This research presents a modeling and optimizing alternative for water reservoirs placement of an Urban Water Supply Systems (UWSS). These systems are considered as decision making support systems for planning. The focus is the advances and techniques found in the Geographical Information Systems (GIS) and the possibility to use it as Spatial Decision Support System (SDSS). This research presents a new methodology for decision making in a planning of UWSS. Risk Maps are produced using multi-criteria evaluation techniques for urban parcels. They can indicate some planning and management actions. It is established a suitability zoning to locate new water reservoirs units, which can support guidelines and planning for expansion of system
geotechnologies; water supply systems; spatial decision support system
