Evaluation of stream temperature change with reservoir management in the Nam Ngum Basin.

The Mekong is a large international river and many reservoir construction projects are planned in the tributaries. Such human activity raises or lowers natural stream-water temperature and, unfortunately, change of water temperature is often undesirable. Control of water temperature therefore becomes a prerequisite for maximum utilization of water resources. Reservoirs often provide a means for exercising such controls. In this study, to evaluate artificial effects on the downstream environment, changes in river water temperature by dam construction were estimated. Then, the mitigation effect of adopting surface intake on the dam site was examined.