The 18th amendment to the Washington State Constitution dedicates motor fuel tax collections to “highway purposes". Revenue generated from the gas tax is distributed to counties, cities and state accounts. The state receives about half of the total revenues collected. These are the funds which support the WSDOT highway programs as well as the Washington State Ferry System, which is deemed a state highway system by constitution. Highway construction, maintenance, preservation, administration and debt service on highway construction bonds are all funded by these revenues.
The other half of the fuel tax revenues are distributed directly to cities, counties and other agencies for roadway programs that are not part of the state highway system.