We streamlined and clarified rule in August 1997, based on extensive discussions with state and local air pollution officials, transportation planners, and other stakeholders, as well as the experience of both DOT and EPA employees in the field. To date, we believe conformity has been successful in preventing transportation planning decisions from contributing to new violations. Conformity works by reinforcing a state's air quality plan and keeping areas on track in meeting their air quality goals. A state's air quality plan establishes emissions ceilings or budgets for the various types of sources that make air pollution. Conformity makes state and local agencies accountable for keeping an area's total motor vehicle emissions within the budgets established by the air quality plan.
Communities have choices about how to address their transportation and air quality needs.
An area can choose to build transportation projects that increase emissions, as long as the net effect of the total system is consistent with the state air plan. Most areas have been able to continue adding to their transportation network and still stay within their clean air budgets. In several areas, conformity has been at the core of discussions surrounding growth, congestion, air quality, and quality of life. In Atlanta, Georgia, one of the fastest growing areas in the country, the impacts of growth have been front and center for everyone from residents to employers to the Governor's office. Since 1996, the Atlanta Journal-Constitution has been featuring editorials and front page articles about conformity, traffic, air quality, and growth.