The Washington Constitution provides that public funds may be expended only by appropriation. Such appropriations are provided in a biennial omnibus transportation budget (budget) adopted by the Legislature in odd-numbered years. The budget provides appropriations to the major transportation agencies including: the Washington State Department of Transportation, the Washington State Patrol, the Department of Licensing, the Washington Traffic Safety Commission, the Transportation Improvement Board, the County Road Administration Board, and the Freight Mobility Strategic Investment Board. The budget also provides appropriations out of transportation funds to many smaller agencies with transportation functions. Alternatively, the Legislature may also appropriate state funds through a stand-alone bill.
The bill contains a blanket provision specifying that additive transportation funding is adopted for the 2021-23 fiscal biennium.