Evaluation of the Performance of a Discharge Gauging Station on Tigris River in Baiji, Iraq

Abstract

Gauging the discharge of the Tigris River in Baiji is very important, as it reflects the final accumulated flows from Mosul Dam, upper and lower Zab tributaries, which send downstream to the control system in Samarra. The current study aimed to evaluate the performance of the Baiji gauging station for measuring water levels and discharge, and thus suggest alternative locations. Large disagreement was found between the manually measured discharge, and that measured by the Acoustic Doppler Current Profiler and in comparison with the discharge coming from the stations of Shirqat and Al-Dibs upstream Baiji, or those discharges sent to Tikrit downstream the station. A topographical survey of the flow section was done to determine the area using manual and Acoustic Doppler Current Profiler techniques for the original and alternative locations. Then flow velocity was measured, then the discharge was calculated according to the flow section area, and the average flow velocity for different levels, the stage-discharge equation was deduced and compared with the other equations used previously. The study concluded that the original station is inefficient, and it is better to move it to the second alternative site, by comparing the three stations, we found that the most accurate measurements were at the second alternative station.