An integrated indicator based on basin hydrology, environment, life, and policy: The watershed sustainability index

Several issues impact the water sustainability of a river basin. Among them are the social, economic, and environmental aspects. However, they are often treated separately, and not as an integrated, dynamic process. In order to integrate the hydrologic, environmental, life and policy issues, as well as the existing pressures and policy responses in one quantitative, dynamic, and aggregated indicator, a watershed sustainability index (WSI), which uses a pressure-state-response function, was developed and is proposed in this paper. Applied to a 2,200 km(2) Unesco-HELP demonstration basin in Brazil (SF Verdadeiro), the value obtained for WSI was 0.65, which represents an intermediate level of basin sustainability.