용담댐 저수지에 대하여 목표수질 설정과 오염물질 부하량 추정 및 유량분석을 실시하여 수질의 변화과정을 모의함으로써 환경용량과 오염부하삭감량을 추정하였다. 목표수질은 상수원수 $1{sim}2$등급, COD $1.0{sim}3.0$ mg/L와 TP $0.01{sim}0.03$ mg/L로 설정하고, 용담댐 저수지의 수질모형을 42개 소구획을 가진 WASP5로 구성하고, 보정하여 측정치와 계산치의 상관계수는 BOD 0.73, $PO_4-P$ 0.98이었다. 목표수질 COD 2.0 mg/L와 TP 0.02 mg/L에 대한 환경용량은 연구조건에 따라 BOD $131,880{sim}4,694$ kg/일, TP $7,855{sim}167$ kg/일이고, 각 경우의 오염부하 삭감률은 BOD $51{sim}62%$, TP $47{sim}67%$로 나타났다. 환경용량은 기존연구보다 작게 추정되었고 삭감부하율은 기존결과들의 중간에 해당하였다. 상수원수 $1{sim}2$등급의 수질을 연중 달성할 오염부하 삭감률은 기존 연구조건에서 BOD $72{sim}16%$, TP $78{sim}36%$이고, 신규 연구조건에서 BOD $81{sim}44%$, TP $84{sim}52%$로 나타났다. 기존연구의 삭감량과 비교하면 BOD는 가장 적고 TP는 4개 중 2번째로 적었다. 목표삭감부하량의 소유역별 배분에서 TP는 취수탑 구획에 대한 근접도의 영향이 크게 나타났으나 COD는 별다른 차이가 없었다.
The environmental capacity and watershed pollution load reduction of Yongdam reservoir were estimated by the simulation of water quality variation process with the target water quality establishment, pollution load estimation and flow analysis. The potable raw water $I{sim}II$, COD $1.0{sim}3.0$ mg/L and TP $0.01{sim}0.03$ mg/L were selected as the target water quality Yongdam reservoir water quality model was constructed with WASP5 contained 42 segments and the correlation of calibrated results were BOD 0.73, $PO_4-P$ 0.98. The environmental capacity for target quality COD 2.0 mg/L and TP 0.02 mg/L were BOD $131,880{sim}4,694$ kg/d, TP $7,855 {sim}167$ kg/d which were less than exists, and the related reduction ratios were BOD $51{sim}62%$, TP $47{sim}67%$ which were middle amount in exists. The load reduction ratios to meet the potable raw water $I{sim}II$ were BOD $72{sim}16%$, TP $78{sim}36%$ in existing conditions and BOD $81{sim}44%$, TP $84{sim}52%$ in new conditions. BOD was the least one and TP was the second least in 4 results. The effects of the load reduction assignment to subbasin were dominant in TP but little in COD.
