China has demolished 300 dams and shut down most of the small hydropower stations on a major tributary of the upper Yangtze River to safeguard fish populations as part of an effort to restore the ecology of Asia’s longest waterway.

According to a report by the state news agency Xinhua on Monday, 300 of the 357 dams on Chishui He – also known as the Red River – had been dismantled by the end of December 2024. In addition, 342 out of 373 small hydropower stations have been decommissioned, enabling many rare fish species to resume their natural reproductive cycles, the Xinhua report said.

The Red River flows for more than 400km (249 miles) through the southwestern provinces of Yunnan, Guizhou and Sichuan. It is regarded by ecologists as the last refuge for rare and endemic fish species in the Yangtze’s upper reaches.

Over the decades, water flows have been increasingly blocked by the dense network of hydropower stations and dams, restricting water volumes downstream and occasionally even causing some sections to dry up entirely.

This has drastically reduced the amount of suitable habitat and spawning grounds. The stations also blocked the routes of migratory fish species between breeding grounds and non-breeding areas.