Air Pollution

Photo Credit: © 2009 BlairPhotoEVV

Danger from the Air

Each year, more than 85 million pounds of nitrogen pollution*—about one-third of the Bay's total yearly load—comes from air pollution.

At more than 18 million, there are more people in the Chesapeake Bay watershed today than ever before. It is estimated an additional 157,000 people move into the region every year, bringing with them more vehicles and more demands for energy from power plants. And as a result, more air and nitrogen pollution will damage the Bay.

Most airborne nitrogen pollution is from power plant smokestacks and vehicle exhaust. The Baltimore-Washington metropolitan region has the nation's second worst traffic and ozone problems. But this air pollution isn't coming from just the watershed. It is carried on the wind from as far away as Canada in the north and Indiana and Kentucky in the west. This "airshed" is 570,000 square miles—more than nine times the watershed itself.

Nitrogen washes out of the air in rain, falling into the Bay and contributing to algal blooms. These blooms cloud the water and absorb the oxygen, creating dead zones in the Bay that cannot support underwater grasses, crabs, fish, and other marine life.

According to the EPA, nitrogen pollution from coal-burning power plants and vehicle tailpipes is far cheaper to control before it is released into the air. Experts estimate the cost differential at about $2 to $3 per pound, versus $150 per pound for controlling nitrogen pollution at the smokestack or tailpipe. It could be cheaper still to control pollution by changing our patterns of land use to reduce our need to drive everywhere.

Air pollution, primarily from power plants, is also the main source of the mercury that contaminates fish in the Bay watershed. As a result, anglers are warned to limit their consumption of certain fish species due to potentially harmful levels of this toxic chemical. After a successful legal challenge from environmental groups, including CBF, EPA recently promulgated regulations to limit mercury pollution from the nation's coal-fired power plants. Unfortunately, regulations focused on reductions in nitrogen oxide and sulfur dioxide emissions have been delayed by industry lawsuits.

Unhealthy air doesn't have to be part of life in the Bay. Alternative and renewable energy sources and low-emission vehicles should be part of our national strategy to reduce pollution from smokestacks and tailpipes. Smart land use planning and innovative means of transportation are also key pieces of the pollution puzzle. Nutrient trading is another option.

Every Bay-loving citizen and stakeholder should demand that state and federal leaders act to enforce air quality standards and promote innovative ways to reduce pollution from airborne sources.

*Based on 2014 data from the Chesapeake Bay Program Watershed Model 5.3.2


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