Towards better water security in North China

Water shortages and related environmental degradation in North China are major issues facing the country. As runoff from the mountainous parts of the region steadily decrease and water resources become overcommitted, serious water and environmental problems have resulted. These include drying-up of rivers, decline in groundwater levels, degradation of lakes and wetlands, and water pollution. Thus, 4000,km of the lower reaches of the Hai River - some 40% of its length - has experienced zero flows and, as result, parts of this river have become an ephemeral stream. The area of wetland within the Basin has decreased from 10,000 km(2) at the beginning of 1950s to 1,000 km(2) at present. Over-extraction of groundwater occurs beneath 70% of the North China Plain, with the total groundwater over-extraction estimated at 90 billion m(3). Thus, problems of water shortage and related environmental issues in North China have become the most significant limiting factors affecting sustainable development in this important region of China. This paper addresses the water security issues facing North China in the 21st Century using the Hai River basin as an example. We describe hydrologic cycles under changing environments, water-saving agriculture, assessment of water resource security, and efforts towards achieving integrated catchment management.