The Sup'ung Dam (), also referred to as the Shuifeng Dam and originally the Suihō Dam, is a

gravity dam A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by using only the weight of the material and its resistance against the foundation. Gravity dams are designed so that each section of the dam is ...

on the

Yalu River The Yalu River () or Amnok River () is a river on the border between China and North Korea. Together with the Tumen River to its east, and a small portion of Paektu Mountain, the Yalu forms the border between China and North Korea. Its valle ...

between

Kuandian Manchu Autonomous County Kuandian Manchu Autonomous County (; Manchu: ; Möllendorff: ''kuwandiyan manju beye dasangga siyan''), is a county of eastern Liaoning province, China, bordering North Korea to the southeast and Jilin in the northeast. It is under the administra ...

Liaoning Province ) , image_skyline = , image_alt = , image_caption = Clockwise: Mukden Palace in Shenyang, Xinghai Square in Dalian, Dalian coast, Yalu River at Dandong , image_map = Liaoning in China (+all claims hatched).svg , ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

and Sakju County,

North Pyongan Province North Pyongan Province (also spelled North P'yŏngan; ; ) is a western provinces of North Korea, province of North Korea. The province was formed in 1896 from the northern half of the former Pyongan Province, P'yŏng'an Province, remained a pro ...

North Korea North Korea, officially the Democratic People's Republic of Korea (DPRK), is a country in East Asia. It constitutes the northern half of the Korea, Korean Peninsula and borders China and Russia to the north at the Yalu River, Yalu (Amnok) an ...

. The dam was constructed by the Japanese between 1937 and 1943 in order to generate electricity and has been repaired and renovated several times throughout the years, mainly due to spillway damage from flooding. During the Korean War, the dam was bombed by the

United Nations Command United Nations Command (UNC or UN Command) is the multinational military force established to support the South Korea, Republic of Korea (South Korea) during and after the Korean War. It was the first attempt at collective security by the U ...

three separate times in order to disrupt power generation for the North Koreans. At the time of its completion, the dam was the largest in Asia, and power station was third-largest (after

Hoover Dam The Hoover Dam is a concrete arch-gravity dam in the Black Canyon of the Colorado, Black Canyon of the Colorado River (U.S.), Colorado River, on the border between the U.S. states of Nevada and Arizona. Constructed between 1931 and 1936, d ...

and Wilson Dam) hydroelectric power station in the world. It is still the largest hydroelectric power station on the Yalu (Korean: Amnok) River. Power produced at the dam's main 630 MW power station is evenly shared between China and North Korea. The dam is featured on the

national emblem of North Korea The National Emblem of the Democratic People's Republic of Korea is one of the national symbols of North Korea. Prominent features on the emblem are a red star, a hydroelectric plant (the Sup'ung Dam) and Mount Paektu. The design bears similar ...

Background

In 1937, during Japan's colonization of Korea, the Yalu Hydroelectric Company was established and in the same year construction began on the dam, with the Pyeongbuk Railway opening a rail line in 1939 to assist with the construction.朝鮮總督府官報 (The Public Journal of the Governor-General of Korea), Shōwa Nr. 3813, 3 October 1939 In 1941, the dam was complete with two 100 MW generators operational, and the emperor of

Manchukuo Manchukuo, officially known as the State of Manchuria prior to 1934 and the Empire of Great Manchuria thereafter, was a puppet state of the Empire of Japan in Northeast China that existed from 1932 until its dissolution in 1945. It was ostens ...

Puyi Puyi (7 February 190617 October 1967) was the final emperor of China, reigning as the eleventh monarch of the Qing dynasty from 1908 to 1912. When the Guangxu Emperor died without an heir, Empress Dowager Cixi picked his nephew Puyi, aged tw ...

, visited the dam.Kokubu, Hayato, 将軍様の鉄道 (Shōgun-sama no Tetsudō), Four more generators were later operational in 1943. The seventh generator was German-made and not delivered due to shipping difficulties during

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. At the time of its completion, the dam was the largest in Asia and third largest in the world. Power from the dam was used throughout the Korean peninsula and southern Manchuria (

at the time). After World War II, in 1947, the Soviet Union occupied the area, and dismantled and carried three of the seven generators to the

Irtysh River The Irtysh is a river in Russia, China, and Kazakhstan. It is the chief tributary of the Ob and is also the longest tributary in the world. The river's source lies in the Mongolian Altai in Dzungaria (the northern part of Xinjiang, China) cl ...

dam in

Kazakhstan Kazakhstan, officially the Republic of Kazakhstan, is a landlocked country primarily in Central Asia, with a European Kazakhstan, small portion in Eastern Europe. It borders Russia to the Kazakhstan–Russia border, north and west, China to th ...

