Better prepared for high water? New county floodmap

On May 22, 1981, heavy rains fed snowmelt-swollen waterways to set off flooding across western Montana. In Boulder, a raging Boulder River washed away a section of Highway 69 leading to the bridge, making it impassable.

A bridge approach on U.S. Highway 91 between Butte and Helena was destroyed, and in Clancy, water from Prickly Pear Creek inundated the mill yard at Marks Pole. That was the last major flood in Jefferson County, three years after the current floodplain mapping was completed in 1978.

Now, more than 40 years later, the county is about to get a new map. Eight years in the making, the new floodplain map is more comprehensive — among other details, it now includes Prickly Pear Creek.