River ice breakup flood forecasting

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River ice breakup can be instigated by spring runoff, mid-winter thaws, and hydro-peaking operations, and is a crucial event on Canadian rivers because of its economic and ecological impacts. The breakup period features frequent ice jam events which can result in severe and hard-to-predict flooding; further, when formed in place, ice jams can create physical barriers that impede navigation. When ice jams release, they can produce destructive high-speed water waves and ice runs that can damage infrastructure, cause bank and bed erosion, and endanger or even sink shipping. Because of the risks posed by ice jams, hydro-peaking operations often need to be modified to avoid triggering their formation and release, thus limiting hydro-power production. Ice jam events may adversely impact river ecosystems but in some cases can also provide essential replenishment to the river systems (e.g. Mackenzie River Delta). For all these reasons, it is therefore desirable to understand river breakup and ice jam phenomena and to be able to predict their occurrence with greater accuracy. The challenge is that the presence of ice, interacting with the dynamic flow in various ways, makes forecasting these events very difficult.