Dam failure
The new river walls withstood Hurricane Agnes in 1972, but on the night of July 19, 1977, a severe thunderstorm dropped 11 inches of rain in eight hours on the watershed above the city and the rivers began to rise. By dawn, the city was under water that reached as high as . Seven counties were declared a disaster area, suffering $200 million in property damage, and 78 people died. Forty were killed by the Laurel Run Dam failure. Another 50,000 were rendered homeless as a result of this "100-year flood". Markers on a corner of City Hall at 401 Main Street show the height of the crests of the 1889, 1936, and 1977 floods.