St. Lawrence River record flows continue through mid-August

The St. Lawrence River in Cornwall, Ont. near the RCAFA boat launch. (Newswatch Group/Bill Kingston, File)

CORNWALL, Ont. – The record outflow from the St. Lawrence River is expected to continue through the middle of August.

That’s according to projections by the International Lake Ontario-St. Lawrence River Board, which met Friday (July 5).

The river dam system is currently pumping out 10,400 cubic meters of water per second (367,270 cubic feet per second), which is 200 cubic meters (7,060 cubic feet per second) higher than the limit set under Plan 2014.

The board looked at moving the flows even higher, but that would require shutting the seaway down to commercial boat traffic, which it estimates would cost the shipping economy about $50 million a day.

The long term objective is to move enough water out of Lake Ontario to drop the lake more than 30 centimeters (1 foot) to below 75.5 meters (247.7 feet).

Meantime, the International Joint Commission has asked the Great Lakes-St. Lawrence River Adaptive Management Committee to step up its ongoing review of Plan 2014.

A statement on that assessment is expected later this week.