Pittsburgh flood of 1936

On March 17 and 18, 1936, the city of Pittsburgh, Pennsylvania witnessed the worst flood in its history when flood levels peaked at 46 feet (14 m). This flood became known as The Great St. Patrick’s Day flood, and also affected other areas of the Mid-Atlantic on both sides of the Eastern Continental Divide.

Civic organizations in the city, with financial backing from the City of Pittsburgh, Allegheny County and the Chamber of Commerce had been asking the Federal Government for help with flood control for almost thirty years. They had formed committees to lobby government officials and found themselves caught in political processes that ultimately resulted in the city and its residents sustaining devastating damage. In August 1935, the United States House of Representatives passed a bill for nine flood control reservoirs to be built above Pittsburgh. However, while the Senate debated this bill, the tremendous 1936 flood occurred. The Congress did not actually appropriate any funds for the project until the 1937 flood which threatened, but spared the city and went on to devastate the Ohio River Valley.

On March 16, 1936, warmer-than-normal temperatures and torrential rain followed a cold and snowy winter, leading to the rapid melting of snow and ice on the upper Allegheny and Monongahela rivers. These rivers and their tributaries were already over their banks and were threatening the city of Pittsburgh. On March 17, 1936 the waters reached flood stage of 25 feet. Heavy rains overnight caused the waters to rise quickly, and on March 18, the water peaked at about 46 feet, 21 feet above flood stage. Five days later, on March 21, the water finally receded to 24 feet.

The aftermath to the city was devastating. About 100,000 buildings were destroyed and the damage was estimated at about $250 million ($4.37 billion today). Steel mills that were located around the three rivers suffered devastating damage and 60,000 steel workers within a thirty-mile radius were out of work due to the damage that the mills suffered. Sixty five percent of the downtown business district had been under water from the Point all the way up to Grant Street.

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