Hydropower development and its negative effects on water quality: a case study in Maotiao River Basin

摘要

Maotiao River Basin is a typical case of rivers' cascade hydropower development in China. In a period of time, the hydropower development provided enough electricity and clean water for local area. While after hydro station operating 30 years, the water quality in Maotiao River Basin was deteriorating, this resulted in the loss of providing clean freshwater's function. The paper mainly analyzes the trend of water quality in Maotiao River Basin, its mechanism, and provides scientific direction for the hydropower development in the near future. Results show that (1) extensive human activities in the upper reaches, involving an increasing number of population, the improvement of urbanization, and the extension of industrialization, are the primary causes of the water quality deterioration. (2) The discharge of sewage of rural residents and urban residents, and the growing use of chemical fertilizer are the direct causes for the water quality deterioration. (3) Among the three major causes, the discharge of sewage of rural residents and the growing use of chemical fertilizer are the most significant factors making the water quality deteriorative.