The history of coal smoke in Pittsburgh is one of the most well-known examples of environmental pollution in American history.
At its height, the smoke produced by the city’s industries was so thick that it was said to block out the sun. The scale of the problem is revealed in these pictures from the Smoke Control Lantern Slide Collection at the archives of the University of Pittsburgh.
The smoke, which lasted for decades, had a significant impact on the health and quality of life of Pittsburgh’s residents, as well as on the environment.
The problem began in the late 19th century when Pittsburgh emerged as one of the world’s leading industrial centers.
The city’s steel mills and factories burned massive amounts of coal to power their operations, producing huge amounts of smoke and other pollutants. By 1816, the year Pittsburgh was incorporated as a city, it was already known for being constantly covered in a thick fog of coal dust.
In 1883, travel writer Willard Glazer wrote: “In truth, Pittsburgh is a smoky, dismal city at her best. At her worst, nothing darker, dingier, or more dispiriting can be imagined.”
Herbert Spencer, the great British philosopher, who was brought to Pittsburgh by his admirer Andrew Carnegie, put it more succinctly: “Six months’ residence in Pittsburgh would justify suicide.”
The issue of burning coal and producing smoke has long been a complex matter here because, for many people, smoke meant progress. When were the steel mills not smoking? They were not smoking during economic depressions.
Of course, the smoke had many devastating effects on the city and the way people lived. Some of the most famous were the conditions downtown at midday when street lights had to be turned on.
The vegetation around the city was also affected; in contrast to the very green city of today, before smoke-control many of the hills were completely denuded by the fumes. The city had acid rain before they even invented the term.
Efforts to address the problem of coal smoke in Pittsburgh began in the early 20th century, as public awareness of the issue grew.
In 1911, the city passed its first air pollution control ordinance, which required industries to reduce their smoke emissions.
This was followed by a series of other regulations and initiatives aimed at curbing pollution, including the creation of the Allegheny County Health Department in 1924.
Despite these efforts, the problem persisted for several more decades. In 1941, influenced by a similar policy introduced in St. Louis four years earlier, the city of Pittsburgh passed a law designed to reduce coal production in pursuit of cleaner air.
Not willing to cripple such an important part of the local economy, it promised to clean the air by using treated local coal. The new policy ended up not being fully enacted until after World War II.
Eventually, natural gas was piped into the city. This provoked a rapid changeover: between 1945 and 1950, more than half of Pittsburgh’s households switched from coal to natural gas.
Another major technological change that occurred around this time was the shift from coal-burning locomotives to diesel-electric.
In 1950, the United States had 35,000 coal-burning locomotives; by 1954, there were 350. This was one of the most rapid technological transformations in United States history, and of course it too made a big difference in Pittsburgh and around the nation in regard to air quality.
Today, Pittsburgh’s air quality has improved significantly, and the city is no longer plagued by the thick clouds of smoke that once characterized it.
However, the legacy of coal smoke pollution is still felt in the city, and efforts to address the issue continue.
These include initiatives aimed at reducing emissions from cars and other sources, as well as ongoing efforts to clean up the city’s waterways and restore its natural habitats.