Ice Jam on the Niobrara River

Time-lapse photography of the transition from fall-to-winter, the buildup of shelf ice, flow constriction, and jamming of river ice along the Niobrara River in the Fort Niobrara National Wildlife Refuge in north-central Nebraska. Flow in the photos is from left to right. Photography was taken along the south (right) bank approximately 2.1 miles upstream from USGS streamflow-gaging station 06461500. The rapid change of lens angle in final days of sequence is due to pressure from ice jamming on the flood plain pushing against the tree where the camera was mounted. The camera was approximately 6 feet above the 2-year flood plain, and was eventually flooded, presumably due to backwater from ice jamming, causing shutdown.