Abstract: Water footprint (WF), an index of water consumption by a product, could help evaluate the environmental costs of a hydropower station more accurately. Based on the lifecycle assessment (LCA), we calculate the gross WF and the net WF of Xiluodu hydropower station, considering both construction phase and operation phase. The calculation gives a gross WF of 0.56 m3/GJ and a net WF of 0.02m3/GJ. And it shows that the water use in sand aggregate processing makes the largest contribution to the construction WF, the increase of water surface evaporation caused by reservoir construction makes the largest contribution to the net WF, while the largest to the gross WF is water consumption of operation phase. This study also evaluates the influence of lifecycle span on the components of the gross WF and the net WF. The WF values of Xiluodu hydropower station, significantly smaller than those of other hydropower projects all over the world or other energy industries, show its superiority in water use efficiency as a typical case of the Jinsha River hydropower base.

Key words: reservoir management, Xiluodu hydropower station, water footprint (WF), net water footprint, construction phase, lifecycle assessment (LCA)