Urban Storm Flooding Management in Beijing

Abstract

Beijing is located in the piedmont plain of Taihang Mountains. It suffers from the floods formed in the Taihang Mountains as well as the local waterlogging. The precipitation in flood season (June to September) accounts for more than 80% of the annual precipitation, and it is often concentrated in late July to early August, which sometimes leads to serious urban flood disasters. For instance, in 1939 the precipitation in July and August was up to 1137 mm (recorded in Changping rain gauge); in August of 1963 the precipitation from 4th to 9th is more than 350 mm. Under the rapid urbanization in Beijing, the urban flood is becoming more serious, such as the pluvial disasters on 21st July of 2012. This chapter analysed the characteristics, evolution processes and main influencing factors of urban flood in Beijing based on the historical records. The four main measures of flood management in Beijing are summarized, which are: (1) upgrading and reconstruction of rainwater pumping stations; (2) improvement projects of small and medium rivers; (3) Sponge City construction; and (4) the West Suburb Storm-water Regulation Project. These measures have been put into use, and have played significant benefits on pluvial disaster mitigation in Beijing. On 20th July of 2016, the precipitation in urban area is 274 mm, which is more than that on 21st July of 2012, but there were no serious waterlogging events in urban area. In addition to early prevention measures, the flood warning and emergency management system has been established in Beijing. Beijing has also planned two deep tunnels to deliver overflowed rain water, which would greatly improve the defence standards of urban waterlogging in Beijing in the future. With the improvement of management and engineering measures, Beijing will be more resilient and safer under the heavy rains. The experiences of Beijing can also provide references for flood control in other cities.