악근천 유역의 기저유출량 산정

Abstract

Based on precise observation on Akgeun Stream in Jeju Province maintained by spring water with a two-week interval using up-to-date measuring device, baseflow discharge was calculated with Weir flow equation from water level measurement for comparative analysis. Daily average discharge of the subject stream observed by ADCP was 68,083m3, and observation by Flowmate and ADC was 56,765m3. Flow discharge was large at 0.748~1.541 during summer but was significantly reduced during winter to 0.226~0.614. Discharge during summer was about 3.37 times that during winter. Reason for smaller observation value by Flowmate and ADC compared to ADCP is probably because of error in average flow caused by observation distance, horizontal flow distribution, and perpendicular flow. Average daily discharge computed using broad-crested Weir equation was 94,797m3 with RMS error of 0.478. For a more precise calculation of stream baseflow discharge, long-term observation and theoretical study are necessary.