THE MAINLAND'S 'who pollutes, who pays' decentralised approach to water resources management is partially behind Shenzhen's decision to build a closed-pipe 100-kilometre water diversion project, starting above Huiyang City on the Dongjiang River. Shenzhen is facing mounting pressure to increase its water supply. The provincial government, however, which has final management authority over the Dongjiang River, has been unable to come up with a comprehensive approach to supervising river resources, said Yao Yuzhen, deputy director-general of the Shenzhen Water Resources Bureau. Shenzhen is in the process of constructing a 103km pipeline to bring 350 million cubic metres of water annually from the Dongjiang River above Huiyang City to its Songzikeng Reservoir. When it is commissioned next year, the diversion project will transport 30 cubic metres of water per second through sealed pipes designed to protect the quality of the water from contamination by industrial or agricultural waste water as it passes through the Pearl River Delta. The Special Economic Zone government originally sought and received the province's permission to tap Dongjiang water at Dongguan City, but Dongguan authorities subsequently threw up barriers, forcing Shenzhen to look elsewhere. It naturally turned further north and upstream of the Dongjiang River's main pollution sources. Shenzhen's rapid economic development and scarcity of water demanded the project. The city consumed 860 million cubic metres of water last year for industrial and everyday use. By 2010 it is estimated the water usage in the city will more than double to 1.943 billion cubic metres. 'Older residents in Shenzhen still remember the drought of 1990 when water consumption was limited to only four hours a day,' Ms Yao said. She pointed out the Government's decentralised management of the Dongjiang River had come under increasing pressure from the fast-paced economic expansion throughout the Pearl River Delta. Inadequate enforcement of environmental laws, particularly over smaller townships and village enterprises, was also a serious concern. 'Cities along the Dongjiang are required to maintain the quality along their section of the river, but difficulties exist for implementing these regulations,' she said. 'Some factories that seriously pollute only need to relocate elsewhere and re-open again. We need to strengthen controls.' Ms Yao said that Shenzhen, like Hong Kong, was hampered by the declining quality of its water. 'Shenzhen's water is even worse than Hong Kong's because Hong Kong has larger reservoirs, where water can be stored for several days before it is utilised. 'What we need to do is reduce pollution [on the river],' she said.