The City of Aurora's Utilities Department is currently using a geographical information system (GIS) to assist in efficiently managing their water supplies, as well as studying ways to reduce water usage through conservation. For the past four years the City of Aurora's Utilities Department has been using a GIS application to query and analyze water usage from a utility billing relational database. Database design and GIS coverage development was initialized in early 1995 and by mid-1996 a working application was completed. Applications for this GIS tool include studies in water conservation, lawn irrigation return flows, water resources planning, targeting water education efforts, analyzing usage patterns by rate class, and monitoring water savings from a voluntary water audit program. Includes 2 references, figures.