Erlongshan Reservoir in Jilin Province

Erlongshan Reservoir

Erlongshan Reservoir is located in the upper reaches of Dongliao River in Siping City, Jilin Province. It is a large-scale water conservancy project mainly for flood control, urban water supply, irrigation, and comprehensive utilization of flood control, power generation, fish culture, etc. The reservoir was built in 1943 and officially put into operation in 1950 with a designed storage capacity of 1.792 billion cubic meters. It is the largest reservoir in the East Liaohe River Basin and the main source of drinking water for nearly 600000 people in Siping City.

geographical position

Erlongshan Reservoir is a large reservoir on Dongliao River, which is mainly used for flood control, urban water supply, irrigation, power generation, fish culture and other comprehensive utilization. The dam site is located in Erlongshan village, Shiling Town, Lishu County, Jilin Province, 45 kilometers west of Siping City. The reservoir area spans Shiling Town, Siping City, Longshan Township, Gongzhuling City and Xiaogushan Town, Yitong Manchu Autonomous County. The reservoir has become a key flood control project of dongliaohe River, protecting 430000 people and 120000 hectares of arable land in 23 towns of Lishu, Gongzhuling and Shuangliao counties (cities) in the lower reaches, as well as the flood control safety of Beijing Harbin railway, pingqi railway and Changping expressway.

Historical evolution

Erlongshan Reservoir was built in 1943 during the period of the Japanese puppet regime. After the founding of new China, it was completed and put into operation in 1950. At that time, the main function of the reservoir was the water source project of dongliaohe irrigation area, and its flood control standard was only equivalent to the 50 year flood design and 200 year flood check. After 10 years of operation, it is found that the function of the reservoir can not meet the needs of disaster prevention and reduction as well as economic and social development. Therefore, in 1960, the reservoir was expanded, the original earth dam and concrete overflow dam were increased and thickened, and a water conveyance tunnel was added, which was completed in 1966. From 1972 to 1976, the power station of the reservoir was continued to be built, the capacity of the reservoir was increased in 1998, and the reinforcement project of the reservoir was completed from 2001 to 2004.

General situation of hydrometeorology

The reservoir is located in the middle reaches of the Dongliao River, above the dam site is the upper reaches of the Dongliao River, which is a low mountain and hilly area, with many hills on the left bank and many plains on the right bank. Along both banks of the river, there are open, cultivated land, willow clumps on the beach, curved river channel, steep river bank, and the altitude is between 200-500m. Below Erlongshan Reservoir, it is a microwave platform, with a general elevation of 200-250m and a small slope.

The area where the reservoir is located belongs to the temperate monsoon climate zone. It is hot and humid in summer, cold and less snow in winter. The average annual temperature is about 6 ℃ and the average annual precipitation is 677.9 mm. The catchment area above the dam site of the reservoir is 3799 square kilometers, with an average annual flow of 15.2 cubic meters per second.

Main buildings

The main structures of reservoir project include earth dam, concrete overflow dam, diversion tunnel and power station. The main dam is a 16 section clay core dam with a length of 419m, a crest width of 6m and a maximum height of 32.16m; the auxiliary dam is a homogeneous dam with a length of 99m, a crest width of 6m and a maximum height of 11.06m. The spillway is a gravity concrete dam with a total length of 100 meters, a dam height of 28 meters and a maximum discharge of 1243 cubic meters per second. The total length of the diversion tunnel is 333M, the diameter is 5.5m, and the maximum discharge is 293 cubic meters per second. The power station is a powerhouse at the back of the dam, which is equipped with four hydro generators. Combined with irrigation water, it generates electricity seasonally, with a total installed capacity of 8360 kW.

Facing problems

environmental pollution

The pollution sources of Erlongshan Reservoir are point source pollution, non-point source pollution and endogenous pollution. Point source pollution is mainly caused by industrial enterprises and domestic wastewater from upstream towns such as Liaoyuan City, Baiquan Town and Xiaogushan town. Non point source pollution is mainly caused by soil erosion of pesticides, chemical fertilizers and grazing excrement from farmers around the reservoir area. Endogenous pollution is a harmful substance released from the sediment of reservoir. Erlongshan Reservoir has been built for a long time, affected by point source and non-point source pollution, coupled with soil erosion, a large number of pollutants flow into the reservoir with water, forming endogenous pollution. The water quality of the reservoir was inferior to class V when the pollution was the most serious in 2004.

ecological damage

In the early years, the mountains around the reservoir were lush with trees, which used to be the imperial paddock of the Qing Dynasty. Later, the trees in the upper reaches of the reservoir were destroyed, causing serious deforestation and wasteland reclamation, forming barren mountains and barren hills, with about 171000 hectares of barren land. In the 1980s, local people managed the reservoir area and the upper reaches, planted trees and restored vegetation. The barren mountains and wasteland in the past have become oases.

Chinese PinYin : Ji Lin Sheng Er Long Shan Shui Ku