The history of wastewater treatment in Korea began in 1976 with construction of Chongke sewage treatment plant in the city of Seoul. At present, there are 48 large municipal sewage treatment plants for 42 cities with a total treatment capacity of 7,841,000 m3/d. This indicates that the population receiving sewage treatment is 42% of the total national population. The government is planning to extend the population receiving wastewater treatment to 73% by the year 1997. It turned out that activated sludge processes are the most popular type (39 out of 48 plants) for the treatment of municipal wastewater.
The present lawful effluent criteria for BOD, COD, and SS from large municipal wastewater treatment plant are changing from 30 mg/l, 50 mg/l, and 70 mg/l, to 20 mg/l, 40 mg/l, and 20 mg/l, respectively, by the year 1996. Regulation of the total concentrations of nitrogen and phosphorus are also added as 60 mg/l and 8 mg/l, respectively. The enactment to control the nutrient concentrations in the lake and pond is inevitable for the protection of drinking water in South Korea.