运用水电站长渠道引水水力瞬变过程计算方程，分析计算了白龙江横丹水电站长引水渠道各种工况下的运行情况。在计算正常运行工况的基础上，重点研究了在机组增、甩负荷时，瞬变运行状况下的非恒定流运动。对工程是否采用溢流侧堰，进行了对比计算，得到了最危险工况下的前池最高及最低水位，建议工程采用降低引水渠底高程0.5m，取消侧堰工程的方案。

Utilizing the computational equation of hydraulic transient flow in a long channel of water division of a hydropower station, the paper analyzes and computes all kinds of working conditions of water diversion channel of Hengdan Hydropower Station on Bailong River in Gansu province, and on the basis of the computed results under normal condition, emphatically studies the unsteady transient flow when hydraulic turbine set increases or decreases load. The results of two calculation programs with an overflow side weir and without it are compared, by whcih the highest water level and the lowest water level under the most dangerous conditions are obtained. A suggestion that the canal bottom elevation should be decreased by 0.5 m and the overflow side weir taken off is proposed.