The development of a comprehensive flood prevention strategy for Hong Kong

Abstract

During the rainy season, flooding can occur in Hong Kong not only over floodplains in the rural areas but also at the older parts of the urban areas. A comprehensive flood prevention strategy has been progressively developed through a series of strategy studies in which considerations were given to the prevailing flooding problems, catchment topography and hydrology, long‐term development needs, socio‐economic conditions, management issues, and legal constraints. The primary component of the adopted strategy in Hong Kong is a set of flood protection standards for the planning and design of stormwater drainage systems. With these standards being set as targets, there are various structural measures for long‐term improvements, non‐structural measures as short‐term provisions, and planned preventive approaches of maintenance. Other non‐structural components include management and administrative measures such as land use planning and control, legislation, warning systems and hazard management plans. Apart from typical river training and on‐line capacity improvement, dedicated options including flood pumping schemes to protect building groups located on rural floodplains, and stormwater diversion and retention to minimize excavation works in densely populated urban areas have also been developed to suit the specific local conditions.

In this paper, the various phases of development of the flood prevention strategy are presented. The staged implementation of the strategy and the achievements secured are also discussed. Technical details about the various flood control strategy studies and the dedicated drainage improvement options are also given. With the comprehensive flood prevention strategy in place, there is no doubt that the drainage system in Hong Kong is being planned to meet the future demands and that the Government of the Hong Kong Special Administrative Region (HKSAR) is well on its way to providing adequate flood protection level and supporting sustainable development for the benefits of the community.

Keywords:

• Flood prevention strategy
• stormwater drainage
• diversion tunnel
• flood storage tanks
• Hong Kong