MASSENA -- The International Lake Ontario-St. Lawrence River Board will temporarily reduce outflows through the Moses-Saunders Dam on Oct. 7-8 in an effort to raise water levels on Lake St. Lawrence and provide a one-time opportunity to assist with end-of-season boat haul outs.

Lake St. Lawrence is the widening of the St. Lawrence River located immediately upstream of the Moses-Saunders Dam at Cornwall, Ontario, and Massena.

Decreasing the outflow through the dam has the effect of raising the water level on Lake St. Lawrence, while increasing the outflow lowers the water level. Extremely high outflows have resulted in below average water levels in this area over the past several months.

The proposed flow decrease is expected to temporarily raise Lake St. Lawrence levels, which will assist marinas, yacht clubs and other recreational boaters in the area in removal of their boats prior to winter. This will be a one-time opportunity for this year and no further flow decreases will be considered for this purpose.

The exact amount of the water level rise will vary depending on a number of factors, including location, winds and other secondary factors. Areas immediately upstream of Moses-Saunders will see the greatest increase, with up to 60 cm (24 inches) possible. These effects will be gradually reduced moving further upstream and will be insignificant beyond Iroquois, Ontario.

The relatively brief outflow reduction will also have a negligible (less than 1 cm (0.4 inch)) and temporary impact on water levels on Lake Ontario, and any such impacts will be offset by a return to higher outflows shortly afterwards. With hydrologic conditions drastically improving since the extremely wet conditions experienced during April-July the Board has determined the temporary decrease in outflow will not significantly impact the steady decline of Lake Ontario water levels.

Information on hydrologic conditions, water levels and outflows, including graphics and photos, are posted to the Board’s Facebook page at https://www.facebook.com/InternationalLakeOntarioStLawrenceRiverBoard (English), and additional information is available on its website at http://ijc.org/en_/islrbc .