In 1998, the Washington State Department of Transportation (WSDOT) Environmental Affairs Office delineated the Source Water Protection Area (contributing watershed area) for surface water intakes State-wide. WSDOT is now redelineating these watersheds using improved (GPS) locational information, along with improved watershed delineation tools obtained at the 1998 conference. A comparison will be made between the original and most recent delineation efforts. Using motor vehicle accident location data, WSDOT will notify purveyors of surface water systems that have contributing watersheds that are vulnerable to hazardous waste spills. WSDOT will use this information to prioritize highway safety improvements.