The year was 1972. Hurricane Agnes had tapered off to a tropical storm, but it was still causing large amounts of flooding in Pennsylvania. I was a young child at the time, and was riding in a car somewhere in central PA with my mother and my grandfather.

We came to the edge of a bridge where both ends were flooded by the rising river (I suppose it was the Susquehanna), but the middle of the bridge was still above the water level. Somehow, my grandfather managed to spot a chipmunk out in the middle of the bridge that was trapped by the rising water on both sides. So...

He stopped the car, waded through knee deep water out onto the bridge in the pouring rain, captured the chipmunk, and brought it safely back to the car. We took the chipmunk home and I kept it as a pet for a while, but eventually released it in the yard. I don't remember whether we gave it a name or not.