Another Seaway season is underway after a near two-week delay helped reduce water levels throughout the system.
The St. Lawrence Seaway resumed operation on Wednesday – about 12 days later than it normally would – giving the authorities more time to let as much water out of Lake Ontario before spring as possible.
And, from what the International Joint Commission (IJC) is saying, it seems to have worked – even if marginally.
The delayed shipping season meant the IJC had those 12 extra days where it didn’t need to consider the safety of ships in the water, and since there was practically no ice in the river this year, it was able to open the floodgates like never before.
Jane Corwin, co-chair of the IJC, said during an online seminar on Friday the board was able to remove 2.7 cm more water from Lake Ontario in the last week of March.
Though the shipping season is now up and running, officials recognize it’s a critical time in terms of mitigating the risk of catastrophic flooding. The board said it will continue to “increase outflows as quickly and as much as possible above the Plan 2014 safe navigation limit” even though shipping season is underway.
“The Seaway is prepared for that. They know outflows will be increasing,” Corwin said.
“We’re preparing to go as high as possible and the Seaway is aware of that and working with us.”
The shipping industry has implemented safety measures for ships including reduced speeds, weight restrictions, having tugboats available to assist with steering, and making sure two ships aren’t passing in narrow points of the river.
And just because the extended shipping break allowed the board to release more water, Corwin clarified the idea of keeping the Seaway closed any longer isn’t an option.
Keeping navigation closed wouldn’t necessarily mean they could let more water off – that depends on precipitation and other factors like the Ottawa River – and it would have more negative impacts than positive, she said.
A further extended closure would too drastically affect the shipping industry, resulting in lost business and lost jobs, she said.
There actually wouldn’t even be a benefit to delaying the navigation season further because much of the water level depends on the seasonal rise of the Great Lakes, precipitation, and the Ottawa River, she added.
“We wouldn’t be able to remove more water,” said Corwin.
“We’re getting a lot of water out of the lake, but we’re still getting a lot of water coming into the lake, and it’s going to stay that way for a while.”
The IJC’s International Lake Ontario – St. Lawrence River Board has set its sights on increasing water levels specifically in Lake St. Louis, which is downstream of the Moses-Saunders Dam in Cornwall, as long as it’s safe to do so. This is being done to keep releasing as much water as possible from Lake Ontario, which currently sits at 75.24 m (246.8 ft) – above average for this time of year.
Whether or not there is flooding this spring depends largely on how much precipitation we get, Corwin said. If conditions are wet this year, Lake Ontario could peak higher than even last year – a possibility, she said, that concerns her greatly.
She added waterfront residents should “look more to resiliency as a way to protect themselves against high water.”
All of these increases to water outflow haven’t just been happening in the last few weeks, either, she said; the board has been preparing for spring for months.
In the three months preceding the beginning of the shipping season, the board was able to let an unprecedented amount of water out this winter.
A lack of ice formation, along with previously-implemented deviation from its water management strategies, allowed the board to “surpass the historical record-high outflows for the month of March,” making it the third straight monthly record.
“These are the highest releases ever recorded for each of these three months,” Corwin said on Friday.
The additional water they hope to remove from Lake Ontario will only amount to a few centimeters, they said, which is “small in comparison to what is already being removed by the rules of Plan 2014, and also in comparison to the seasonal increase of water supplies into the Ontario basin.”
Nonetheless, the IJC recognizes that timing is critical and will continue to let as much water out as possible, she said.