Officials in Canada and the U.S. have signed a new plan to regulate water levels and flows in Lake Ontario and the St. Lawrence River that they say will help restore coastal ecosystems.
The agreement, called Plan 2014, will set the flows through the Moses-Saunders Dam, which is on the St. Lawrence between Cornwall, Ont., and Massena, N.Y.
It takes effect in January and replaces an earlier water regulation system established in the 1950s.
The International Joint Commission, which signed the plan Thursday, says the previous model unnaturally compressed water levels, causing harm to the surrounding 26,000 hectares of coastal wetlands.
The commission says Plan 2014 will allow for more natural variations in water levels and help improve habitat for fish and wildlife, while still protecting against extreme high water levels that flood facilities and extreme low water levels that impact water intakes.
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In addition to rain, snow and other natural factors, water levels on Lake Ontario and the St. Lawrence are influenced by releases from the Moses-Saunders Dam on the river between Cornwall, Ontario, and Massena, New York.
Since the 1950s, the rates at which water flows through the dam have been designed to keep lake levels stable, which shoreline property owners prefer. But that approach has devastated coastal wetlands – home to fish, waterfowl, amphibians and mammals – that require fluctuating levels.
The change will also increase energy production at the Ontario Power Generation, New York Power Authority and Hydro Quebec power plants by about 0.2 per cent of their current hydropower, the commission says.
Meanwhile, there would be no impact on commercial navigation, it says, and costs due to coastal damage would increase slightly to about $20 million from roughly $18 million under the previous plan. Those costs include investments to maintain shore protection structures.
“Plan 2014 will continue to protect the people who live and work on these waters by reducing the severity and duration of extreme high and low water levels,” said Gordon Walker, the commission’s Canadian chair.
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The plan caps off a 16-year process involving studies, public engagement and government review.
The International Joint Commission was established under the Boundary Waters Treaty of 1909 to help the United States and Canada prevent and resolve disputes over the use of the waters the two countries share.
Elizabeth Hendriks of WWF-Canada said in a release that the conservation group encourages immediate implementation of the plan, as both Lake Ontario and the St. Lawrence River are at risk.
“Plan 2014 is a balanced approach to restoring a long-degraded environment while accounting for the needs of the people and industries that use it,” Hendriks said.