As the Regional Transportation Planning Organization (RTPO) for Spokane County, SRTC is required by the 1990 Washington State Growth Management Act (GMA) to ensure that local and regional transportation plans coordinate with and are consistent with each other.

As defined in the Revised Code of Washington (RCW), including the GMA, duties of an RTPO include certification that Countywide Planning Policies (CWPP) and the transportation elements of local comprehensive plans are consistent with the regional transportation plan (Horizon 2040), GMA planning requirements, and RCW guidelines and principles related to regional transportation planning. Consistent means that no feature of a plan or regulation is incompatible with any other feature of a plan or regulation.