Chris Glover MPP, Spadina–Fort York

Government of Ontario

IJC Water Levels Webinar April 3, 2020

Published on April 6, 2020

International Joint Commission (IJC)

Lake Ontario-St. Lawrence River Water Levels Webinar

April 3, 2020

SPEAKER: Jane Corwin, US Co-Chair

    • Lakes Erie and Superior will hit new record highs if it’s a wet year. Lake Superior will peak in August.
    • Lake Erie is at a record-high level and water is flowing into Lake Ontario at a record rate. 85% of Lake Ontario water comes from Lake Erie.
    • IJC now deviating from Plan 2014 to increase outflows beyond recommendations to accommodate increased water intake
    • Now allowing above-normal water levels near Montreal to accommodate Lake Ontario
    • Moses-Saunders Dam is the only way to directly influence Lake Ontario and Lake St. Louis water levels.
    • Moses Saunders dam at Cornwall outflow Jan-March 2020: 9,500 cm3/sec
    • Flooding up and downstream from the dam in 2019
    • Opening date for shipping is up to the Seaway Corporation
    • April 1st, determining how much outflow can be allowed without endangering mariners
    • IJC communicates with Seaway and gives advice on shipping date
    • IJC advice resulted in the delay of shipping to remove extra water through March 2020
  • Flow limits for downstream flood levels and limits for Seaway are similar.
  • Suspending navigation wouldn’t allow you to move any more water. 
  • Ice season was shorter this year and that allowed them to increase outflows.
  • No limit on the rising of water levels in Lake Ontario
  • IJC states that having a limit for Lake Ontario is unnecessary as the limits are often ignored in favour of best judgement.
  • Cannot increase flooding downstream more than would have occurred with natural conditions.
  • Removing 1cm of water in Lake Ontario means adding 11cm in Montreal 



Why are outflows less than around February 27th?

  • There is so much water that it is hard to release as much as is coming in.
  • Ice flow blockage also impacts outflow levels.

Would limiting shipping hours allow for increased outflow levels?

  • Ships cannot stop in the middle of their trip.
  • Time limits would have limited impact on shipping anyway.

Where can we see the minutes of IJC Board meetings?

  • Minutes can be found on the IJC website
  • Worth noting that the IJC operates by consensus not majority decision

What is being done to lower levels in Georgian Bay?

  • IJC has no mechanism to impact Georgian Bay.

Can the St. Lawrence be dredged?

  • Yes, but all that water would end up downstream.

Can mitigation measures be implemented only if shipping is not affected?

  • No

How long does it take for water from Lake Superior to get to Lake Ontario?

  • Two years

Where can water level and outflow information be found?

Will the IJC consider ending the shipping season early?

  • That has been considered but it would have minimal impact on increasing outflow levels.