Downstream effects of reservoirs in areas suffering from water deficiency-the case of hutouo River, China

摘要

The Hutouo giver is located in the semi-arid areas in China. Due to lack of water resources in these areas, changes in flow regime, mainly reduction in runoff downstream from the reservoirs, have been tremendous. As a result of decrease in flow power and sediment load, the post-dam river showed a less change in channel morphology and the change varied reach by reach. Comparatively, the channel shrinkage may contribute to the flood disasters in the lower reaches of the river in recent years. An obvious increase of channel's hydraulic roughness, the main cause for reduction of flood transmission capacity of the channel, is attributed to vegetation encroachment in the channel. The effects of resevoir construction on ground water level and other environmental aspects are also discussed in the paper.