International Rainy-Lake of the Woods Watershed Board Water Levels Committee Announces Initial Spring Regulation Plan for Rainy and Namakan Lakes


The International Rainy-Lake of the Woods Watershed Board (IRLWWB)’s Water Levels Committee (WLC) established an initial spring regulation plan for Rainy and Namakan Lakes on March 10, 2023. This plan is issued in accordance with a new temporary supplementary Order issued by the International Joint Commission on March 3 which combines the previous high flood risk and standard rule curves for Rainy Lake. This will provide flexibility to direct dam operations as spring develops without having to employ a different rule curve.  

In accordance with the WLC spring regulation plan, the March 31st target water levels for both Rainy and Namakan Lakes will be the lower third of their respective rule curve bands. The WLC will monitor conditions over the coming weeks and provide further direction for lake level regulation prior to the end of March 2023.

The March 31st targets were established based on an evaluation of current conditions including the following factors:

  • Above-normal snow water equivalent in the headwaters, with lesser amounts to the west and closer to normal near Rainy River.
  • Groundwater supplies in the normal/slightly above normal range for the tributaries upstream of Namakan and Rainy Lakes.
  • The potential for above-normal spring flows for the US tributaries in the Rainy River Basin identified by the National Weather Service- North Central River Forecast Center.
  • Warmer than normal winter temperatures to date with lower frost depth below the ground surface.
Graphic showing Rainy Lake Rule Curve under 2023 Temporary Order

An information public session was held on February 27, 2023 which provided a summary of basin conditions and seasonal forecast information. A follow up public webinar will be hosted by the WLC in early April to provide an update on conditions as part of the spring regulation plan.

For updated information on WLC decisions, visit the IRLWWB’s Water Level Decisions & Data page.

Quick Facts

  • On February 27th, 2023 the WLC hosted a virtual public information session to provide  a summary of basin conditions and seasonal forecast information. Participants were encouraged to provide their own local knowledge and expertise and share any concerns or additional information for consideration in advance of the freshet season.
  • Feedback from participants at the February 2023 information session included observations of snow accumulation and ice conditions consistent with the information provided by the WLC. Residents around the lakes have also noted a desire for lower water levels on the lakes this spring to allow for dock and property repairs after last year’s flood event.

Associated Links


Alexandra Lavictoire (Engineering Advisor, Canada)

Abby Moore (Engineering Advisor, United States)

International Rainy-Lake of the Woods Watershed Board