The present paper describes a computer-based system for water supply project appraisal called EVAPRO, standing for EVAluation of water PROjects. The aim of EVAPRO is to facilitate economic and financial assessment of water supply projects under different investment and operating scenarios, and changes to initial system configuration. The software consists of automating the feasibility study of water projects using information about population and water demand forecasts, potential water resources, investment decisions, financial resources and water pricing policy. It embodies a set of tools, including linear programming techniques, numerical methods and financial calculations, and combines operational optimization with financial analysis to assess the feasibility of water supply projects.The software is intended for water production and distribution agencies and aims to assist engineers and decision-makers in water supply project evaluation and feasibility assessment.