EPA ArcGIS Server for water-related GIS data. This is not a web browser URL, but rather a an ArcGIS server address. Lots of information available from office locations to scaled watersheds for the United States.
Map and Geospatial Hub - ASU Library Map and Geospatial Hub advances the use of geographically-referenced information by expanding access to and support for cartographic resources and geospatial technologies across the ASU community and beyond.
watersgeo.epa.gov/ArcGIS/services/WC/WaterShedsWC : Can be used with ArcGIS Explorer. Under "Add Content," select "Add GIS Services." Go to the WC folder for watershed information.
Custom Topographic Maps
Boyce Arboretum : This is a custom topographic map of the Boyce Arboretum. The contour interval is 40 feet.
KML of Soils Map of Moer Park : Requires the use of a KML viewer such as Google Earth or ArcGIS Explorer. Use the USDA soil survey to match the soil code with the extensive information found in the soil survey available online. (See Subject Resources box above.)
KML of Soils near San Tan Mountain Regional Park : Requires the use of a KML view such as Google Earth or ArcGIS Explorer. Use the online USDA Soil Survey to match the soil symbol code with the very extensive information found in the survey. (See Subject Resources box above.)