Development of the Annual Runoff Estimation Model

연유출량 추정모형 개발

The study was focused on developing a new model to estimate annual runoff. This model can be used to estimate the available water resources for ungaged catchments for long-term water resources development planning. Data used in the model development were daily rainfall and daily runoff of the sample basin with record length from 1945 to 1988 years in Korea. The sample basin selected by consideration whether the flow is virgin and quality of discharge data is good. As a result, 46 stage gaging station were selected. Annual runoff was determined by sum of daily runoff calculated by daily stage data of the sample basin. Also, the annual mean precipitation by using daily rainfall data was estimated and the annual runoff ratio for each sample basin was calculated, and the annual mean runoff ratio was estimated. The linear regression model was proposed and calibrated using auunal mean precipitation values and geomorphological characteristics of the basins. To verify reasonableness of this model, the regression model was applied to the gaging stations which have historical data.

본 연구에서는 장기 수자원계획시 유역내 가용 수자원을 파악하는데 이용할 수 있는 새로운 연유출량 추정모형의 개발을 시도하였다. 연구범위는 우리나라 전역으로 1945년부터 1988년 까지의 육수량, 유출량 자료를 이용하였다. 모형개발을 위한 표준유역은 유출의 인공조작이 없고 수위자료가 양호하며, 수위-유량 관계곡선이 작성되어 있는 46개 지점을 택하였으며, 표본 유역별로 일수위 자료를 수집, 정리하여 일유출량을 산정하고 합산하여 연유출량을 산정하였다. 또한, 연평균강수량을 산정하여 지점별로 연유출율을 계산하고 이것을 기초로 우리나라 연평균 유출율을 추정하였다. 그리고, 연유출량과 역특성인자들을 이용하여 연유출량 추정모형을 개발하였으며, 실제유역에 적용하여 모형의 합리성을 검토하였다.