Estimation of River Discharge Using Adcp in an Estuary

Abstract

正会員 (株)福田水文センター 調査部(〒001-0024 札幌市北区北24条西15丁目)2 正会員 工博 ユニヴ・テック 環境流体研究所 所長(〒001-0030 札幌市北区北30条西13丁目) 3 北海道開発局 石狩川開発建設部(〒060-8541 札幌市中央区北2条西19丁目)Discharge can be considered one of the most essential hydraulic parameters to know about a river for managing it. Ordinarily, the H-Q equation is used to estimate the discharge from the level of a river. Certainly, this provides acceptably accurate estimates in the upper reaches of rivers. In estuaries, however, its accuracy is fatally degraded. In the initial part of this study, a river was divided into 15 zones in the traverse direction, and the discharge in each zone was compared with the actual discharge of the river itself to see what kind of cross section allowed the local discharge to show the best correlation with the river discharge. Then, ADCP were placed on the riverbed and longterm measurements of the flow speed distribution were taken for comparison with the discharge as indicated by actual measurements. A clear proportional relationship was obtained between the two sets of data. It is clear that the equation relating the data sets provides a far superior estimate of discharge over the H-Q equation.