Cleanup mission given manpower and 4.5 billion yuan for projects to improve sewage treatment network around scenic spot. Hou Liqiang and Li Yingqing report from Dali, Yunnan.

For the past two months, Zhao Qiuhua has had to skip dinner most days, and he has rarely been able to get to bed before 2 am. Not that he minds, as he's helping to clean up China's treasured Erhai Lake.

This must-see scenic spot in Yunnan province has been affected by heavy pollution in recent years, yet Zhao and about 140 other government officials are working to restore the lake to how it looked more than five decades ago.

"We oversee the work and are in meetings all day and night, discussing the progress as well as potential solutions to problems we find," said Zhao, 29, deputy head of Xizhou township. "At the same time, we also need to carry out our day-to-day duties, to ensure things run smoothly in our towns and districts."

The Dali Bai autonomous prefecture, which also includes the ancient town of Dali, another major tourist attraction, deployed a significant amount of manpower when it launched the lake cleanup mission in January.

Although the number has not been disclosed, Zhao said about 80 of Xizhou's 100 officials are involved, along with 11 from the prefecture government and close to 50 village cadres.

Their main targets are guesthouses, restaurants and rural communities with low-quality or no sewage treatment equipment, which for years have been pumping raw sewage directly into the lake, as well as illegal construction and agricultural pollution.

Spring is usually a busy time for tourists heading to Erhai Lake, but few visitors could be found when China Daily reporters visited the area at the end of April.

Red banners carrying motivational slogans such as "If Erhai Lake is clean, Dali will thrive" or "Protecting Erhai Lake is like protecting your eyes" were hung over roads and plastered on billboards, walls and bridges.

Yet the brightly colored banners were in stark contrast to the white tape that officials had used to seal the doors of about 1,900 guesthouses and restaurants on the lake's northern, northeastern and western shores. All of them were ordered to close in early April to allow for an inspection of their wastewater treatment facilities, while a block was also placed on applications for new business licenses.

According to a notice from the prefecture government, these businesses will only be allowed to reopen once they can guarantee their wastewater can meet Grade 1, the highest level in the country's three-tier assessment system. Most now have only basic septic tanks, which means a considerable investment to meet the standards.

In addition, until work on a new sewage network around Erhai Lake is completed in June next year, businesses will be required to pay to regularly transport their wastewater to one of seven nearby treatment plants.

This will also hit owners in the pocket. Dali Aotuo Sewage Transport Co, for example, charges 1,200 yuan ($180) to extract and transport up to 3 cubic meters of sewage to a facility about 20 kilometers from the lake.

'Critical' condition

The annual number of visitors to Dali increased from 15 million in 2011 to 39 million last year, according to the prefecture government. By contrast, the authorities say the volume of pollutants discharged every year into Erhai Lake has risen by more than 50 percent since 2004, although no specific figures are available.

"The situation in the lake has been critical since early this year," said Fu Zhongjian, deputy director of rural development for the Yunnan Housing and Rural-Urban Development Department, which is supervising the cleanup campaign. He compared the lake to a hospital patient in need of emergency treatment.

Erhai Lake has been hit by at least two major outbreaks of blue-green algae, a toxic type of bacteria that develops on the water's surface. Caixin magazine reported that 22,857 tons of overgrowth caused by pollution, including algae, was removed using two boats fitted with specialist equipment between November and March.

In addition, the authorities are attempting to tackle pollution at the source, with the Yunnan Development and Reform Commission having approved 4.5 billion yuan in funding for public-private partnership projects to improve water quality in the lake.

According to the Dali government, 3.49 billion yuan will be spent during the 13th Five-Year Plan period, from 2016 to 2020, with private companies brought in to help construct sewage treatment plants, pipelines and pumping stations.

Cost of progress

While residents and business owners around the lake were generally supportive of the cleanup efforts, some who talked to China Daily criticized the government for failing to plan for the area's tourism boom.

Zhai Qiang, 35, moved from his native Beijing to Caicun, a village on the lake's western shore, in 2014 to open a guesthouse with 19 rooms. He has spent 4 million yuan on the business, yet he said the sudden order to close his doors had put that investment in jeopardy.

"The local government didn't communicate with us at all before they ordered the suspension," he said. He estimated his direct loss so far to be about 300,000 yuan, "and that's not to mention the 500,000 yuan my business can easily make every year".

In 2015, the authorities required him to install an underground tank that cost more than 70,000 yuan to filter his wastewater before it flowed into the lake so he could pass an environmental assessment, he said.

"We did everything as requested," Zhai said, but he added: "Tourism has been developing too fast. The government has failed to invest properly in infrastructure, including sewage pipelines. This is poor planning by the local government. We (businesses) are paying for this mistake."

Qiao Xiaolin, 37, until recently ran a guesthouse near Dali old town, about 5 km from Erhai Lake. When she first visited the lake, in 2012, she said there were few places to stay nearby, suggesting a gap in the market. It only required an investment of 300,000 yuan, and hotels could charge up to 2,000 yuan a night in the peak season, she said.

Yet she decided against it. "I had the money to open a guesthouse near the lake," Qiao said, "but I didn't want to do that because the money would be made at the cost of the natural environment, which is a valuable resource and can be impossible to restore once damaged."

Duan Shusheng, a man in his 30s from Zhoucheng village, just north of Caicun, was among the many residents who said they welcomed the government's cleanup mission.

"When I was young, the rivers that connected with the lake were so clean that you could see the bottom. We could drink from nature directly," he said. "We used to swim in the lake, but now the oil contamination that can be easily seen on the shore puts people off.

"I strongly support the cleanup work," Duan added. "We live on tourism, but only if the lake is clean will we see more tourists."

Contact the writers at houliqiang@chinadaily.com.cn

Tourists enjoy a walk around Erhai Lake, a scenic spot in Yunnan province that officials aim to restore to its former glory. Yang Zheng / For China Daily