Formation, collapse and composition of ice banks in a macrotidal channel of the Bay of Fundy

Abstract Large ice blocks containing enough sediment to be denser than sea water form in the Minas Basin of the Bay of Fundy, Canada. Ice block composition and the timing of ice block formation were monitored to improve understanding of the potential threat to tidal power generators posed by collision with ice blocks. Field studies were carried out in 2012 and 2013 in the Kennetcook River, which is a tributary of the Minas Basin of the Bay of Fundy. In 2012, the cross-sectional area of the channel at the study site decreased by 21% due to the formation of ice walls. In 2013, it decreased by 24%. Large ice blocks separated from the ice walls during spring tides following a time lag of the minimum air temperature. The time lag was 20 days in 2012 and 21 days in 2013. Eleven percent of samples from ice blocks were denser than sea water.