Geographic Information System Program

Tuolumne County has had a Geographic Information System (GIS) program for over 20 years and provides GIS services to a variety of functions within Tuolumne County government as well as the public.

Originally designed as a tool for use in planning, the GIS program is now in use by Public Works, the Assessor's Office, and the Elections Office. A particularly significant user of GIS data is the Sheriff's Department, which employs data maintained by GIS for dispatch, investigations, and search and rescue. In addition, hundreds of companies, organizations, and individuals outside of the government download and use Tuolumne County data routinely at no cost.

Online GIS Maps and Tools 

NEW Web Maps:
The old "Flex Viewer" and Javascript maps have been retired and replaced with new web mapping applications. Check out our new web maps by clicking on the images below. Each map includes basic instructions in the left side bar. If you experience any problems or need further instruction, use the Contact Us information on this page. 

For best results use Chrome. Internet Explorer will load these maps, but some tools will not function properly.

Link to Fire Incident Information Map, including evacuation areas

Image of fire evacuation map. Image links to interactive web map.

Road Closure Map - Includes hard and soft road closures, chain control locations, traffic incidents, and more

Tuolumne County Road Closure Application

Zoning, land use & building snow load requirement lookup map

land use lookup thumb

Supervisor District lookup map

Link to interactive Supervisors Map

Find your school district


TUD Electoral Districts

Tuolumne Utilities District Board of Directors Map image and link to web map

Current Power Outages

If there's something specific you'd like to see please let us know! Use the contact us email link in the upper right or find us in the staff directory - we are listed under Public Works. 

GIS Data Downloads

The most requested GIS files the County maintains are available for download by users who have GIS software that would allow them to load and view those files. Users are asked to read a disclaimer statement and provide some basic information via the File Access Request Form. Upon completion of that process, users will be notified of the path to the GIS file list page where they can download zipped folders containing shapefiles. Once you have that path address, you can keep that as a favorite on your browser and return there regularly. We hope to update the shapefile packages of the regularly maintained files (roads, parcels, General Plan) frequently, the others as needed.

Data Sets

The two primary data sets maintained by Tuolumne County are the cadastral parcel layer and the road center line files. Attributes for parcels include zoning, and related layers include the general plan land use designations, supervisor districts, school districts, voting precincts, and other special districts such as fire prevention, water, and other utilities. The road files include official road names and address ranges and are used by the Transportation and Engineering divisions.