The Boise River flooded in 1872 .
The Boise River cut a new channel , isolating the town on an island ; as a result , the town moved to a new location in the years after 1880 .
The Boise River flooded in 1872 and cut a new channel , isolating the town on an island ; as a result , the town moved to a new location in the years after 1880 .