MASSENA - Regulators of Lake Ontario and the St. Lawrence River said Thursday they will continue to store water on the lake for future need.
The International St. Lawrence River Board of Control said its regulation plan has been responding to below-average levels on the lake by prescribing outflows that are well below average for this time of year. As a result, since the Ottawa River freshet that began in mid-April, conditions downstream have permitted only a limited amount of additional water to be stored on the lake. The board can store water on the lake by reducing outflows through the Robert Moses-Robert H. Saunders Power Dam at Massena.
In addition, while the strategy will provide environmental and recreational benefits of higher water levels upstream on Lake Ontario, the extra water stored can also be released later in the season to benefit commercial navigation and boaters in the lower St. Lawrence River. At the boards next teleconference, a decision will be made whether to retain the stored water on Lake Ontario for gradual release over a possibly dry summer and fall, or to release the extra water earlier, in response to possibly wetter conditions.
The level on Lake St. Lawrence on May 1 was 73.71 m (241.83 ft), which is 7 cm (3 in) above average due to lower than average outflows through the Moses-Saunders dam.
The board said that Lake Ontario now is slightly above its plan-specified level, but below its long-term average level, as are the other Great Lakes. The under-discharges began when the level on Lake Saint-Louis at Pointe-Claire, Que., reached 71.5 feet, about a foot below its flood-alert level. The board said it will stop storing water if the level at Pointe-Claire reaches 69.55 feet in an attempt to store up to 2 inches of water on Lake Ontario. The board will store more than 2 inches only if the level of Lake Saint-Louis is at risk of exceeding its flood-alert level of 72.5 feet.
The board said its strategy will allow it to address uncertainty of the inflows during the freshet period.