A harsh winter with nearly 63 inches of snow, a sudden spring thaw and little to no water regulation combined to cause the worst flooding in Pittsburgh history: the St. Patrick’s Day flood of 1936.

Around 9 a.m. on March 17, 1936, the city’s rivers crested the 25-foot flood stage. This was not uncommon, according to Heinz History Center curator Lauren Uhl, as flooding in Pittsburgh was an annual event. But the next day, when waters surged to 46 feet, thousands of buildings were devastated.

“Anybody who was in the floodplain … it was your first flood that was up to the ceiling,” Uhl said.

While the flood significantly impacted Pittsburgh, it also affected 12 other states and many cities. Locally, buildings in the Strip District, Golden Triangle, and North Side had about a day to take whatever was stored on the lower floors and get them to higher ground. Uhl said at places like Horne’s Department Store, boats owned by the companies would be utilized to remove products from the buildings.

“They expected it, it was part of life,” Uhl said. “They knew that eventually they’d have a devastating flood.”

In the Strip District, as the water rose nuns at St. Stanislaus Kostka Parish on Smallman Street were rushing to relocate church items from the basement to the first floor, then the first floor to the second and eventually up to the third floor. Derris Jeffcoat, parish historian, said after several hours of waiting and praying for help, a lantern appeared in the distance.

“A boat came toward the convent, they couldn’t take all the sisters at one time, so three were helped into the river and taken to safety,” Jeffcoat said. “Then the boatman came back and took the other two.”

A few streets over at Klavon’s apothecary and ice cream shop, owner James Klavon and his son, Raymond, were also going through the exercise of taking stock from the basement to higher floors. But this time, unlike other years, the water rose quickly and Raymond was trapped. So, according to store’s current owner Jacob Hanchar, he ran on top of a telephone booth and snuck out a window just in time to flag down a passing boat.

“It just was serendipitous that he was able to sneak out the window and the rowboat was just coming by and he climbed right in,” Hanchar said.

The business currently has a little marker with waves to show how high the water rose in 1936.

Many people and businesses from this era have stories about the 1936 St. Patrick’s Day flood, Uhl said, which is one of the many reasons it’s so well-remembered. When the History Center did an exhibit commemorating the flood’s 70th anniversary, visitors shared their memories with curators.

“There was one woman who said, ‘I gave birth to my first son, March 19, no lights, no doctor, just a lot of water,” Uhl recalled.

Others have warm, neighborly memories of the events, Uhl said. Much like at Klavon’s and St. Stanislaus, Pittsburghers remember being rescued or going out to rescue people throughout the community.

“People are very conscious of what they do have during the Depression and they’re very generous of what they can give.”

The 1936 flood was estimated to cost about $250 million in damage to houses and businesses and time lost, Uhl said. That was enough to resurrect a conversation about the steps that local, state and federal authorities could take to mitigate the annual flooding problem. Flood legislation had been proposed in previous years, but finally after the 1936 devastation across the northeastern and mid-Atlantic states and Washington D.C., lawmakers took a serious look when Congress reconvened.

They passed the Flood Control Act of 1936, which authorized the construction of a series of locks, dams and reservoirs.

Send us in where you know there’s a 1936 flood marker and we’ll add it to this ongoing project map. Thanks to the Pittsburgh Orbit for helping with this story.