China has announced a project to clean up the Yangtze River, the world's fourth longest waterway, due to increasingly severe pollution from silt and untreated waste. The blueprint, approved last month and announced yesterday by Xinhua, will target five major cities along the 6,000km river - Shanghai, Nanjing, Wuhan, Chongqing and Panzhihua. The project will require the cities to meet the government's treatment standards for 60 per cent of their waste water before 2010 and 70 per cent after that time, Xinhua said. In addition, upstream cities will also be required to increase their water storage capacity and improve their ability to treat rubbish and solid waste. The move to clean up the Yangtze has taken on added importance because of the Three Gorges Dam and another project which aims to transport water from southern China to the parched north, it said. China will dam the Yangtze for the second time next month to allow construction of the Three Gorges project. Builders plan to flood the reservoir by the end of the first quarter of next year and have asked local governments to clear debris, waste water and solid rubbish that could pollute the water. Analysts say the Three Gorges Dam, due for completion in 2009, will slow the flow of the Yangtze, which could worsen pollution. The Ministry of Water Resources, which is overseeing the clean-up, will also try to control soil erosion and reduce the amount of excess nutrients caused by run-off from soil treated with chemical fertiliser for three major lakes near the Yangtze. They are the Tai Lake, located in the eastern provinces of Jiangsu and Zhejiang, Chao Lake in Anhui province and Dianchi Lake in the southwest province of Yunnan. As part of the plan, companies along the river must comply with government rules for industrial waste while cities and towns in the Three Gorges area must properly dispose of rubbish, Xinhua said. The Yangtze River catchment area discharged 23.4 billion tonnes of waste water in 2000, up nearly 24 per cent from 1998. 'For the East China Sea, the main source of pollution is the Yangtze River,' said Luo Feiqiang, an official of the oceanic bureau in the coastal city of Ningbo. He said the main problem was industrial pollution, including heavy metals, which could find their way into the food chain. The National Oceanic Administration was now studying the problem and planned to release a report, Mr Luo said. The quality of China's water resources - including rivers, lakes and coastal waters - is generally poor, the World Bank said in a report issued last year. However, there has been improvement in some of the larger rivers over the past 10 years despite the fact the rest have deteriorated.