Air quality still improving, DNR report shows

Wisconsin State Farmer

Madison - Concentrations of fine particles and other air pollutants in Wisconsin continue to improve - that is the latest message coming from the most recent data in the Wisconsin Department of Natural Resources Air Quality Trends Report.

The December 2016 report provides official state monitoring data through 2015 for air pollutants and shows trends in Wisconsin's air quality over time. In general, concentrations of most pollutants regulated under the Clean Air Act have been decreasing over the past decade in all regions of the state.

Wisconsin Department of Natural Resources

One of the many success stories highlighted in the report is the significant reduction in fine particle pollution. Fine particles form when air pollutants react in the atmosphere with ammonia and other gases. Fine particles may also be emitted directly from high temperature combustion sources such as vehicles, fires, or large boilers.

The trends report demonstrates how successful regulatory controls have been in reducing concentrations of this pollutant. Statewide, ambient concentrations of fine particles have decreased by approximately 30 percent over the last decade.

The report shows a clear correlation between the start of this reduction and when new automobile fuel standards (regulations that removed sulfur - a fine particle precursor - from fuels used in automobiles) were implemented in 2007.

Other state and federal regulations controlling the emissions of sulfur dioxide and nitrogen oxides from power plants are also responsible for these reductions. In Wisconsin, these reductions were so pronounced that three counties in Southeastern Wisconsin, which were not previously meeting the 24-hour fine particle standard, were able to be redesignated to attainment in 2014.

All counties in Wisconsin now monitor concentrations of fine particles well below the federal air quality standards and are considered to be "in attainment" by U.S. Environmental Protection Agency.

The report reinforces the importance of operating a well-functioning statewide air program and air monitoring network, providing valuable information to understand Wisconsin's long-term trends in air quality. In tune with current alignment efforts, the DNR air program has and will continue to implement innovative approaches and efficiencies to address core priorities.

Some of the report's other key findings include:

  • Monitored pollutant levels continue to decrease statewide;
  • The number of Wisconsin counties not meeting federal air quality standards remained at its lowest number since the enactment of the 1990 Clean Air Act amendments;
  • The long term trend of overall improved air quality in Wisconsin has been occurring for decades.

"These trends demonstrate that Wisconsin's Air Program has been very successful in implementing regulatory approaches that are enhancing the state's air quality," said DNR Air Program Director Gail Good "Wisconsin's Air Program is a national leader in implementing strategies to improve air quality. Even though the air is much cleaner, the public may see information that suggests just the opposite. By providing real time monitoring data and information in the Trends Report, the department is ensuring the public has current and correct information so that they can see for themselves the improvements that have been made."

The air quality trends report, which includes an interactive map where the user can look at concentrations from sites around the state, is available on the DNR website.

To view more information on Wisconsin's air quality, go to the DNR's web site and search for "air quality."