An ‘international tourism destination of peerless beauty’ say the slogans hanging in the streets of Guilin, but one of the scenic city’s rivers has recently been home to sewage and garbage. In a country where environmentalists are charged with anti-government espionage, will the authorities intervene?

When Jianjun Xu woke up one morning in May 2015, the ground floor of his house in Gongcheng, Guilin, was flooded. After heavy rainstorms, the nearby Cha River swelled, sweeping away hundreds of homes. “The water was up to my knees,” he says. “It smelled awful and there was garbage floating in my living room.”

Xu didn’t understand how the floodwater had reached his street. Anti-flood barriers had been under construction since December 2012. Given the speed of Chinese infrastructure work, he thought the project had been completed. But instead of a construction site, he found a green river, its banks decorated with garbage.

Meanwhile, buses choke Guilin’s main boulevards morning and evening. Led by guides, large groups of tourists take selfies in front of local landmarks, such as the imposing Nengren Temple, and stroll the streets of Guilin’s old town and through its spacious parks. In the evening, they gather to enjoy a daily performance of an ancient opera or join local groups of elderly residents who dance to keep fit.

I've seen farmers throw dead chickens and pigs into the water, not far from where people are fishing. People ​drink that Jianjun Xu

From a rooftop cafe, one can see the Sun and Moon towers on Fir Lake as the city sprawl continues into the distance, giving way to bright green forests and hills, the stunning landscape Guilin is famous for. Throughout the municipality, red banners emblazoned with slogans like “an international tourism destination of peerless beauty” hang strategically, reminding newcomers of Guilin’s millennia-old reputation as China’s most beautiful city.

In nearby Yangshuo and Longsheng, karst peaks dominate a breathtaking landscape. The Li River carries visitors on bamboo rafts through the formations, as water bottles and plastic bits float alongside. Tourism accounted for close to 20% of the city’s economic output in 2015. The local government aims to increase that to over 27% by 2020 as part of their campaign to become China’s ecotourism destination.

Facebook Twitter Pinterest Construction waste discarded on the banks of the Cha River. Photograph: Kait Bolongaro

“As a less developed province, much of Guangxi remains a natural landscape,” explains Cheng Zhang, South China programme director at the International Union for Conservation of Nature. “This includes a great number of protected areas, such as nature reserves, forests and wetlands, which provide essential ‘nature’ for conducting ecotourism activities.”

Xu, though, isn’t concerned about tourism. As of November 2016, the anti-flood barriers remain unfinished. Construction companies and locals jettison their waste in the informal dumping ground wedged between the waterway, farmland and the city. More worrisome, the Cha River remains green.

“I have seen farmers throw dead chickens and pigs into the water, not far from where people are fishing. People drink that water,” says Xu.

The Guilin municipal government has taken efforts to improve the water quality of the Li River, one of the city’s main attractions. With a $100m (£80m) loan from the World Bank, officials are relocating industries, building wastewater treatment plants and landfills, and fighting pollution. However, the issues of other rivers like the Cha have been overlooked.

“Since leader Deng Xiaoping’s visit in the 1970s, the Li River has been a priority for the government because of its beauty,” says Ma Jun. “However, other rivers in Guilin are suffering from breakneck urbanisation and are more polluted and facing challenges. They are in less developed areas with weak sewage management and infrastructure.”

Greenpeace China told the Guardian that one third of the country’s rivers are contaminated. According to a report from the ministry of water resources in April 2016, 80% of shallow ground water wells are also polluted.

“In cities, you have wastewater from sewage, shops, factories and agriculture, which add other pollutants like persistent organics and heavy metals. It’s usually not fit for drinking or for crops,” explains Dr Wolfgang Kinzelbach from the Institute of Environmental Engineering in Zurich, Switzerland, an expert on China’s water management.

Facebook Twitter Pinterest Guilin’s old town is popular with tourists. Photograph: Kait Bolongaro

Despite Beijing’s increased transparency with air pollution, water pollution remains a taboo in China. Prominent environmentalists have been charged with espionage for speaking out about the situation. Many Chinese scientists who have studied water pollution in Guilin refused to be interviewed. “I’m not that brave. I don’t want to offend the government,” said one.

“Mining in the mountainous area in Guangxi [Guilin’s province] is a serious problem and it is an major reason why very clean water becomes polluted,” says Ma.

Water pollution causes birth defects, cancer, sterility … China is sacrificing a generation Dr Devra Davis

A 2016 study found that the Qingshitan reservoir, an important source of Guilin’s reservoir, was polluted, reporting above average nitrogen and organic carbon content. The report credits agricultural, industrial and domestic sources as the pollution culprits.

The results revealed that the water had an intermediate level of eutrophication, an excessive richness of nutrients that causes a dense growth of algae and suffocates animals such as fish. It also turns water green.

Eutrophication may lead to blooms of algae that can harm the liver and nervous system, explains Dr Urs von Gunten, an expert on China water resources from the Laboratory for Water Quality and Treatment in Lausanne, Switzerland.

Activists are concerned about the consequences of water pollution on the Chinese population. “Cancer villages” – small communities near polluting factories where cancer rates have soared far above the national average – have sprung up across the country.

“It takes a long time to restore river ecology when such pollution has occurred, meaning that generations could be affected by the pollution,” says Deng Tingting, toxics campaigner for Greenpeace East Asia.

Facebook Twitter Pinterest A farmer tills a plot of land wedged between the Cha River and a waste site. Photograph: Kait Bolongaro

In the Guangxi Zhuang autonomous region, where Guilin is located, a study of boarding schools found that drinking polluted water caused 80% of outbreaks of water-borne diseases.

“The range of human health impacts from water pollution extends from damage to the reproductive system, birth defects, cancer, sterility, as well as a whole host of neurological and cardiac diseases,” says Dr Devra Davis, an epidemiologist at the Environmental Health Trust. “China is sacrificing a generation because of this pollution issue.”

Back in Gongcheng, a farmer named Meng tends his crops on the banks of the Cha. Plastic bags and discarded household items line his property. “I am not worried about pollution,” he says. “I use the river water for my vegetables and they taste fine. My customers at the market never complain.”

Xu is less at ease with the situation. “Why is the water still green? Why is there garbage here instead of anti-flood barriers?” he asks with a deep sigh.

As part of Xi Jinping’s anti-corruption crusade, local officials have come under scrutiny from the central government. A source close to the local government says that in order to woo visiting national delegations, the municipal government organises outings to specific areas that flatter local officers, such as Hongyan and Aizhai.

Before an official visit from vice premier Wang Yang in 2015, a road to Hongyan was completed. “I find the timing suspicious,” says Xu.

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“Local governments must take greater responsibility for protecting China’s water environment,” says Tingting, the activist from Greenpeace.

There are signs that the threat posed by water pollution is being taken seriously. Beijing launched the Water Ten Plan in 2015, with the target that 93% of the country’s water sources should reach national standards by 2020. Municipalities are testing different energy alternatives, such as sludge-to-energy projects. Citizens can also report polluted rivers to the government via the Blue Sky app.

Such efforts may be too little, too late. “There is no solution that fits all problems,” says Von Gunten. “In my opinion, the protection of water resources is the most important factor.”

Others remain optimistic. “Change is not going to happen overnight, but China has promised it will tackle pollution as resolutely as it has tackled poverty,” says Debra Tan, who works for not-for-profit group China Water Risk.

On the banks of the Cha River, Xu is concerned that water pollution will worsen before any real change happens. He seems resigned.

“In Chinese, we have a saying: ‘People can always find a way to cope with government policies,’” he says. “I guess this pollution is something we are going to have to live with.”

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