for completion in 2003 and substantial completion in 2004, respectively. In order to minimise the extent of road openings caused by the extensive drainage improvement works, construction of an underground flood storage tank — with a 100 000-cubic metre capacity — underneath the Tai Hang Tung Recreation Ground and a 1.8-kilometre stormwater transfer tunnel from Kowloon Tong to Kai Tak Nullah, commenced in early 2001 for completion in 2004. The Stage III works are also under way for completion in 2007.

    The department has completed seven Drainage Master Plan (DMP) Studies to review the condition and performance of the existing stormwater drainage systems in various flood-prone areas throughout Hong Kong. Phase I of the works under the Studies commenced in December 2001 in Yuen Long areas. Another DMP Study for southern Hong Kong Island commenced in September for completion in 2004, aiming at devising long-term and short-term measures for upgrading the stormwater drainage system so as to cope with current and future development needs.

    The department operates a preventive maintenance programme whereby the public drainage system is regularly inspected and desilted both before and during the rainy seasons. These preventive measures ensure that stormwater will be discharged effectively, and prevent blockages and overflows which may cause flooding and nuisance to the public.

    In 2002, the department maintained about 3 198 kilometres of watercourses, river channels and drains, from which about 54 600 cubic metres of silt were removed. To provide effective drainage services, the department operates a 24-hour drainage complaint hotline service to receive complaints from the public on blocked drains. The department also operates an Emergency and Storm Damage Organisation to ensure that emergency situations can be dealt with speedily and efficiently.

    The department continues to promote flood prevention through various public education activities, such as roving exhibitions with video shows at popular shopping centres, distribution of promotional leaflets and pamphlets, media site visit and press conferences. Since the launching of the 'Outreach Programme' in September 1999, professional engineers have visited more than 50 secondary schools and held seminars with the students to discuss their work and enhance understanding of the importance of flood prevention.