Environmental Decision-making

South Coast Air Quality Management District

The South Coast Air Quality Management District (SCAQMD), formed in 1976, is the local governmental agency in California which is responsible for regulating stationary sources of air pollution in the area depicted on the adjacent map. That area includes all of Orange county and the urban portions of Los Angeles, Riverside and San Bernardino counties. The main office of the SCAQMD is located in the city of Diamond Bar, California.[1]

The area encompassed by the SCAQMD amounts to about 10,750 square miles (27,840 square kilometres) and is the second most populated area in the United States. This area has a severe problem with smog and the SCAQMD has been a leader in the nation's efforts to reduce air pollution emissions.

How the SCAQMD operates

The SCAQMD develops, adopts and implements an "Air Quality Management Plan" for bringing the area into compliance with the clean air standards established by national and state governmental legislation.

Air quality and permissible air pollutant emission "rules" are promulgated to reduce emissions from various sources, including specific types of equipment, industrial processes, paints, solvents and certain consumer products. Permits to operate (in compliance with the air quality and emission rules) are issued to the pertinent industries and businesses and SCAQMD staff conducts periodic inspections to ensure such compliance.

The SCAQMD's rules apply to businesses ranging from large petroleum refineries and power plants to gasoline fueling stations and dry cleaning plants. There are about 30,000 such businesses operating under SCAQMD permits. In general, the SCAQMD is limited to establishing rules for regulating stationary sources. Emission standards for mobile sources (automobiles, trucks, buses, railroads, airplanes and marine vessels) are established the U.S. Environmental Protection Agency and the California Air Resources Board.

How the SCAQMD is organized

The SCAQMD has a "Governing Board" of 12 members. Nine of the board members are members of the local county and city governments. The remaining three are appointed by California state officials. The chief "Executive Officer" of the SCAQMD reports to the Governing Board and the following departments report to the Executive Officer:[2]

Administrative departments

  • Policy advisor
  • Legal (Counsel and Prosecutor)
  • Public Affairs
  • Media Relations
  • Finance
  • Human Resources
  • Information Management

Operational departments

  • Engineering and Compliance
  • Planning, Rule Development and Area Sources
  • Science and Technology advancement

Air quality monitoring network

The SCAQMD also operates an extensive network of air quality monitoring stations (about 40 stations) and issues daily air quality forecasts. The forecasts are made available to the public through newspapers, television, radio, faxed messages to schools, the SCAQMD's internet website, and a toll-free smog update telephone line.[3]

Oversight of air quality and air pollution dispersion modeling

The air quality modeling activities of the SCAQMD are one of the functions of the Planning, Rule Development and Area Sources department. That section is also responsible for oversight and commenting upon air pollution dispersion modeling[4][5] studies performed as part of any environmental impact studies that may be reviewed by or requested by the SCAQMD. The models that may be utilized include:[6]

  • California Line Source Dispersion model (CALINE-4)
  • Industrial Source Complex Short Term model (ISCT3)
  • Roadway Construction Emissions Model
  • U.S. Environmental Protection Agency's air quality models
  • California Air Resources Board's air quality models
  • Hotspots Analysis and Reporting Program (HARP)

Funding for the SCAQMD

About 70% of the SCAQMD’s funding is derived from fees paid by the regulated businesses, 20% from motor vehicle registration fees and the balance from other sources such as fines and other penalties assessed for businesses that violate the SCAQMD's rules.


  1. SCAQMD website home page
  2. The SCAQMD's Governing Board
  3. The SCAQMD's Air Quality Monitoring and Forecast Map
  4. M.R. Beychok (2005), Fundamentals of Stack Gas Dispersion, 4th Edition, ISBN 0-9644588-0-2.
  5. D.B. Turner (1994), Workbook of Atmospheric Dispersion Estimates, 2nd Edition, CRC Press, ISBN 1-56670-023-X.
  6. The SCAQMD's Air Quality Modeling

This article was reviewed and approved by Topic Editor C. Michael Hogan



Beychok, M. (2013). South Coast Air Quality Management District. Retrieved from http://www.eoearth.org/view/article/51cbf2aa7896bb431f6aa459