Observations of ice jam release waves on the Athabasca River near Fort McMurray, Alberta

Abstract

This paper presents an investigation of all documented ice jam release events for the Athabasca River at Fort McMurray, Alberta. A review of the historical records indicates that release waves in excess of 3 m and propagation speeds of 4–5 m/s are not uncommon. Numerous occurrences of increases in wave speed and magnitude suggest that temporary stalling of ice runs may be a significant factor in release event propagation. Detailed measurements of ice jam release events in 2001–2003, including most notably a 4.3 m high release wave measured in 2002, provide unprecedented data describing ice jam release wave propagation and suggest that continued propagation of a portion of the release wave downstream of a reformed jam could be a significant factor in immediate re-release.Key words: ice jam, floods, flood forecasting, river ice, ice jam release.