The STA was created in 1990 through a Joint Powers Agreement between the cities of Benicia, Dixon, Fairfield, Rio Vista, Suisun City, Vacaville, Vallejo and the County of Solano to serve as the Congestion Management Agency for Solano. As the Congestion Management Agency for the Solano area, the STA partners with various transportation and planning agencies, such as the Metropolitan Transportation Commission and Caltrans District 4.