‘Deviation authority’ in winter months may soon help 2020 Lake Ontario water levels

Dec 27, 2019

High Lake Ontario water levels have been a major concern for shoreline communities in recent years. In response, New York State created the REDI commission, which plans to improve infrastructure along the southern shoreline of Lake Ontario and the St. Lawrence River. Something else that could help is increasing Lake Ontario's outflow in to the St. Lawrence River during the winter months.

Water from Lake Ontario is released into the St. Lawrence River through the Moses Saunders Power Dam in Massena.
Credit Veronica Volk / WXXI News

The International Joint Commission gave deviation authority to the International Lake Ontario-St. Lawrence River Board. That’s the board that regulates outflow numbers from Lake Ontario.

“One of the benefits of that is they looked back at 2017 high water events, 2018 high water events. They said, ‘Where in the winter time could we get more water off the lake?’ And they identified small windows, small areas that more water could have been removed from the lake if the board had deviation authority,” said U.S. Army Corps of Engineers Buffalo District Public Affairs Officer Andrew Kornacki.

Kornacki said the next opportunity where more water potentially could be pulled off the lake is after the end of the shipping season near the end of December. There’s a window where high outflows can be passed before ice starts forming.

“Conditions right now, being slightly warmer than what they typically are, might allow for extended days for that to happen,” he said. “The caveat with that is, we’re talking centimeters or inches and not feet off the lake. But every little bit helps. So having that deviation authority early and understanding what (has) happened in the past and identifying these areas that are coming up, there might be opportunity to pull more water off the lake in the winter months here.”

Lake Ontario is currently sitting around roughly 246 feet, which is a little bit higher than the long term average, but below historical maximum from previous years. In addition to that, Kornacki said the other four great lakes are trending to have higher levels overall.

“This is a typical cycle that you see with the Great Lakes. They rise and they fall,” he said. “They go through the highs and the lows and right now we are just in one of those cycles where the Great Lakes are very high right now across the board. Lake Ontario though, because of water regulation, is one of the lakes that is recovering from the high lake levels this year faster and more quickly than the other four Great Lakes.”

Kornacki said that’s all possible as long as environmental concerns and local and industrial municipal water intake is accounted for.

“You start passing too much water out of Lake Ontario, the forebay behind the Moses-Saunders Dam will drop down to a level where fresh drinking water would be impacted and people would not have access to that water,” he said. “Additionally, you let too much water out of Lake Ontario at such a high velocity, you can have shoreline erosion, you can cause erosion along the St. Lawrence River and impact roadways or public and private infrastructure.”

Lake Ontario flow was decreased back around December 21 to help ice formation in the St. Lawrence.

“So when you have these high outflows from Lake Ontario and ice starts freezing, if you don’t reduce the outflows what you could potentially do is break up that ice that started to form and cause ice jam flooding up in the upper St. Lawrence area,” Kornacki said. “That is very dangerous. It’s unpredictable and occurs in areas that flooding isn’t usually seen.”

Sometimes a reduced Lake Ontario output is needed to help the St. Lawrence River form a solid ice cover. Once that ice cover is formed, higher outputs can be passed underneath the ice without a fear of ice jam flooding.

Kornacki said what water regulation is really meant to do is help recover more quickly after extreme events.

“It’s not supposed to stop the extreme events because there is no stopping Mother Nature when that amount of water is being talked about, but what it actually does is help recover more quickly,” he said.

Still, there’s still no telling what the forecast could bring this spring. Kornacki said two weeks is about the extent of where true forecasting can tell you what is going to happen.

While the Great Lakes have seen recent highs, Lake Ontario was seeing historic low levels eight years ago. In the past there have been talks of dropping the lake levels as much as possible, even below the long term average.

“What if in 2020 we see a drought condition where all of a sudden we no longer have water? What do we do then? Lake Ontario levels will continue to drop and then all of a sudden it’s now a situation where there’s not enough water in Lake Ontario,” Kornacki said. “Not to say that’s (a forecast that) would happen, but it’s an extreme possibility.”

What’s taking place is a very careful balancing act that impacts shoreline communities along Lake Ontario and the St. Lawrence Seaway all the way up to Montreal.

So what does that mean for people and how do you prepare for that? Kornacki credits New York State for taking action with the REDI commission.

“(It’s important) making a shoreline that can accommodate these higher highs and lower lows and allowing them to happen without great impact to the residents along that shoreline,” he said.

Kornacki added it’s a very large amount of land. All of the Great Lakes southern shorelines combined is larger than any other U.S. coastline on the Pacific, Atlantic and Gulf Coast.

“So there’s quite a bit of shoreline on the Great Lakes that needs to be looked at as a whole. And I think New York State has taken really proactive measures,” he said. “I think municipalities, public and private property owners are taking the right steps to insure that their property is more resilient. Not just for the high waters, but for the low waters history has shown us are going to be coming in the future.”