The Saemangeum Seawall (), on the south-west coast of the

Korean peninsula Korea is a peninsular region in East Asia consisting of the Korean Peninsula, Jeju Island, and smaller islands. Since the end of World War II in 1945, it has been politically divided at or near the 38th parallel between North Korea (Dem ...

, is the world's longest man-made dyke, measuring . It runs between two headlands, and separates the

Yellow Sea The Yellow Sea, also known as the North Sea, is a marginal sea of the Western Pacific Ocean located between mainland China and the Korean Peninsula, and can be considered the northwestern part of the East China Sea. Names It is one of four ...

and the former Saemangeum estuary. It was built to reclaim land for both agriculture and urban uses, including industrial uses, and 401 km² of the estuary was planned to be developed into an artificial lake (118 km²) and relaimed land (283 km² ) that would provide nearly 10% of South Korea's total rice production. It is said to be the world's largest wetland reclamation, and the various controversies, court cases and commissions led in part to the Wetland Conservation Act of 1999 (amended 2014), which should both prevent the future loss of wetlands and help with wetland restoration.

History

In 1991 the South Korean government announced that a dyke would be constructed to link three headlands just south of the

South Korea South Korea, officially the Republic of Korea (ROK), is a country in East Asia. It constitutes the southern half of the Korea, Korean Peninsula and borders North Korea along the Korean Demilitarized Zone, with the Yellow Sea to the west and t ...

n industrial port city of Gunsan, south-west of

Seoul Seoul, officially Seoul Special Metropolitan City, is the capital city, capital and largest city of South Korea. The broader Seoul Metropolitan Area, encompassing Seoul, Gyeonggi Province and Incheon, emerged as the world's List of cities b ...

, to create of farmland and a freshwater reservoir. Since then the government has spent nearly 2 trillion won ( billion USD) on construction of the dyke, with another 220 billion won ( million USD) budgeted on strengthening the dyke and a further 1.31 trillion won ( billion USD) to transform the tidal flats into arable land and the reservoir. The average width of the sea wall/earth dam is . It is at its widest, the average height is and it is at its highest. The construction of the Saemangeum Seawall caused controversy from the moment it was announced as environmental groups protested against the impact of the dyke on the local environment.

Supreme Court In most legal jurisdictions, a supreme court, also known as a court of last resort, apex court, high (or final) court of appeal, and court of final appeal, is the highest court within the hierarchy of courts. Broadly speaking, the decisions of ...

challenges in 1999 and 2005 led to temporary production stoppages but ultimately failed to stop the project. Major construction was completed in April 2006, with the seawall longer than the

Afsluitdijk The Afsluitdijk (; ; "closure dyke") is a major dam and causeway in the Netherlands. It was constructed between 1927 and 1932 and runs from Den Oever in North Holland province to the village of Zurich, Friesland, Zurich in Friesland province, o ...

in the IJsselmeer, the

Netherlands , Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...

, previously the longest seawall-dyke in the world. With remaining minor construction and inspection finished, the seawall was officially opened to the public on 27 April 2010. Then South Korean president Lee Myung Bak commented that Saemangeum would be "the kernel and the gateway of South Korea's west coast industrial belt" and was "another effort by us for low-carbon and green growth, along with the four-rivers project". A ceremony was held in Saemangeum the same day, with cabinet officials, politicians and delegates from other countries. a floating solar PV plant of 2.1 GW capacity was planned using the

coastal reservoir A Coastal reservoir is a type of reservoir to store fresh water in a dammed area of a coastal sea near a river delta. Saemangeum Seawall, Saemanguem in South Korea, Marina Barrage in Singapore, Qingcaosha in China, Plover Cove Reservoir, Plover C ...

area of the Saemangeum Seawall.

Composition

The road on Saemangeum Seawall, with a length of 33 km, connects Buan County to Gunsan and is a part of National Route 77. IS: Intersection, IC: Interchange

Environmental Impact

The

enclosure Enclosure or inclosure is a term, used in English landownership, that refers to the appropriation of "waste" or "common land", enclosing it, and by doing so depriving commoners of their traditional rights of access and usage. Agreements to enc ...

of the estuary and its bay by the dyke has had major environmental impacts. It has destroyed 401 square kilometres of mudflats, which many thousands of migratory shore birds using the East Asian- Australasian Flyway once used as a stopover site before continuing their migration south to

Australasia Australasia is a subregion of Oceania, comprising Australia, New Zealand (overlapping with Polynesia), and sometimes including New Guinea and surrounding islands (overlapping with Melanesia). The term is used in a number of different context ...

, and thus is a factor in the major decline of birds such as the Far Eastern Curlew. The dyke has changed both the estuarine tidal system inside the dyke and the coastal marine environment outside the dyke. Following completion of the dyke, red tides, hypoxia and coastal erosion/deposition have occurred successively. Red tides occur almost year round inside the dyke, and even when the sluice gates are fully open the water quality does not improve much owing to the loss of hydrodynamic stirring power. A study of benthic communities enclosed by the dyke and the environmental factors determining them (where the abundance and biomass of various species of intertidal fauna were measured in 2005) aimed at giving baseline data on the "distribution of benthic macrofauna for future monitoring" and at "identifying the relative importance of environmental variables that explain faunal zonation". This study also hoped to give a basis for wetland restoration. Later studies have documented environmental changes together with benthic faunal changes and concluded that tidal damping has greatly decreased benthic fauna species number and density, that the

halophyte A halophyte is a salt-tolerant plant that grows in soil or waters of high salinity, coming into contact with saline water through its roots or by salt spray, such as in saline semi-deserts, mangrove swamps, marshes and sloughs, and seashores. ...

community has been greatly affected, that the shellfish catch has been reduced and that there have been increases in organophosphorus and organochloride pesticides in both seawater and sediments, changes in shorebird populations and massive erosion near the dyke openings. The Saemangeum project is considered to be perhaps the worst example of a massive tidal land reclamation project, which "inevitably destroys the natural and productive ecosystem of tidal flats".

In Culture

Decades-long struggle of citizens against the project is portrayed by Hwang Yin in her 2022 documentary ''Sura: a Love Song''.

References

External links

* "Saemangum seawall completed", ''

The Korea Herald ''The Korea Herald'' () is a South Korean English-language daily newspaper founded in August 1953 and published in Seoul. The editorial staff is composed of Korean and international writers and editors, with additional news coverage drawn from i ...