Riverbank Erosion in the Colville Delta, Alaska

the Colville River delta, located on the Arctic Ocean in northern Alaska, is in the zone of continuous permafrost. The delta's distributaries, which are ice covered for over eight months of the year, are subjected to high discharge rates for three to four weeks during the snow melt period in late May and June. At this time bank erosion is likely to occur along as much as 60% of the banks of the main channels. Although average erosion rates may range up to 4 m per year, variability is great both temporally and spatially.