The Water Evaluation And Planning System (WEAP) operates on the basic principle of a water balance and can be applied to municipal and agricultural systems, a single watershed or complex transboundary river basin systems. Moreover, WEAP can simulate a broad range of natural and engineered components of these systems, including rainfall runoff, baseflow, and groundwater recharge from precipitation; ... sectoral demand analyses; water conservation; water rights and allocation priorities, reservoir operations; hydropower generation; pollution tracking and water quality; vulnerability assessments; and ecosystem requirements. A financial analysis module also allows the user to investigate cost-benefit comparisons for projects.
WEAP has been succesfully applied in hundreds of organizations around the world including government agencies, utilities, non-profits, academia and consulting organizations. WEAP's key strengths are its flexibility, scenario approach, ease-of-use and powerful data management and reporting tools.