Three Gorges Reservoir increases discharge to support spring irrigation

By Tan Maolin.

The Three Gorges Reservoir will increase water discharges this week to alleviate drought conditions along the Yangtze River, the Changjiang Water Resources Commission of the Ministry of Water Resources announced.

Photo by Wang Huifu.

From April 8-14, the dam will increase its water discharge speed to 10,000 cubic meters per second throughout the day to support spring irrigation in downstream farming regions, the authority said, without giving the original speed.

The move came as the Yangtze River Basin faces severe drought this year, with rainfall 30 percent below average. The hardest-hit middle and lower reaches have had nearly 40 percent less precipitation, leaving half of the basin in drought. Water levels at key monitoring stations are 2.3 to 3.3 meters below average, threatening agricultural water supplies.

Photo by Wang Gang.

The increased releases are expected to raise water levels by 0.7 to 2.0 meters along the riverbanks stretching from Shashi, Hubei Province, to Hukou County, Jiangxi Province, ensuring adequate irrigation for spring crops.

While addressing current water shortages, the Three Gorges Project continues to serve its primary flood control purpose. The dam can block 95 percent of floodwaters in the vulnerable Jingjiang section and two-thirds of flood peaks approaching Wuhan City, Hubei Province.

To date, the project has blocked 70 major floods, accumulating over 220 billion cubic meters of floodwater, including 21 numbered floods exceeding 50,000 cubic meters per second, and three mega-floods surpassing 70,000 cubic meters per second.