Pollution control

As the area surrounding Baiyangdian industrialized, its water resources were strained and the lake suffered from drought and pollution caused by industrial runoff.

Chemicals carried by sewage poisoned the water and lake beds, decimating the aquatic life.

According to Xiong'an's department of ecology and environment, the quality of water in the lake was below Grade V, the worst in the country's five-tier quality system for surface water, in 2017.

Thanks to a series of measures that have been taken since the establishment of Xiong'an, the quality of water in the lake reached Grade III in 2021, and has stayed at that level for the past two years.

Yang Shan, an official with the department, said the improvement has occurred thanks to efforts to control the sources of pollution and intercept pollutants before rolling out measures for ecological remediation.

As a low-lying lake, Baiyangdian receives water from many small watercourses. This means that some pollutants may be carried into the lake from outside Xiong'an, especially during the rainy season.

As part of the efforts to address the problem, Yang said two constructed wetlands were built so that water from outside Xiong'an could be purified before flowing into Baiyangdian.

The official listed a series of measures Xiong'an authorities have taken to prevent wastewater generated inside the new area from entering Baiyangdian.

Currently, there are 7 sewage treatment plants in Xiong'an, the total daily capacity of which is 249,000 metric tons.

The quality of treated wastewater from these plants, which have been upgraded or built following high standards, can all reach Grade III, he added.

Water with a quality of Grade III is good enough for most aquatic organisms to survive.

To enhance rain and sewage diversion, 79 km of pipes were upgraded in urban areas in Anxin, Xiongxian and Rongcheng, Yang said.

In rural Xiong'an, all sewage disposal facilities have been upgraded. But as the aquatic environment in Baiyangdian keeps improving, these small facilities may not be enough to treat wastewater to the quality of water in the lake, he said.

To solve the problem, the treated wastewater from these small facilities is being diverted into ponds in 10 newly built rural parks, instead of being directly discharged into Baiyangdian, he said.

To further improve the ecological environment of the lake, 741 fish farms were cleared in 2018, Yang said. Following that, dredging has taken place from 2019 to last year, removing more than 11.9 million cubic meters of mud from the lake.

"Currently, both pollution control and ecological remediation programs are being conducted in Baiyangdian. But there have been increasingly fewer projects on pollution control, and this means that the pollution treatment work in the lake has almost been completed," he said.

In another move to help bring Baiyangdian back to life, a water replenishment program was launched in 2018, according to the Xiong'an government.

Over 5.9 billion cubic meters of water have been diverted into the lake, of which the South-to-North Water Diversion Project contributed 574 million tons.

Tian Yuan, an official with Xiong'an's department of construction and traffic management, said Baiyangdian is being supplemented by reclaimed water from sewage treatment plants.

Such reclaimed water is being discharged into water bodies that empty into Baiyangdian at a speed of 2 cubic meters per second, she said.