南水北调西线对引水河流径流的影响

The influence of western "South-North Water Transmission" project on three rivers' runoff

南水北调西线工程规划总调水170亿m3。其中,从通天河调水80亿m3,雅砻江调水65亿m3,大渡河调水25亿m3,并分三期实施。调水减少了“三江”年径流总量,改变了径流的年内分配,调水对径流的影响上游河段大于下游,汛期大于枯期。

17000 million ms water is to be transmitted to the northern part of China from the upper stream of Yalong，Dadu and Jinsha river in three phases in accordance with the western “South-North Water Transmission” project planning. The implementation of the project will cause some influence on the water resources of these three rivers. It will reduce water discharge, change the monthly run-off distribution. The influence in upper stream is larger than that in down stream. The decrease of runoff in flood season is more serious than dry one。