The Unbong Dam, or Yunfeng Dam, is a concrete gravity dam on the Yalu River which borders China and North Korea. It is located 33 km (21 mi) northeast of Ji'an in Jilin Province, China and Chasŏng in Chagang Province, North Korea. The primary purpose of the dam is hydroelectric power generation and it supports a 400 MW power station. Construction of the dam had initially began in August 1942 but was halted in 1945 after the surrender of Japan ending World War II.[1] In October 1959, construction on the dam recommenced and in September 1965, the first of the four 100 MW Francis turbine-generators was operational. The last generator was operational on 4 April 1967. The 113.75 m (373 ft) tall dam creates a reservoir with a storage capacity of 3,895,000,000 m3 (3,157,728 acre⋅ft). The dam's spillway is an overflow type with 21 floodgates and has a maximum discharge of 21,900 m3/s (773,391 cu ft/s). The dam is located before a bend in the river and its power station is located on the other side of a ridge that meets the dam's right abutment. Water is delivered to the power station via two tunnels, 775 m (2,543 ft) and 759 m (2,490 ft) long. Generators 1 and 3 deliver power to China while 2 and 4 deliver to North Korea.[2][3]

Unbong Dam/Yunfeng Dam
View of the reservoir from the Chinese-side of the dam
Unbong Dam is located in China
Unbong Dam
Location of Unbong Dam/Yunfeng Dam in China
Official name운봉댐,운봉수력발전소,云峰水电站
CountryChina/North Korea
LocationJi'an/Chasŏng
Coordinates41°22′51″N 126°30′52″E / 41.38083°N 126.51444°E / 41.38083; 126.51444
StatusOperational
Construction began1959
Opening date1965
Dam and spillways
Type of damConcrete gravity
ImpoundsYalu River
Height113.75 m (373 ft)
Length828 m (2,717 ft)
Elevation at crest321.75 m (1,056 ft)
Spillway typeOverflow, 21 gates
Spillway capacity21,900 m3/s (773,391 cu ft/s)
Reservoir
Total capacity3,895,000,000 m3 (3,157,728 acre⋅ft)
Active capacity2,662,000,000 m3 (2,158,119 acre⋅ft)
Catchment area17,572 km2 (6,785 sq mi)
Normal elevation318.75 m (1,046 ft)
Power Station
Commission date1965-67
Hydraulic head89 m (292 ft) (design)
Turbines4 x 100 MW Francis-type
Installed capacity400 MW

See also

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References

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  1. ^ "Yunfeng Hydropower" (in Chinese). Neidri. Retrieved 5 September 2011.[dead link]
  2. ^ "Yunfeng Hydropower" (in Chinese). Zhejiang College of Water Conservancy and Hydropower. Archived from the original on 1 August 2014. Retrieved 5 September 2011.
  3. ^ "China's highest Concrete Gravity Dams". Chinese National Committee on Large Dams. Retrieved 5 September 2011.