St Larewncw Seaway System has isued Seaway Notice no 13 advicing on the prevailing issue of declining water levels at St Louis. The circular sets the max draft allowwd in the sector of Montreal to Lake Ontario and Welland Canal. The notice reads as below

Mariners are advised that water levels on Lake St. Louis are low and continuing to decline.

Effective August 23, 2025, the maximum permissible draft in the Montreal-Lake Ontario section will be reduced to 80.0 dm (26’-3’’) for all ships.

Reduced outflows and low water levels are expected to persist for some time. We will continue to monitor conditions closely and will advise of any change as soon as possible.

Speed restrictions remain in effect as described in the latest Montreal-Lake Ontario Notices to Shipping.

In the Welland Canal, maximum permissible draft will remain at 80.8 dm (26’-6’’) for all ships.

Ships equipped with an approved and operational Draft Information System (DIS) will continue to be permitted to transit at a draft of up to 7cm (3”) above the maximum allowable draft. August 12, 2025