Assessment of annual high-water events for the Mackenzie River basin, Canada

River ice break-up is known to have important morphological, ecological and socio-economic effects on cold-regions river environments. One of the most persistent effects of the spring break-up period is the occurrence of high-water events. A return-period assessment of maximum annual nominal water depths occurring during the spring break-up and open-water season at 28 Water Survey of Canada hydrometric sites over the 1913?2002 time period in the Mackenzie River basin is presented. For the return periods assessed, 13 (14) stations are dominated by peak events occurring during the spring break-up (open-water) season. One location is determined to have a mixed signal. A regime classification is proposed to separate ice- and open-water [...]