TIANJIN－At dawn, Ren Zhaoyong started his daily patrol alongside the Grand Canal to check whether there was rubbish floating on the water or washed up on the shore.

Ren is the Party chief of Dongniantuozui village, Yangliuqing township in Xiqing district, Tianjin.

In January 2018, he was appointed as the river chief responsible for the protection of the water environment of the canal section in his village.

The Grand Canal, the world's longest man-made waterway, stretches 3,200 kilometers from Beijing to Hangzhou, capital of Zhejiang province.

The canal's history dates back more than 2,500 years, and it once served as an important waterway for transporting supplies to Beijing. A stretch of the canal of over 1,000 km was recognized as a world heritage site in 2014.

The 29.2-km Xiqing section of the Grand Canal not only meets industrial, agricultural and domestic needs, but also nourishes the local economy and culture.

Since the 1980s, many factories have been built along the canal. However, some of them secretly discharged industrial wastewater and sewage into the waterway and rubbish was piled on the shore.

"The water was as black as soy sauce, with a foul smell. No one was willing to go close to it," Ren said.

In 2015, the local government started a campaign to stop water pollution. Since 2017, a total of 245 companies in Yangliuqing have been shut down, relocated or upgraded.

Under the river chief system, 40 cadres at various levels are designated as river chiefs for environmental protection of the canal's Xiqing section.

Yu Shengmin, 57, who has worked as a cleaner along the waterway since 2012, said in the past cleaners salvaged about two metric tons of garbage every day.

"Nowadays, little garbage can be seen in the canal, except for some fallen leaves," Yu said.

Several other measures have been adopted to clear the waterway, including dredging the canal, growing plants that can absorb pollutants, restoring rock embankments and repairing dams.

Last year, the local government completed the construction of a sewage pipe network, along with treatment stations located in villages along the canal. After the wastewater had been treated, it was fit for agricultural use.

Li Baolei, deputy Party chief of Yangliuqing, said the improved water environment also has economic benefits.

"As the lives of the villagers improved and with more companies willing to invest here, we have realized the essence of the idea that clear waters and green mountains are as valuable as mountains of gold and silver," Li said.

Xinhua