We maintain 27 bridges, including six on the Willamette River, and over 250 miles of roads. We are responsible for the design, construction, maintenance, operation, and planning for these roads and bridges. We are also home to the County Surveyor’s office.

Bridges | Roads | Survey Office | Transit Services | Transportation Planning and Development

The areas we serve include:

  • West County unincorporated areas, such as Sauvie Island and parts of the West Hills 

  • Six bridges on or near the Willamette River: Sellwood, Hawthorne, Morrison, Burnside, Broadway, Sauvie Island

  • Major streets in Fairview, Wood Village, and Troutdale

  • East County unincorporated areas such as Corbett and Springdale

  • The Surveyor’s office serves the entire county.

We do not serve any roads inside Portland or Gresham.

To find out if a specific road is county-owned, please visit our online map.

Where does our transportation funding come from?

  • State highway fund (primarily provided through state gas tax), state vehicle registration fees and weight mile tax on trucks

  • Multnomah County gas tax, shared with local cities

  • Multnomah County vehicle registration fee, dedicated to our Willamette River bridges

  • Competitive grants

  • No funding comes from property taxes


We manage and maintain six Willamette River bridges and over 20 smaller bridges elsewhere in the county.

We don't maintain any of the Willamette River bridges that carry state or interstate highways or freight trains. Learn more about our Willamette River bridges.


We manage and preserve the county road infrastructure, and provide a safe and efficient transportation system that supports economic and community vitality. 

We don't maintain any roads in the cities of Portland and Gresham. In Fairview, Troutdale and Wood Village, we maintain most of the major roads but no residential streets. Learn more about our roads.

Survey Office

We review and maintain public survey records and make them available to the public, review and approve land divisions, maintain survey monuments, and assist other agencies and the public with our survey  expertise.

Transit Services

Through state funding, the county partners with local governments and agencies to enhance transit options in areas lacking fixed routes.

Transportation Planning and Development

We manage the development of plans to address all modes of transportation at both the local and regional level. We review development plans by others on or near our roads to identify what impacts those plans will have on the transportation system.