China is still facing an arduous mission to improve water quality as 30 percent of the country's major river drainage areas had not met the state required standard by the end of 2008. According to a report on the prevention and control of water pollution in 2008 released Wednesday, water quality of 80 out of the 115 key river drainage areas under surveillance, including Haihe River, the Three Gorges Reservoir Area, Chaohu Lake and the Yellow River, have attained the state standard.

Tao Detian, spokesman with the Ministry of the Environmental Protection, said the prevention and control of pollution in these rivers had basically reached the goal for 2008. However, he warned of an onerous task to improve the overall water quality.

Tao said ammonia nitrogen pollution was a major issue in several key rivers, and attributed water pollution to lack of investment for waste water disposal projects and low sewage treatment rate in urban districts.

Statistics from the ministry show that the government invested 5 billion yuan (731.92 million U.S. dollars) respectively in 2007 and 2008 to clean up four major rivers and three lakes. Another 7 billion yuan was spent in 2008 on building sewage treatment plants in cities, counties and townships.