Record Great Lakes Levels Could Cause Billions In Business Losses

Rising water levels are causing delays in the St. Lawrence Seaway that could cost the economy more than $1 billion, shippers and port operators say.

A new study from the Chamber of Marine Commerce warns that opening the floodgates further at a dam in Cornwall, Ont., in order to relieve high water levels upstream would wash away between $1 billion and $1.75 billion in revenue for businesses on both sides of the border.

A board of control recently increased the flow at the Moses-Saunders Power Dam — the only control point on the St. Lawrence Seaway, which includes the Great Lakes — to allow a near-record 10,400 cubic metres of water per second out of Lake Ontario.

The rate — equivalent to about four Olympic swimming pools going over the dam each second — follows heavy spring snow melt and rains and record water levels on several Great Lakes.