Local Air Quality

St. Louis Then and Now

A History of Air Quality Concerns

In the late 1800's, St. Louis was a city of growth and rapid development. Industrial growth produced billows of sooty coal smoke that took its toll on St. Louis and the environment. On November 28, 1939 the worst smoke cloud in St. Louis' history enveloped the downtown area. Streetlights had to be turned on at midday, people couldn't see buildings across the street and traffic was delayed. This day became known as Black Tuesday. Public outcry demanded a plan to eliminate the smoke problem. City officials and community leaders worked together with businesses and took action. St. Louis became the first major U.S. city to control urban smoke pollution and to place limitations on the usage of low quality coal.

In the 1960s and 1970s, as suburbanization and auto-dependency accelerated, emissions from personal automobiles became a significant factor in our region's ongoing battle for clean air.

Developed by East-West Gateway Council of Governments
Source: U.S. Bureau of the Census
University of Virginia, Geospatial and Statistical Data Center: Historical Census Browser

1970 ­ National Standards Set for Air Quality

In 1970 Congress passed the Clean Air Act (CAA) which allowed the newly created Environmental Protection Agency (EPA) to set national air quality standards. The same year, St. Louis established the first integrated air quality monitoring network. In 1981 new vehicle emission standards were passed and auto manufacturers placed catalytic converters into all automobiles helping reduce hydrocarbon and carbon monoxide emissions in automobiles by 96% and nitrogen oxides by 75%. Further progress included auto emissions inspection and maintenance programs in 1984 and required Stage II vapor Recovery nozzles on all gasoline pumps in 1989. In 2000, The Gateway Clean Air Program, an enhanced auto emissions inspection and maintenance program, was introduced for the St. Louis City and several surrounding Missouri counties. Today, the Gateway Vehicle Inspection Program (GVIP) serves as the emissions testing and safety inspection program for vehicles registered in the St. Louis ozone nonattainment area, which includes St. Louis City, and Franklin, Jefferson, St. Charles and St. Louis counties.  The Gateway Vehicle Inspection Program tests all 1996 and newer gas-powered vehicles, and 1997 and newer diesel-powered vehicles registered in the ozone nonattainment area. The program serves as a key component of the ongoing effort to improve air quality in the St. Louis area.

Today, Work Continues to Clear our Air

Despite these measures and improvements in our air quality, there is still concern that the ever-increasing use of automobiles will cause continued air quality problems. The average combined daily travel in St. Louis is more than 72 million miles each day and emits more than 88 tons of ozone-forming VOC emissions into our air.

The St. Louis region currently is designated as a non-attainment area for the eight-hour standard for ozone pollution levels. The new eight-hour designation came in April 2004, just months after the region was declared to be in attainment of the one-hour standard. Compliance with the new eight-hour standard will better protect the public's health, but meeting the standard will require renewed commitment by individuals and business throughout the St. Louis region.

Since 1995, The St. Louis Regional Clean Air Partnership, has been the driving force behind the region's voluntary initiatives to clean the air. The organization continues to encourage the use of alternative modes such as transit and carpooling to reduce solo commuting, and also encourages area residents and business to do that they can at home and at work to reduce emissions. As in the past, we believe that working together as a community, we can clean the air.

In 2008, after a lengthy review process, USEPA revised the 1997 eight-hour ozone National Ambient Air Quality Standard to 0.075 ppm (or 75 ppb).

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About Air Pollution Subcategories

Air Pollution Basics
• What is Ozone?
• Sources of Ozone
• Ozone Formation

Air Quality Facts

Health Effects of Ozone
• St. Louis Population with
Lung Disease
• How Healthy Adults are
Affected by Ozone
• Tips for Exercisers
• Ozone & Hospital
Admissions

Particulate Matter

Local Air Quality
• St. Louis Monitor Map

Air Quality Index

Air Quality Data