The county transportation system encompasses all of the San Juan Islands. It brings people and goods into the community and provides the means by which they can move freely within each island from one activity to another. It works closely with Washington State Department of Transportation, Washington State Ferries, County Road Administration Board and the Town of Friday Harbor.

Public Works produces studies on traffic, vehicle speeds, accident history, engineering improvements, capacity management, marine facilities, pavement ratings, maintenance of roads, and reconstruction of existing services. These studies help us in planning for future transportation needs.

Traffic Studies
San Juan County transportation system monitors traffic volumes, vehicle speeds, and vehicle classification annually. Individual traffic studies are also performed on an as needed basis.

Traffic classifiers, are set in key locations on county roads and records the number of vehicles passing a given location on an average day. San Juan County uses Annual Average Daily Traffic (AADT). AADT is calculated with the following seasonal fluctuation conversion factors established by Washington State Department of Transportation.
  • AADT San Juan County
  • Road Maps
  • 85th Speed Percentile
Please visit GIS Map Gallery for maps

Non-Motorized Transportation
Public Works will implement approved transportation-based projects on a priority basis and assist in the coordination with other agencies and acquisition of funds from other sources to address projects important to the communities but outside the scope of the department.

Current Projects
  • sjRideshare
  • San Juan Trails Committee
  • Orcas Pathways
  • SJC Noxious Weed Board
  • National Scenic Byways
Marine Facilities
San Juan County currently owns and maintains 8 docks with floats, 8 boat ramps (3 barge capable) and lease two outer island moorage docks. Continuing maintenance includes replanking and replacing piles, abutments and braces as needed.

During winter months Madrona Point, Eastsound, Orcas Island marine facility will be closed November 1st - April 1st.

San Juan County Public Works - Engineering Division