A numerical model study on Saint John River ice breakup

Abstract

Ice jam floods are frequent occurrences throughout the Saint John River. Spring ice breakup, due to the freshet, are the most common and damaging. A coupled two-dimensional hydro and ice dynamics model was used to study the breakup and jamming processes on the 64 km reach of the Saint John River between Grand Falls and the Beechwood Generation Station. The model simulated the evolution of the 2012 ice breakup and jamming event, which caused record high flooding. The simulated results compared well with observed data and provided detailed information on the breakup processes. The study showed that both failure due to accumulation of ice at the cover leading edge and failure due to high rates of water level change from surges were important ice breakup processes. It was also found that one of the most significant factors in the flooding at Perth–Andover was the release of ice from above Grand Falls.