Estimation of Reservoir Discharge to Support TMDL Management in the Geum River Basin

This study estimates adequate discharge to meet the specified target water quality concentration using the pollutant load of the Geum river basin given in TMDL (Total Maximum Daily Load) report. During the 1st phase, BOD is chosen as a target water quality constituent under regulation of the Ministry of Environment in Korea. BOD, TN, and TP loads estimated based on the TMDL and provincial zones were re-distributed for 10 major tributaries, and the remaining areas along the main river are classified as 15 incremental flow areas. Water quality modeling was conducted using Qual2E for the low flow period of a year (i.e. ). The results of the model simulation showed that about 30 cms from the Daechung dam would be sufficient to satisfy the target water quality in the Geum river downstream of the Daechung multipurpose Dam.