Guangdong turns inky rivers into scenic spots

For years, Huo Hanyu's canoe team had been roaming the waterbodies of southern China's Guangdong province and other provinces in order to train. There were many training bases to choose from, but the only one the team could not pick was in the city it plays for – Shenzhen, whose Maozhou River was once nicknamed by the locals as the "River of Ink."

The team finally returned and began training at its new home base in February this year, and Huo was amazed to see that the water no longer appeared black and thick as crude oil, while the notoriously foul odor was also entirely gone as well.

"Now I could enjoy the scenery during my hours of trainings every day, without having to worry about the potential damages of solid contaminants in unclean water on my kayak," Huo said.

Shenzhen's efforts to tackle water pollution

Shenzhen's large-scale efforts to clean its largest and once heavily polluted mother river came into full swing in 2016, the year after China called for nationwide efforts to address water pollution. 

In just four years, the city reported that it had reduced the river's ammonia nitrogen – one of the culprits of the inky water – to the lowest level since 1992.

The river's makeover is a snapshot of water treatment efforts across Guangdong province, which has strived to clean heavily polluted waters through systematic moves.

Over the past three decades, Guangdong has been China's fastest growing province, with Shenzhen at the center of its rapid economic boom. The city's population grew exponentially since 1990, from less than 1 million to over 17 million last year. Perhaps expectedly, its sewage treatment facilities and other such municipal infrastructure had not been able to keep up.

Municipal data shows that before major efforts to address the pollution of Maozhou River began, the daily sewage production in the basin was 1.03 million metric tons, while the five sewage treatment plants in the basin had the combined daily capacity of 700,000 metric tons. With almost one-third of untreated sewage directly discharged into it, Maozhou River became one of the most polluted rivers in the province.

Joint efforts with Dongguan

Over the few years since 2016, Shenzhen and its neighboring city Dongguan, both connected by the river, built and renovated four sewage treatment plants along the river, adding 850,000 metric tons of daily sewage capacity. In May that year, the largest sediment disposal plant in the world was also set up by the riverbank.

With the new facilities, the sediment in the river was turned into water, sand, and soil, and used for river replenishing, construction projects, and engineering backfill. Some of the residual materials even turned into permeable bricks paved along the river. Based on the large-scale practice, Shenzhen also worked out the country's first set of sediment disposal standards.

"The systematic moves contributed to a stable compliance of the water quality," said Fang Huaiyang, a senior engineer from the South China Institute of Environmental Sciences.

Fang said these achievements would have not been made without the efforts at all levels of the province or the active participation of the public. 

According to municipal data, the Shenzhen section of the river had as many as 11,000 workers at nearly 1,600 construction sites during the busiest time. They set a national record of laying 4.18 kilometers of pipes in one day. The Dongguan section also saw a peak of over 2,400 workers at around 360 construction sites paving pipes.

Their efforts contributed to the reduction of ammonia nitrogen concentration from as high as 24 mg/l in 2014 to less than 1 mg/l in 2019. The next year, the water quality in the lower reaches of the river reached Class IV on China's national standard, meaning it qualified for recreational use such as canoeing, and the quality in the upper reaches was even better.

"Shenzhen addressed the drawbacks accumulated in the past decades in years' time, and its systematic efforts and experience in Maozhou River charted a clear course for other heavily polluted rivers," Fang said.

Shantou's practice in transforming polluting industry

Shantou was another city in the province plagued by water pollution. Besides its high population density, a large source of pollutants in the city's Lianjiang River was its printing and dyeing industry. 

On Jan. 1, 2019, the city closed all 183 printing and dyeing companies scattered across the Lianjiang River basin, and began to cluster them into the industrial park with centralized sewage treatment, heating, and water supply.

"We are implementing strict criteria for entering the industrial park, and only those who are qualified can enter," said Wang Yegang, general manager of the industrial park's third-party operator.

So far, among the original 183 printing and dyeing companies along the river, 127 have moved in.

At 25, Zhong Guifa, general manager of Shantou Longfeng Print & Dyeing Co. Ltd., is the same age as his father when he started the company in 1989. Back then, the company did little in terms of sewage treatment before discharging it. Now, sewage treatment is a top requirement for running the business. 

"Despite some increase in sewage treatment costs, we should be visionary and bear the healthy and sustainable development of the industry in mind," Zhong said.

According to data from the city, the printing and dyeing companies in the industrial park together saw a 40% drop in water consumption, a 20% decrease in electricity consumption, a 25% increase in production efficiency, and an over 100% rise in production capacity.

Moreover, there are now 18 domestic sewage treatment plants and 8,070 kilometers of pipes along the 41-kilometer river section in Shantou, bringing the city's total sewage treatment capacity of its section of the Lianjiang River basin to over 106 metric tons per day.

As a result, the water quality of the national assessment section at Haimen Bay Bridge Sluice of Lianjiang River reached Class V (water for aesthetic environment) in January and maintained Class IV from February to April this year.

City officials, however, acknowledge that their work is far from over. "Water treatment is not a project that can be accomplished overnight," said Liu Yanfei, deputy head of the city's ecological environmental authority. "It requires systematic, targeted, science-based, and law-based efforts."

Further provincial-level moves taken in Guangdong

"The water treatment has contributed to local development," said Fang. "But the gains are certainly not only in economic terms, but also in the life of people along the rivers, who can feel the changes in a sensory way." The senior engineer said the next step will consist of long-term governance and ecological restoration.

Guangdong's government officials are in agreement, announcing moves to construct ecological belts along rivers and develop high-quality living environment for citizens.

"The river first, and then the banks," said Lun Xifan, deputy head of the Water Ecology Department of Shenzhen Municipal Ecology and Environment Bureau.

Last August, Shenzhen opened a 6-kilometer ecological belt along Maozhou River, incorporating a wetland park, a Maozhou River exhibition hall, a beer garden, a kids' playground, and several sports fields.