Transportation capacity or mobility projects in Washington State generally begin at the city or county level. As the population and economy grow and shift, transportation infrastructure may also need to expand or change to accommodate these changes. The WSDOT works closely with tribes, cities, towns, and counties as well as the Regional Transportation Planning Organizations (RTPOs) and Metropolitan Planning Organizations (MPOs) and others to understand the demands of growth on the state’s transportation system.
Local agencies must also seek to provide infrastructure within their own jurisdictions. Washington’s Transportation Plan summarizes the need for all of these components of the state’s network of roads, streets, bridges, transit, rail, ferries, air, and non-motorized modes of transportation. The WSDOT also prepares plans for the systems it has jurisdiction over: highways, ferries, airports, and other pieces of the network the state owns and operates. They do even more comprehensive planning for the parts of the network in their ownership. The RTPOs/MPOs describe the regional or metropolitan network made up of state, local, or privately owned transportation facilities and services in their regional or metropolitan transportation plans.  In their comprehensive planning and land use decisions, local governments establish their vision for managing growth and the needed infrastructure to support it. These agencies establish development regulations that specify the level of service they desire for the streets and roads, in their vicinity. The WSDOT uses this information in developing its route or corridor plans. These plans identify the improvements or preservation projects that will be needed to support the growth of the area. These plans may address applicable design criteria, access management, and any design deviations applicable to a given route or route segment. This information of projected need, in turn, is compiled in WSDOT’s 20-year Washington Transportation Plan (WTP) and the Highway System Plan (HSP).  Depending on the funding available from the Legislature, the WSDOT prioritizes the most needed projects. This means that improvement and preservation projects on state routes compete for funding within their project type subcategories on a benefit/cost basis. This ensures to taxpayers that the projects with the “highest benefit to users per dollar spent” will be built first. An example of the Olympic Region’s project list is shown on page 7. The projects get scoped to determine the appropriate design and cost and are then funded as the financial resources become available.  The Growth Management Act (GMA) requires that RTPOs certify that the transportation element of comprehensive plans adopted by counties, cities, and towns reflect approved RTPO transportation guidelines and principles. Both MPOs and RTPOs update regional transportation improvement programs (RTIP) at least once every two years. The updated RTIPs constitute the State Transportation
Improvement Program (STIP):
* Projects that originated in local MPO/RTPO Transportation Plans,
* Projects that are federally funded, and
* All WSDOT and regionally significant projects regardless of funding source.