This paper presents the construction of a Web site whose goal is allowing users to access, update, and print source water contaminant inventory data through a standard Web browser and Internet connection. It allows users with a very limited knowledge of GIS operations to view ArcView GIS themes using Internet Map Server, make useful customized queries of the data, and produce quality cartographic products for their own use. It also allows qualified users to make changes to ArcView GIS themes or underlying databases.