The region encompasses a population exceeding 15 million persons in an area of more than 38,000 square miles. As the designated Metropolitan Planning Organization, the Association of Governments is mandated by the federal government to research and draw up plans for transportation, growth management, hazardous waste management, and air quality.
Additional mandates exist at the state level.
Development of demographic projections plus the integrated land use, housing, employment, transportation programs, measures, and strategies portions of the South Coast Air Quality Management Plan, as well as serving as co-lead agency for air quality planning for the Central Coast and Southeast Desert air basin districts. Responsibility under the federal Clean Air Act for determining conformity to the Air Plan of projects, plans and programs. To function as the authorized regional agency for intergovernmental review of programs proposed for federal financial assistance and direct development activities. Review of environmental impact reports for projects having regional significance for consistency with regional plans. Pursuant to federal water pollution control statutes, the Association functions as the authorized area wide waste treatment management planning agency.