Drought-waterlog encounter probability research between the diversion region and benefited region in the Middle Route of South-to-North Water Transfer Project

One of the major risk factors in managing water resources in the South to North Water Transfer Project will be due to spatial and temporal variations in precipitation. This is because the synchronous encounter probability of drought and waterlog can be different at the diversion region and benefited region. This study analyzed the statistical characteristic of drought and waterlog in the diversion region and benefited region and the wetness-dryness encountering probability among the diversion region and benefited region. Besides, the wetness-dryness encountering probability and the surface water resource in the diversion region were also projected based on the outputs of GCMs. The results showed that: (1) The concurrence of drought or waterlog in diversion region and benefited region is uncommon and it benefits the water transfer. (2) In the future, the synchrony of drought/waterlog will increase in wet season while it will decrease in dry season. But the synchrony of drought/waterlog between the north of Haihe River Basin and diversion region will decrease in the late spring, early summer and autumn. (3) The surface water resource is projected to be increased by 8.1∼11.5% compared to the period from 1961 to 2011. The climate change in the future would benefit the water transfer.