Where the entire area from New England to Quebec will find an overall rise in sea level due to the tearing of the St. Lawrence Seaway during the shift, New Brunswick, as the tip of the peninsula past which water will rush, will deal with special issues. Those along the inner seaway will find the ride rocky but relatively safe, as the tearing process will provide a broader bowl for water to slosh about in, for rivers to empty into, and thus flooding along the inner seaway will be less of a worry than along other rivers or lake coastlines. The tearing seaway, with an overall drop in sea level within the seaway, will, however, cause water in the Atlantic to pour into the seaway, seeking its level, and this rush will be past and thus to some extent into the New Brunswick peninsula. Those in this province are advised to stay well inland and in high ground, anticipating water not only rushing past the tip of the peninsula at the lip of the seaway, but overland when water pressure into the seaway does not relieve the press from the Atlantic.
Note East Coast Migration commentary.