Applicability of 2-D modeling for forecasting ice jam flood levels in the Hay River Delta, Canada

Abstract

Ice jam floods can present an annual threat to communities adjacent to rivers, especially those situated at river confluences, island or deltas. The objective of this study was to determine whether 2-D modeling might be used to predict expected ice jam flood elevations for such multi-channel systems. The Hay River delta was selected as the demonstration site for this study, and 2-D modeling was employed to calculate ice jam flood levels expected for varying inflow discharge conditions. The River2D model was calibrated for historical ice jam profiles covering a range of discharges from 268 to 1000 m3/s and a relationship was developed to predict the flow split down the East and West Channels based on the inflow discharge to the delta. Also, ice jam rating curves were developed at 0.5 km intervals along each channel facilitating the development of an ice jam profile prediction tool for use by the Town of Hay River.