GB 17621-1998

This standard specifies the technical requirements for reservoir operation scheduling, including water level control, flood management, and power generation coordination, specifically for large and medium-scale hydropower stations in China. It is applied by hydropower plant operators and grid dispatch centers to ensure safe, efficient, and economical utilization of water resources while balancing flood control, irrigation, and ecological flow demands. The standard is mandatory for all newly built and existing hydropower stations with a reservoir capacity above a certain threshold, guiding daily operational decisions and long-term planning.