In the U.S. state of California, a congestion management agency (abbreviated CMA) is a county-level government agency responsible for a comprehensive transportation improvement program that reduces traffic congestion and reduces transportation-related air pollution through local land-use planning.
Under the California State Legislature to implement Proposition 111 (also known as the Traffic Congestion Relief and Spending Limitation Act of 1990), each county with 50,000 or more residents – in other words, any county required to have a metropolitan planning organization under federal law – must also designate a local government agency to develop a congestion management program (CMP) or forfeit its share of state gasoline tax revenues. In 1996, Assembly Bill 2419 allowed counties to opt out of the CMP requirement by implementing an alternative mechanism for congestion management[1][2] and made the CMP voluntary for counties with fewer than 200,000 residents.[3] San Diego County at one point opted out of the CMP in favor of a regional fee applied to new developments.[1]