This Week in Illinois History: Fighting Winter Floods with Dynamite (late January to early February, 1938)
In January 1938, a cold winter with little snowfall created thicker-than-usual ice on Northern Illinois’ rivers. Then in late January a warm spell ushered in heavy rains that inundated waterways. The flooding lifted and broke the thick river ice, creating treacherous ice flows.
The ice flows of 1938 were fast, large and unpredictable. They destroyed boats and barges, barreled through bridges, and broke over riverbanks. When too much ice pressed against a bridge or became trapped in a narrow river bend, it created an ice jam. Water couldn’t push through the ice jams, so it went around them, flooding farms and nearby towns and washing out roads and bridges.
Ice jams and flooding were particularly dangerous along the Rock River, endangering communities from southern Rockford to Rock Island. Thousands of residents evacuated in near-zero temperatures. Power and telephone poles washed away, leaving many without electricity or means of communication. Communities resorted to a tried-and-true method of ice removal: dynamite.
Dynamite had been used to clear clogged rivers for decades, but it was dangerous business. Severe ice jams could require several tons of the explosive. And it had to be carried, lowered or thrown onto the ice.
Ice blasting commenced in Rock Island and Rockford in late January and continued across northern Illinois into February. A successfully cleared ice jam immediately relieved flooding. Eventually, colder weather slowed the ice flows, removing the danger.