Dianchi: Anatomy of a Polluted Chinese Lake

An April 2000 report from U.S. Embassy Beijing

Summary: More than US$ 2 billion has been spent over the last seven years to clean up the Dianchi lake in China’s scenic Yunnan province. But the investments have produced little if any payoff, because they have not addressed non-point sources of pollution such as agricultural runoff. The central and provincial governments are now looking for innovative ways to address the problem.

A View That Once Inspired Poets

An Embassy EST officer recently visited southwest China’s Yunnan Province to investigate pollution of the Dianchi Lake. The Dianchi sits just south of the provincial capital of Kunming, a city of a million people. It covers an area of roughly 300 square kilometers. At its northern apex sits Daguan (grandview) Park, the centerpiece of which is a fluted-eaved viewing tower dedicated to a Qing Dynasty poet who was so moved by the view from the spot that he composed a 180-character ode that is now engraved on the tower’s walls. Visitors who climb the tower today are rewarded with a panorama of green slime. Blue-green algae, the product of severe eutrophication brought on by organic and chemical pollution, covers 20 square kilometers of the Dianchi, mostly in the northern part of the lake. The unsightly slime is even more apparent strolling along the shoreline of Haigeng Park — another major tourist attraction a few kilometers to the south — or riding the cable car across to the taoist grottoes in the Western Hills.

Tourism Implications Lead Authorities to Take Note

Since tourism is a mainstay of the Yunnan economy, the despoiling of the formerly scenic Dianchi has become a major concern of local and provincial officials. The Yunnan Research Institute Of Environmental Sciences, established in 1978, began studying the problem in the late ‘70s. In 1988 the provincial People’s Congress promulgated a set of regulations to protect the lake. Central government authorities in Beijing also began to take note of the problem. The State Council approved a comprehensive pollution control plan for the Dianchi in 1993, and the Dianchi was identified as one of three priority lakes under the 1995 national environmental strategy.

Left:  Unique Yunnan Tourist Spot:  American visitor David Armstrong Walks in the Forest Canopy at Xishuangbanna

According to a 1998 report by the State Environmental Protection Administration (SEPA), 185 million cubic meters of liquid waste was dumped into the Dianchi in 1995, of which roughly 50 million was industrial wastewater and 135 million was domestic sewage. Since 1993, more than US$ 2 billion — much of it financed through World Bank and Japanese Government loans — has been spent to clean up the lake. Most of the funds were used to build sewage treatment plants for Kunming. About 60 percent of the city’s sewage is now treated — more than three times the national average. Last year the government reportedly cajoled 249 of the 253 factories surrounding the Dianchi to stop dumping industrial waste into the lake.

Heavy Investment Has Not Curbed Pollution

The vice governor of Yunnan recently told the press that these measures had reduced Dianchi pollution considerably. But a world bank expert told Estoff the polltion-control efforts had had little observable effect. A local environmental expert confirmed that pollution levels in the upper Dianchi still regularly exceed the fifth (worst) level on China’s five-level water quality scale. Level five is defined as suitable for agricultural use but not fishable or swimmable. Water quality is somewhat better in the southern part, usually meeting the level-three (okay for swimming and fishing) or level-four (suitable for industrial and non-swimming recreational use) standards. The current target is to improve water quality throughout the lake to no worse than the level-four standard by 2010.

Failure to Address Non-Point Sources

The clean-up measures to date have failed to stem the pollution because they have focussed almost exclusively on point sources around the lake’s periphery. They have not addressed agricultural runoff or pollution of the lake’s tributaries. According to a recent press report, 80 percent of domestic sewage entering the 16 rivers that flow into the Dianchi is untreated. Meanwhile, heavy use of chemical fertilizers and pesticides on farm fields lying east of the lake leads to extremely high runoff of nitrates and phosphates. According to the 1998 SEPA report, 1,021 metric tons of phosphorous and 8,981 tons of nitrogen entered the lake in 1995. Concentrations of key pollutants were as follows:

Pollutant Concentrations in the Dianchi (1995)

(milligrams per liter)
 

*: milligrams per cubic meter

#: standards are based on Kjeldahl nitrogen; data are for total nitrogen.

Source: State Environmental Protection Administration
 
 

Beijing: Don’t Throw Good Money After Bad

Embassy sources report that Yunnan delegates lobbied hard at the recent National People’s Congress plenary for additional funds to clean up the Dianchi. Specifically, they sought to reprogram US$ 11 million in undisbursed funds from a 1993 World Bank environmental technical assistance loan to improve monitoring of Dianchi pollution. But sources said Premier Zhu Rongji was furious at reports indicating the billions spent to date on cleaning up the lake had failed to produce significant results, and he was not inclined to throw more money at the problem.

Shortly after the NPC plenary adjourned, however, the Ministry of Science And Technology (MOST) announced that it had awarded contracts to Tsinghua University and The Institute of Aquatic Organisms of the Chinese Academy of Sciences to develop and implement projects to control agricultural runoff and algal growth in the Dianchi. Most and the Yunnan provincial government will provide RMB 50 million (US$ 6 million) to fund the projects.

Experts contacted by the Embassy for this report preliminarily identified the following possible control strategies:improve the quality and application of chemical fertilizers: farmers currently over-apply nitrates and underapply potassium, according to a World Bank expert.