The water level of Poyang Lake, the largest freshwater lake in China, recently dropped below 8 meters, reaching an extremely low level. Moreover, the speed at which the lake water is receding has broken records. The Hydrological Monitoring Center of Jiangxi Province has issued a blue alert for hydrological drought.
On October 9th at 19:00, the water level at the Xingzi station, a landmark hydrological station on Poyang Lake, measured 7.99 meters, falling below the extreme low water level of 8 meters, marking the second earliest recorded occurrence (the earliest being on September 6, 2022). The surface area of the lake connected to the Yangtze River is 291 square kilometers, with a volume of 925 million cubic meters, which has now shrunk to 1/13 and 1/31 of its capacity at the highest water level of the year.
As the water level of Poyang Lake continues to decline and falls below 8 meters, on October 10th, Jiangxi initiated a red alert for the protection of aquatic organisms during the dry season in Poyang Lake, as well as a red alert for the protection of Yangtze finless porpoises. As of 3:00 PM on October 15th, the water level at the Xingzi station further receded to 7.66 meters.
Due to above-average rainfall in Jiangxi Province compared to previous years, from mid-June this year, the water level at the Xingzi station began to rise. On July 4th at 14:00, the water level peaked at 21.56 meters, exceeding the warning level by 2.56 meters.
However, as August arrived, the average rainfall in Jiangxi Province was 20% lower compared to the same period in previous years. The water level in the main stream of the middle and lower reaches of the Yangtze River continued to drop, with the outflow from Poyang Lake being 40% below the average for the same period in previous years, leading to a rapid decline in water level at the Xingzi station. The monitoring data from the Hydrological Monitoring Center of Jiangxi Province showed that on August 24th, the water level at Xingzi station dropped below the average of the same period in previous years, and on September 10th, it fell to 11.98 meters, breaking the low-water record, 55 days earlier than the annual average, marking the sixth fastest occurrence on record.
The monitoring data also revealed that the time taken for the water level at the Xingzi station to drop from the low-water level to the even lower level was only 6 days, setting a new historical record as the fastest decline, surpassing the previous record in 2008, which took 7 days.
On October 9th, the Hydrological Monitoring Center of Jiangxi Province issued a blue alert for hydrological drought, urging water conservation measures to combat drought.
Public records show that Poyang Lake, also known as Pengli Lake, Pangze, Guanting Lake, Yanglan, and Danshi Lake, is located in the northern part of Jiangxi Province, surrounded by the cities of Jiujiang, Nanchang, and Shangrao. It is not only the largest freshwater lake in China but also the second largest lake in the country after Qinghai Lake.
Poyang Lake is one of the main tributaries of the middle and lower reaches of the Yangtze River. It is a significant lake in the Yangtze River Basin with characteristics of seasonal water fluctuation, water flow-through rate, and seasonal importance. The lake receives water from the Gan River, Fu River, Xin River, Rao River, and Xiu River (collectively known as the “Five Rivers”) in Jiangxi Province, as well as the Boyang River, Zhangtian River, and Tongjin River, which are then regulated before flowing into the Yangtze River at the mouth of the lake.
The water level of Poyang Lake is influenced by the water inflow from the “Five Rivers” and the support from the mainstream of the Yangtze River, making it a typical water-thoroughfare lake. The lake usually enters the flood season in April, which lasts for about half a year and transitions into the dry season around October, exhibiting a significant seasonal variation in water levels.
Poyang Lake plays a crucial role in regulating the water level of the Yangtze River, conserving water resources, improving local climate, and maintaining ecological balance in the surrounding areas.