Completed in 1985, Chungju Dam was built to develop water resources in the Namhangang River basin and to supply agricultural, domestic, and industrial water to downstream areas as well as for flood control and hydropower generation. The annual precipitation in the mid and upper regions of Hangang River at that time was around 1,200–1,300 mm with about 60% concentrated in the summer months; thus raising serious concerns about recurring flood damage. In addition, as national economic development plans accelerated in the late 1970s, demand for domestic and industrial water and electricity increased rapidly. To address such imbalance of water resources and challenges in power supply, Chungju Dam was constructed with height of 97.5 m, length of 447 m, and total storage capacity of 2.75 billion m³.
Chungju Dam is the largest multipurpose dam in Korea in terms of basin area (6,648 km²). With its flood control capacity of 620 million tons, it has protected the living areas of 25 million people in the Hangang River basin from major floods, including Typhoon Rusa in 2002 and Typhoon Maemi in 2003. It also supplies 3.38 billion m³ of domestic and industrial water annually, supporting the growth of major inland industrial complexes such as Chungju, Cheongju, Ochang, and Banwol. Moreover, the dam makes substantial contributions to hydropower generation by producing 850 million kWh of clean hydropower annually—enough to cover the electricity demand of approximately 270,000 households. This accounts for about 40% of the total hydropower generation managed by K-water and up to about 25% of Korea’s conventional hydropower. Through these multipurpose functions, Chungju Dam has served as a cornerstone of national economic growth since its completion by providing stable energy essential for Korea’s industrialization and urbanization.