At the end of last month, there were about 200,000 “river chiefs” like Weng and Jiang across China, according to the Ministry of Water Resources. Millions more are expected to be installed nationwide, after the top leadership decided late last year to give every waterway in the country a specific steward.

A similar programme for China’s bay areas, launched this year, is being expanded from five pilot schemes.

Across China, where officials are seeking to balance pollution control and economic growth, environmental issues have become an increasingly pressing cause of social instability. According to a report by the Chinese Academy of Social Sciences, half of the protests with more than 10,000 participants between 2001 and 2013 were sparked by concerns about pollution.

At the end of 2015, about a third of China’s surface water was still unfit for human use, according to a report by the environmental NGO Greenpeace, and last year alone, the central government allocated 13 billion yuan (US$1.94 billion) for water pollution control.

The Yangtze River Delta region that surrounds Lake Tai has taken the lead in treating its rivers via the river chief system.

The region, which comprises the provinces of Jiangsu and Zhejiang and the municipality of Shanghai, has seen some improvement in water quality since the river chief system was adopted, according to government monitoring data.

The first river chief was appointed by the government of Wuxi, a city in Jiangsu on the northern shore of Lake Tai, to treat a blue-green algae bloom 10 years ago. They were then installed across the entire province in 2012 and neighbouring Zhejiang in 2013, with their main duties being to organise check-ups and respond to public complaints.

Greenpeace East Asia campaigner Deng Tingting said “one hopeful sign is that Jiangsu, where the river chief system originated, has seen significant improvement in water quality over the past six years”.

She said the proportion of Jiangsu’s surface water categorised as “fit for human use” (grades 1 to 3) had increased from 35.5 per cent in 2011 to 63.9 per cent last year.

In Shanghai, however, things have worsened in the past couple of years. In 2014, about a quarter of Shanghai’s water was regarded as fit for human use, but last year, that dropped to just 16 per cent, even though the portion in the worst category – worse than grade 5 – dropped from 49 per cent in 2014 to 34 per cent in 2016.

And the delta region is still home to many towns like Jiapu, in Zhejiang, where residents complain progress has been too slow given the huge sum of money spent. Others say the system only provides band-aid responses, while ignoring the underlying causes of pollution.

The river chiefs are all government cadres, from provincial governors to village committee heads, each in charge of one particular river or segment of river. The more important the river is, the higher ranking the official.

Their names and mobile phone numbers are posted on a sign beside the river, usually along with information about the river itself.

Dongtiao Creek, one of more than 200 streams flowing into Lake Tai and a drinking water source for the Yuhang district in Hangzhou, Zhejiang’s capital, had improved a lot since the system was adopted, said 45-year-old Yuhang resident Hu Guoqiang.

“When I was little we drank the water from Dongtiao Creek directly,” he said. “When I worked for local quarries and transported stones along the river in my 20s, the water was black. Now it’s better and we’ve started swimming there again.”

Hu said when a resident dialled the river chief’s number to complain about pollutants, there was usually a response.

Hangzhou also has more than 50 volunteer, non-government river stewards, including environmental activists and lawyers, who conduct check-ups and work with government river chiefs.

One of them is Dong Zheng, from local NGO Green Zhejiang.

He said the biggest headache was that when he spent his free time checking up on his river, it was often on weekends and holidays, when the government river chiefs, who stuck to official working hours, were enjoying their days off.

“They keep their mobile phones on but will often say they’re out of town and cannot handle the matter right away,” said Dong, who’s responsible for a 1km stretch of the Jiangjun River. “I understand it’s their spare time but this is leading to inefficiency.”

Li Xiaokan, the head of Jiaodao village in Zhejiang’s Wuyi county, has been Baxian Creek’s river chief since the system was first introduced and said he patrolled the stretch in his village every day.

Although there were not many sources of industrial pollutants along waterways in the mountainous area, Li said many residents still dumped garbage next to them, and when it rained the garbage ended up in the water.

“If I find rubbish in the river, I need to ask a cleaner to clear it up,” he said.

Before the river chief system was adopted, a number of different departments tasked with tackling river pollution in the delta region, including water resources and environmental protection, passed the buck when someone filed a complaint.

“Everybody had the responsibility, which meant that nobody took the responsibility,” said Professor Zheng Zheng, a river pollution expert at Shanghai’s Fudan University. “In this sense, the river chief system reduces the possibility of shirking responsibility.”

He said that because the river chief was a powerful person in the corresponding government, usually a top official, he was able to use resources and get things done.

The system was also meaningful because “it tells people that the government takes this issue very seriously”, Zheng added.

In Jiapu, where nearly every household is a small textile factory, synthetic fabrics are produced on water-jet looms. The pollution comes from the oils and stiffening agents used in the weaving process as the water shuttles the thread back and forth.

Gu Genlin, a 73-year-old Jiapu resident, said he used to live beside the Qinjiabanggang, but had to move due to the serious pollution in the river.

“In the worst times, the river turned black in summer, and sometimes white as milk,” he said.

His wife died a couple of years ago from blood poisoning, which the family suspected was caused by polluted water.

“I’ve taken thousands of photos of the polluted rivers in the neighbourhood for seven years and petitioned to all levels of governments, and it’s still the same,” he said.

He said there were several sewage processing plants in Jiapu which led to the biggest one, right beside the lake.

River chief Weng said he had instigated an underground piping project to minimise the amount of waste flowing into the town’s waterways.

“In the past, the pipes were uncovered along the river banks, and when some of them sprang leaks, the sewage went to the rivers directly,” he said. “We’ve spent 70 million yuan to solve this problem.”

Weng said the waste water was pumped into the lake after treatment. “Compared with the rivers here, Lake Tai is like an ocean, which has a bigger ability to self-adjust,” he said.

But asked whether the water was now suitable for human use, Weng said “there’s still a long way to go”.

Wu Lihong, an environmental activist who’s been observing and fighting water pollution in the Lake Tai area for two decades, said the river chief system did not address the underlying cause of the problem

“Those factories are the source of pollution, but they simply didn’t have the guts to close them after all these years,” he said. “I’ve seen glimmers of hope [elsewhere in the Lake Tai area], but not here [in Jiapu]. It’s almost the same as what I saw 15 years ago.”

Ma Jun, director of the Institute of Public & Environmental Affairs, a Beijing-based NGO, agreed that the appointment of river chiefs was far from enough to treat China’s polluted waterways.

“It’s a very Chinese characteristic, doing things top down,” he said. “But how to ensure the message is delivered from the bottom to the top is a big issue.”

This is the first in a three-part series on pollution in China, exploring the country’s balancing act between economic growth and efforts to improve its air, water and waste management.