Abstract: On the basis of our previous potential analysis, we further probed into the operation rules between different reservoirs and different cascades, gave the joint optimal scheduling diagram, and analyzed the sequences of water impoundment and discharging of involved power stations to improve the utilization efficiency of water resources. Results demonstrate that the release sequence of the reservoirs before flood season should be: Lianghekou-Longpan-Jinping I-Ertan-Xiangjiaba-Baihetan-Xiluodu-Wudongde. The overall water releasing idea is to give priority to the upstream reservoirs and keep the downstream power stations such as Xiluodu and Wudongde operating at high water level as far as possible to improve the overall power generation efficiency of the basin. The order of water storage in the reservoirs at the end of flood season should be: Jinping I-Longpan/Ertan-Lianghekou-Wudongde-Baihetan/Xiluodu-Xiangjiaba. The overall water storage idea is to release the flood control capacity of the upstream reservoirs to start storage on a priority basis so as to alleviate the flood control pressure in the downstream, and the storage in wet years should be delayed accordingly.

Key words: wate resources utilization efficiency, cascades on Yalong River, cascades on middle and lower Jinsha River, joint optimal scheduling rules, scheduling diagram