A thick plume from a smokestack smudges Madison's hazy skyline in 1977.
PHOTO: Dean Tvedt
A cloudy picture
With recycling so prevalent today, it s hard to believe that in 1970 one of the most common practices in Wisconsin was the open burning of trash at hundreds of town dumps. Officials received many complaints about smoke and odors from dumps and other sources.
Black, grey, yellow or brown smoke also belched from countless smokestacks around the state, especially in Milwaukee County, the upper Wisconsin River valley and the lower Fox River area. Automobiles burned leaded gas back then, and so inefficiently that unburned fumes reacted in sunlight to cloud southeastern Wisconsin skies with summertime smog.
The first clean air projects
Back then, local pollutants such as suspended particulates (smoke, soot and dust) and gaseous sulfur dioxide were seen as the primary threat to human and environmental health. Even before the federal Clean Air Act was passed in 1970, Wisconsin had already set standards and begun yearly statewide monitoring for several major air pollutants. Monitoring took place in 18 cities across Wisconsin, but concentrated in industrial Milwaukee County.
The Wisconsin Department of Natural Resources (which had been formed in 1968) completed an emissions inventory by identifying 320 sources of air pollution around the state, then developed a plan to meet statewide pollution standards. This plan included issuing state and county orders that required dischargers to control their emissions. Prosecution became a possibility for severe offenders. The state also hoped to reduce heavy smoke and odors in rural areas by halting garbage-burning at waste dumps and converting these into sanitary landfills.
A thick plume from a smokestack smudges Madison's hazy skyline in 1977.
PHOTO: Dean Tvedt
Despite these efforts, in general the state lacked the resources and legal means to really control polluters. But air pollution control had started 120 industries and a few counties did submit state compliance plans or met air quality standards in 1970.
Success in controlling local air pollution
Since 1970, Wisconsin s skies have cleared dramatically. Air quality monitoring at 45 permanent sites across Wisconsin over the past 25 years shows that concentrations of sulfur dioxide, carbon monoxide, nitrogen oxides and particulates have fallen well below national standards.
The control of serious localized air pollutants has been a great success thanks to the use of emission permits, state and national mandates, and voluntary actions by industries as diverse as utilities and automobile manufacturers. Power plants, paper mills and other facilities now meet even stricter requirements for sulfur dioxide emissions mandated by 1990 amendments to the federal Clean Air Act.
*based on standards at the time of measurement
Lead levels in Wisconsin have dropped as much as 90 percent in the past 10 years due mostly to the substitution of unleaded gasoline for the old leaded variety. Lead levels in Milwaukee County are now so low they hardly register on current scientific instruments.
Emissions of chloroform, formaldehyde and more than 400 other toxic air pollutants that threaten human health were limited under a 1988 Wisconsin rule, providing an added public health safeguard that only a handful of states currently offer.
Focusing on regional air pollution
With localized pollution problems largely eliminated, during the last 10 years problems with regional pollution have taken center stage in Wisconsin. An early movement to control regional pollutants concentrated on acid deposition (acid rain), a threat to sensitive lakes in northern Wisconsin whose fish and other organisms could have succumbed over time to increasing levels of acidity if preventive action hadn t been taken.
Wisconsin didn t wait to act. The state passed the strictest and most comprehensive acid rain control legislation in the country in 1986 and invested millions in acid rain research. The law worked, and research findings documented results.
Today, rivers and lakes show lower acid readings than they did 10 years ago. New federal requirements and regional state partnerships will limit acid rain s transformation into an interstate and international pollution problem.
Fighting ground-level ozone
The toughest challenge remaining for Wisconsin in terms of regional air pollution is ground-level ozone, the main ingredient of smog. Ground-level ozone has been regulated for 25 years through strict controls on industries, automobile emission standards and cleaner fuel requirements. Yet 11 southeastern Wisconsin counties are still classified as ozone problem areas.
The fight against ozone continues but the effort has shifted from regulating not only industry but also to encouraging people to change daily habits in ways that reduce air pollutants from automobiles and other sources.
These maps compare which counties in the 1970s versus the 1990s were officially
designated as failing to meed federal standards for healthful air quality. Wisconsin had made great
strides in reducing several major air pollutants.
For example, about 600 large companies are setting up programs to reduce solo driving to work by about 215,000 southeastern Wisconsin employees. Reformulated gasoline must be sold in six southeastern counties to curb problem ozone, but earlier this year consumer complaints about the new fuel s impacts on their health, fuel efficiency and pocketbooks prompted the Governor to request a temporary waiver from the requirement to sell the fuel. The federal government denied the waiver, but is cooperating with the state to investigate health and other complaints and providing better information about the new fuel s connection with cleaner air.
Ground-level ozone travels via prevailing winds. As much as half of Wisconsin s ground-level ozone wafts into the state from outside the Lake Michigan region while our ozone is blown into Michigan and other states. This condition points to the continuing need for national clean- air efforts that reduce the transport of pollution from one region into another.
High-ozone days decline
Despite these difficulties in dealing with ground-level
ozone pollution,
the number of days Wisconsin failed to meet the federal
standard for ozone
dropped to two in 1992 and 1993 and five in 1994. Though a
long hot summer could
reverse that trend, the last few years have brought the
lowest number of problem
ozone days in the past 25 years.
Southeastern Wisconsin residents are warned to stay indoors or curtail outdoor activity when ozone reaches unhealthy levels. PHOTO: WI DNR
Global air pollution
Wisconsin s experiences with regional air quality problems have made the state sensitive to air quality problems of global magnitude, including:
depletion of
the Earth s upper ozone layer. This is the good ozone that
shields us from harmful
ultra-violet rays, not the ground-
level ozone formed from
human activities. The upper ozone layer is being damaged by
chlorofluorocarbons,
which are used in refrigerants.
Since 1070, the
greenhouse effect, caused by a build-up of carbon dioxide in
the atmosphere from fossil fuel combustion that could raise
planetary temperatures
enough to change the Earth s climate.
toxic air
pollutants such as mercury or pesticides that are absorbed
into fish, wildlife and people with potentially harmful
results.
Local incidents of air pollution can result from accidents, such as this 1986 fire at a huge tire pile in Somerset, Wisconsin. PHOTO: David L. Sperling
When scientific evidence revealed an ozone hole opening up over the Arctic, Wisconsin in 1990 passed one of the most comprehensive laws in the nation to control the use and release of ozone-destroying substances used in auto air conditioners, appliances and industrial equipment. The federal Clean Air Act amendments of 1990 also added new national controls to combat this problem.
Governor s Alternative Fuels Task Force
To evaluate the uses of cleaner burning fuels, Governor Tommy G. Thompson created a task force in 1990 to study fuel alternatives to traditional gasoline. A laboratory was funded to test compressed natural gas, ethanol, methanol, propane and reformulated gasoline. In 1991, a local grant program offered $150,000 to convert 80 municipal vehicles such as squad cars and dump trucks to run on propane or compressed natural gas. Funding increased to $225,000 in 1992. The State of Wisconsin has also purchased 12 ethanol-run Chevrolet Luminas.