All cities possess environmental stories, but there is probably no city in the nation that surpasses Pittsburgh in terms of the scope of its air, water and land pollution history. The city's geographical site and location on major rivers; its natural resource endowments, particularly bituminous coal; and its development as one of the world's most industrialized cities for much of the period from 1850 to 1980 largely shaped its environmental history. This environmental history can best be examined by considering the media of air, water, and land.
Smoke pollution was the most visible byproduct of coal consumption, with atmospheric inversions in the city and in the region exacerbating conditions. Smoke's link with industrial prosperity made control of the problem difficult. A smoke control movement developed after the city experienced a brief clean air period in the 1880s and early 1890s due to a brief natural gas boom. But smoke control ordinances and a Bureau of Smoke Control produced only minimal results because of weak regulations and enforcement, and imperfect control technologies.
Pittsburgh and its region still have considerable water pollution problems because of problematic sewer systems. Pittsburgh, for instance, has a combined sewer system that cannot accommodate all wastewater flows. Raw sewage, therefore, enters the river on wet weather days, causing violations of the Clean Water Act as do overflows from communities with sanitary sewers. However, the rivers are still heavily used for recreational purposes and fish species are abundant.
Over the course of decades of intense industrialism and coal mining, the land and the ground water in the Pittsburgh region were also polluted. In addition to the coal mine waste, much of which was cleaned up during the 1950s and 1960s, the metal industry also disfigured the landscape through its disposal of slag, the waste metal produced in steelmaking. Huge piles of slag can still be found around the region.
Pittsburgh and its surrounding region have made substantial improvements in environmental quality over the past half-century. The skies are cleaner, the rivers are full of fish and lined by bike trails and new buildings, and brownfields have been restored to productive and sustainable use. These gains have been accomplished by a combination of purposeful action and non-regulatory factors such as the collapse of the steel industry.
But a number of problems remain, such as wet weather pollution of the rivers and development of greenfield sites. Today, pollution from the by-products of coking facilities and automobiles are the greatest source of air pollution in the region. Dealing with these will require powerful leadership by elected officials and environmental organizations throughout the entire region who can unite on the common goal of further environmental improvement. And even with its minor problems, Pittsburgh isn’t the Smoky City anymore. The deadly air pollution that hung over Pittsburgh’s steel mills for nearly 150 years is gone, and the region has undergone a dramatic environmental transformation.
All cities possess environmental stories, but there is probably no city in the nation that surpasses 
