Simulation on connected water level under minimum discharge flow of Tongjiezi-Shawan Power Station in Dadu River Basin

Abstract

Connected water level is an important factor affecting the efficient utilization of water resources in Dadu River Basin. Based on the latest real and measured data, the connected relationship of Tongjiezi-Shawan Power Station in Dadu River Basin under the minimum discharge flow was analyzed by using hydrological and hydrodynamic simulation method, and the corresponding minimum discharge flow guarantee method was proposed. The result show that, under the influence of long-term scouring after reservoir operation, the stage-discharge relation below the Tongjiezi dam shows a right deviation compared with the design stage, and the corresponding water level is relatively low under the same flow. The backwater at the end of Shawan Reservoir has a jacking effect on the water level below Tongjiezi Dam, and the jacking effect is more obvious when the water level of Shawan Reservoir is above 431 m. The latest data shows that Tongjiezi-Shawan has an incomplete connected relationship, with a connected water level of 430.47 m, which is 1.53 m lower than the designed connected water level of 432 m. Adopting the new connected water level can improve the efficiency of water resource utilization between upstream and downstream cascades while meeting the minimum discharge demand.

Keywords

backwater effect / minimum discharge flow / connected water level / Dadu River