How Yunnan Province Plans to Revive Its Dianchi Lake?


"China is sticking to an ecology-first path for green development and has already made remarkable achievements," Vice-Premier Han Zheng said during the United Nations biodiversity conference in Kunming earlier this month. The government would now put biodiversity at the heart of political and economic decision-making, he said.


There has been a gradual increase in water quality due to a significant amount of capital invested in pollution control in Yunnan province.

Image by Zhu Bing from Pixabay


China’s growing population led to a growing demand for water resources, and consequently to better environmental practices incentivized by the government. There has been a gradual increase in water quality due to a significant amount of capital invested in pollution control, Yunnan province itself is promising to reverse the damage done to its fragile local ecosystems over the last four decades, starting at Dianchi basin, a 300-square kilometer freshwater lake. 


Despite Yunnan province being mostly agricultural, the Dianchi basin has witnessed high industrial growth and boasts the highest population density within Kunming City. Some of the factors that contributed to its water quality becoming increasingly deteriorated are shallow water level, insufficient inflow, and the age stage of the Dianchi lake. Pollutants from agriculture, such as fertilizers and livestock waste, have increased over the last few decades, as has industrial pollution, enhanced by a lack of waste management programs and weak enforcement of environmental protection practices of the recent past. Furthermore, several decades ago the demands for development, industrialization, and progress led to the practice of land reclamation. Land reclamation required intense topographical and hydrological alterations to landmasses, which increased pollution by encouraging erosion and threatening biodiversity.


A decade of efforts and billions of dollars of spending at Dianchi has already seen the construction of 28 wastewater treatment plants handling more than 2 million tonnes of sewage a day. Wetland parks have been established, and polluted feeder rivers along the lake have been rehabilitated.


China divides water quality into five grades, with grade III suitable for human contact and drinking. But though water quality has been raised from "below grade V", meaning not even suitable for industrial use, it remains at grade IV - still severely polluted and hazardous to humans. Yunnan province officials could not provide a date for when it would be upgraded further. Scientists said decades of untreated industrial and household waste had ruined the ecosystem.


"Of course our target is to make the water better and better but scientifically speaking, in the short term it is going to be hard to get to grade III," said Huang Yuhong, vice-principal of a local research institute dedicated to protecting the lake.


The central government has accused local authorities of failing to develop a "clear understanding of the fragile and sensitive reality" of the local environment. A central government inspection team said in July that the "ecological space" around Dianchi was being "severely squeezed". It also accused local real estate developers of turning the protected zone of Changyao Mountain, located on the southeast edge of the lake, into a "cement mountain".


In 2008, an ambitious large-scale ecological restoration project of building a green wetland belt along the shore of Dianchi Lake was initiated under the “Kunming Urban Master Plan (2008-2020)”. In this Plan, the policy of “four recoveries, three restorations and one protection” – recovering the lake areas, forests and wetlands that were converted to farmlands, fishponds and residential areas to their original conditions, and relocating the residents - was first introduced. And later in 2010, wetlands rehabilitation and river ecological environment restoration were included in the “six master projects” to improve the water quality in Dianchi Lake. The effectiveness of investments in restoring wetlands to revive Dianchi Lake demonstrates wetland-based treatment a sustainable means of improving water quality. Despite multiple successful similar cases, there still exist areas for continued development.