영산강 수질개선효과를 위한 홍수조절지의 활용기회분석

Abstract

Most of the water quality of the Yeongsan river is below the average water quality, and the worst water quality compared to the four major rivers has limitations in terms of water use. The need to improve water quality has been continuously raised as it is vulnerable to water quality management due to excessive discharge water from sewage treatment plants, which is three to four times the direct upstream instream flow rate. Two Damyang and Hwasun reservoirs have been completed and operated on the Yeongsan river as part of the four major river projects. The detention reservoir is a reservoir to reduce the amount of downstream flooding by storing part of the flood. However, the Yeongsan river needs to secure water to improve water quality by using detention reservoir. In order to secure the quantity, the precipitation (2012~2019) was investigated and the average precipitation in the basin was calculated by Thiessen method to analyze the number of times the detention reservoir precipitation is more than 20mm. As a result of the analysis of the non-flood season, Damyang detention reservoir was analyzed that the amount of precipitation of more than 20mm occurred 58 times over 7.5 years, which could be utilized 7.7 times a year. It was analyzed that Hwasun detention reservoir occurred 54 times in total and could be utilized 7.2 times a year. Excluding the flood season to be used for flood control purposes, the opportunity to use Damyang and Hwasun detention reservoir to improve the water quality of the Yeongsan river was analyzed about 7 times a year.