When the U.S. Army Went to War with the Susquehanna River

This episode explores one of the most dramatic—and unusual—responses to a natural disaster in Susquehanna Valley history: the March 1920 bombing of an ice gorge on the Susquehanna River. After an extraordinary eighty-three-day deep freeze, massive ice jams formed along the river, threatening catastrophic flooding in communities such as Port Deposit and placing homes, bridges, and industries at risk.

With conventional methods failing, authorities turned to an experimental solution. Army aviators from Aberdeen Proving Ground were dispatched to conduct aerial bombing runs, dropping thousands of pounds of TNT onto the frozen river. Early missions using smaller charges proved largely ineffective, but the deployment of 500-pound bombs finally shattered the ice gorges and set the river moving once again.

Drawing on newspaper accounts and eyewitness reports, this episode recounts the spectacle of explosions echoing through the valley and examines the mixed results of this radical intervention. The Susquehanna Ice Gorge Bombing remains a singular moment when military tactics were repurposed to battle winter itself—revealing how far communities once went to protect lives and infrastructure from the immense power of moving ice.

To learn more, visit UnchartedLancaster.com.

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