Seomjingang dam, the first multipurpose dam completed in 1965 in Korea is a concrete gravity dam with 64 meters in height, 344 meters in length, and 40,000ton in concrete volume.

One of the two hydropower plants which was constructed as the first hydropower plants in Korea, is still in operation with the installed capacity of 34.8MW.

The Seomjin river, one of the five largest rivers in Korea, has 4,897㎢ of drainage area with 226km river length, and it finds its way to the southern sea, meandering through southren part of the country. Upstream region of the dam has the annual average precipitation of 1,253 mm that is relatively abundant compared with the other region of the country.

At the time when the energy and water supply were short in 1960's, the dam has contributed to the electrical energy supply in this region as well as to the irrigation of Kimje plain with sufficient water diverted to the Tongjin river. It also has reduced flood damage in the downstream region of the dam.