남강 중권역의 효율적인 유역관리를 위한 중점관리 대상지류 선정

The major 24 tributaries in Nam-River mid-watershed were monitored for discharge and water quality in order to understand the characteristics of the watershed and to select the tributary catchment for improving water quality. According to the analytical results of discharge and water quality monitoring data of 24 tributaries, the mean value of discharge below 0.1 m3/s was 62.5% among the monitored tributaries and it mostly exceeded the water quality standards of Nam-river mid-watershed (BOD5 = 3 mg/L, T-P = 0.1 mg/L over). According to the stream grouping method and the water quality delivery load density (kg/day/km2) based on the results of tributary discharge and water quality monitoring, the tributary watersheds for improving the water quality were selected. In the Nam-River mid-watershed, tributaries in the GaJwaCheon, HaChonCheon catchment (Group D, BOD5 = 3 mg/L over) and in the UirYeongCheon, SeokGyoCheon catchment (Group A, T-P = 0.1 mg/L over), which have a small flow (and/or large flow) and a high concentrations of water pollutants. The various water quality improving scheme for tributaries, in accordance with the reduction of potential point source pollution by living sewage and livestock wastewater, should be established and implemented.