Dry conditions resulting in continued low St. Lawrence Seaway water levels
Saturday, November 10, 2012 - 5:30 pm

The persistent dry conditions in the region have prompted the International St. Lawrence River Board of Control to continue sending more water downstream than usual from the St. Lawrence River and Lake Ontario to maintain adequate water levels for the Port of Montreal.

The levels are also a concern for those who own houses on the shore and boating concerns such as shippers and fishing charter operators.

The water levels on Lake Ontario and at Montreal are well below average, setting a record at Montreal in September, while the level on Lake St. Lawrence, which encompasses roughly the area of the river off of St. Lawrence County, are slightly above average., the board reports.

The level on Lake Ontario as of Oct. 17 was 74.32 m (243.83 ft), still 17 cm (6.7 in) above the lower regulatory limit but 30 cm (11.8 in) below the long-term average for this time of year. Currently, the level of the lake is about 5.7 cm (2.2 in) lower than it would have been had the board’s plan been strictly followed this year.

Levels on Lake Ontario are the lowest for this time of the year since 1964.

Levels on Lake St. Lawrence are at 73.11 m (239.86 ft), 2 cm (0.8 in) above average for this time of the year.

The level at the Port of Montreal on Oct. 17 was 5.48 m (17.98 ft), 80 cm (31.5 in) below average. The average September level in Montreal was a new record low, in large part because outflows from the Ottawa River have also been at record low values, due to the persistent drought conditions in the region.

When conditions downstream permit, the board says it will reduce outflow to restore water levels.

“The Board, in conjunction with its staff, continues to monitor the drought situation carefully and is prepared to take further action as required, while also understanding that the drought conditions may persist into next summer, severely restricting what the Board may be able to do,” a statement from the board said.

Water levels on both Lake Ontario and the St. Lawrence River vary considerably from year to year depending on the weather conditions.

“The Board urges everyone to be prepared to live within the full range of levels that have occurred.”