Donora

Donora is a borough in Washington County, Pennsylvania, United States. It lies along the Monongahela River in the western Pennsylvania region known as the Mon Valley and is part of the Pittsburgh metropolitan area.

Donora developed during the late 19th and early 20th centuries as an industrial community centered on steel, zinc, and other manufacturing. The presence of mills, factories, and related services attracted workers and contributed to population growth. Like many towns in the Mon Valley, Donora experienced economic challenges after the decline of heavy industry in the latter half of the 20th century, leading to changes in employment and population.

The Donora Smog of October 1948 was a defining event in the town's history. A weather inversion trapped emissions from local factories and other sources, producing several days of dense air pollution. The episode caused respiratory illness and multiple deaths and drew attention to air-quality and public-health concerns, contributing to reforms in air-pollution regulation and monitoring in the United States.

In contemporary times, Donora maintains a small, residential community within the Pittsburgh region. Local governance operates under a borough structure with a mayor and elected council. The town’s institutions, landmarks, and cultural heritage reflect its industrial past and ongoing efforts at neighborhood revitalization and public service.