. They were later re-installed during the 1950s.

Korean War attacks

The dam's power station and

transformer In electrical engineering, a transformer is a passive component that transfers electrical energy from one electrical circuit to another circuit, or multiple Electrical network, circuits. A varying current in any coil of the transformer produces ...

yard were targeted by the

three times during the

Korean War The Korean War (25 June 1950 – 27 July 1953) was an armed conflict on the Korean Peninsula fought between North Korea (Democratic People's Republic of Korea; DPRK) and South Korea (Republic of Korea; ROK) and their allies. North Korea was s ...

in order to disrupt power supply. Between 23 and 24 June 1952, the dam was attacked by 250 bombers and fighters, dropping 90 tons of munitions on the power station, transformer yard and auxiliary facilities. The power station was destroyed but the dam left intact. After intelligence indicated it may have been partially operational again, the power station was again targeted and disabled on 12 September 1952 by

B-29 The Boeing B-29 Superfortress is a retired American four-engined Propeller (aeronautics), propeller-driven heavy bomber, designed by Boeing and flown primarily by the United States during World War II and the Korean War. Named in allusion to ...

bombers. By 1 February 1953, it was believed that two generators had been repaired and were operational once again. This resulted in a third raid on the dam on 15 February which left the power station inoperable once again.

Repairs and renovations

Throughout the dam's history, it underwent several renovations and repairs. Flooding in 1946 damaged the stilling basin at the toe of the dam and destroyed its

spillway A spillway is a structure used to provide the controlled release of water downstream from a dam or levee, typically into the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure tha ...

, requiring repairs the next year. Between September 1949 and April 1950, in a second repair, the spillway and plunge pool were renovated. Between 1955 and 1958, permanent post-war repairs were made to the dam and power station. The generators removed by the Soviets were replaced and the installed capacity of the power station upgraded to 630 MW. In 1983, China began constructing an additional power station just downstream of the dam on their side of the river with two 67.5 MW generators. The first was commissioned in 1987 and the second in 1988. The most recent renovation occurred between 2009 and 2011 in order to improve the function of the dam's spillways. The US$24.5 million renovation was funded by

State Grid Corporation of China The State Grid Corporation of China (SGCC), commonly known as the State Grid, is a Chinese state-owned electric utility corporation. It is the largest utility company in the world. , State Grid is the world's third largest company overall by re ...

Design

The Supung is a tall and long concrete gravity dam with a crest elevation of . The dam's

consists of 26

sluice gate A sluice ( ) is a water channel containing a sluice gate, a type of lock to manage the water flow and water level. There are various types of sluice gates, including flap sluice gates and fan gates. Different depths are calculated when design s ...

s with a maximum discharge capacity of . An auxiliary spillway north of the dam consists of 16 sluice gates and has a maximum discharge capacity of . The dam's reservoir has a capacity of of which is active (or "useful") for power generation. The dam sits at the head of a

catchment area A catchment area in human geography, is the area from which a location, such as a city, service or institution, attracts a population that uses its services and economic opportunities. Catchment areas may be defined based on from where people are ...

and its reservoir has a surface area of . The original power station at the base of the dam contains six 105 MW

Francis turbine The Francis turbine is a type of water turbine. It is an inward-flow reaction turbine that combines radial and axial flow concepts. Francis turbines are the most common water turbine in use today, and can achieve over 95% efficiency. The pro ...

-generators which are afforded an average

hydraulic head Hydraulic head or piezometric head is a measurement related to liquid pressure (normalized by specific weight) and the liquid elevation above a vertical datum., 410 pages. See pp. 43–44., 650 pages. See p. 22, eq.3.2a. It is usually meas ...

of . The additional power station on China's side contains two 67.5 MW Francis turbine generators. The total installed capacity of the dam's power stations is 765 MW.

References

{{Commons category, Supung Dam Dams in China Dams in North Korea Gravity dams Hydroelectric power stations in Liaoning Hydroelectric power stations in North Korea China–North Korea border Dams completed in 1943 Dams on the Yalu River China–North Korea relations 1943 establishments in China 1943 establishments in Korea Energy infrastructure completed in 1943 Buildings and structures in North Pyongan Province Economy of Korea under Japanese rule Buildings and structures of Korea under Japanese rule

Background

Korean War attacks

Repairs and renovations

Design

See also

References