Goheung County Successfully Docks Nation’s Longest Underwater Pipeline

Green Light for Water Supply to Sisan Island in Doyang-eup
Full-Scale Efforts to Resolve Drinking Water Shortages in Island Regions

Goheung County in South Jeolla Province (Governor Gong Youngmin) announced on May 30 that it had successfully completed the docking of the nation’s longest underwater pipeline (4.23 kilometers) as part of the water supply project for Sisan Island in Doyang-eup, which is being carried out as part of a drinking water source development project for island regions.

The ongoing Sisan Island drinking water source development project is a large-scale water supply infrastructure initiative, with a total project cost of 22.7 billion won. The project involves the installation of a 4.23-kilometer underwater pipeline, a 5.37-kilometer land pipeline, and one integrated reservoir.

Plan view of the water supply project in Sisan Island, Doyang-eup, Goheung. Provided by Goheung County

In particular, the docking section of the project has drawn significant attention due to its status as the longest single underwater water supply pipeline in the country, presenting considerable technical challenges.

The successful completion of the docking marks a major milestone in overcoming one of the biggest challenges in the installation of the long-distance pipeline running underwater from Ocheon Village in Geumsan-myeon to Sisan Island in Doyang-eup. This achievement is expected to provide a stable foundation for the project’s continued progress and for the early supply of water.

Sisan Island in Doyang-eup is a remote island community with 135 households, 190 residents, and over 400 full-time seaweed farm workers. The area has long suffered from deteriorating water quality and shortages of domestic water due to groundwater depletion and saltwater intrusion. In response, Goheung County began construction in May of last year to address the long-standing wish of Sisan Island residents for “clean and safe tap water,” and has been steadily pushing the project forward.

A county official stated, “With the successful docking of the underwater pipeline, we will do our utmost to complete the project without delay by 2027 so that island residents can reliably receive clean tap water.” The official added, “We will continue to expand essential infrastructure to improve residents’ quality of life and living conditions.”