Lake Agassiz and Hudson Strait Blowout caused by River Connected to the Atlantic Ocean.

There may have been a breach that slowly expanded in Lake Agassiz connecting to Hudson Bay or possibly occurring at the Atlantic Coast in the Hudson Strait causing the massive Lake Agassiz to drain into the Atlantic Ocean. Also, a possible ice dam may have caused a temporary block that was released when melted. Regardless, we have all seen those videos of the guy digging a small stream that connects a river to an ocean and it turns into a massive flow of water.