Statewide GIS maps & data layers

Online Map Center

The WSDOT Online Map Center provides instant access to a wide variety of data driven map content including interactive map applications, geospatial data layers and printable maps in PDF format.

GIS data download

• Use the WSDOT Geospatial Open Data Portal to explore, filter, and download WSDOT spatial data and access interactive and printable maps.
• For all Washington State Agency GIS Open Data content see the Washington State Geospatial Open Data Portal.

Other featured map applications

• Use the Locate Milepost application to quickly identify or locate mileposts along our state highways.  This simple and intuitive interface allows users to input state route and milepost values and be zoomed to that location, or to click on a highway to learn the milepost at that location. This is a WSDOT supported tool with a simple interface and targeted functionality to provide an intuitive experience for users, internal or external to WSDOT. This tool replaces the Snagmp tool that is no longer supported.
• GeoPortal - view WSDOT spatial data (like functional class, interchange drawings, city limits and state routes) via a web browser. Users can check a box to select from a variety of base maps and data layers. Users can also click on the map to return a State Route Mile Post number or type an address to zoom to. The GeoPortal Help and Users Guide (PDF 2.4 MB) can assist you in learning how to use the application.
• Survey Monument Database (under Tools, templates & links tab) - use this interactive web page and map application for locating geodetic control monuments. With this application you can view and query WSDOT survey monuments, National Geodetic Survey (NGS) stations, Washington state route mileposts and Washington county boundaries on top of a topographic base map. Use the Monument Mapping Engine User Guide (PDF 3.53 MB) to learn how to use the application. Feedback and data questions should be sent to: monument@wsdot.wa.gov
• Interchange Viewer - view and print drawings of state highway interchange areas, couplets and other select locations in PDF format. While not drawn to scale, these drawings can be used to help locate collisions more accurately, to identify specific ramps and to assist in other planning purposes. The interchange drawings are updated through state highway construction contracts, subsequent on-site inspections and input from WSDOT staff.