IKLBC Winter 2026 Conditions Update
Date

The International Kootenay Lake Board of Control (the Board) is reporting that Kootenay Lake levels remain in compliance with the International Joint Commission’s (IJC) 1938 Order of Approval which sets the limit for maximum lake levels. The Order does not prescribe a minimum lake elevation.

Kootenay Lake continues to decline in accordance with the IJC’s Order of Approval rule curve for the winter period (Figure 1). Levels on Kootenay Lake are affected in part by the Corra Linn Dam which is operated by Fortis BC. 

Graph depicting Kootenay lake levels in February 2026

 

Figure 1: Kootenay Lake levels at Queens Bay (green) and Nelson (orange), lake outflow control by Corra Linn Dam (light blue) or Grohman Narrows (purple), and the International Joint Commission 1938 Order of Approval Rule Curve for 2025 (red). Credit: FortisBC (data) and Environment and Climate Change Canada (plot), 2026.

Corra Linn Dam will be operated to decrease the lake level at Queens Bay to 1739.32 feet (530.14 meters) by April 1st, then will hold below 1739.32 feet (530.14 meters) until the commencement of spring rise has been declared by the Board, which corresponds with the beginning of the spring freshet. During that time, when lake inflow is increasing and Kootenay Lake is rising, Grohman Narrows (not Corra Linn Dam) limits the maximum outflow from Kootenay Lake. Please consult the Board’s web Visualization Tool of Kootenay Lake levels to see how Corra Linn and the Grohman Narrows interact over the year.

During the spring freshet, the maximum allowable level of Kootenay Lake is calculated based on a lowering formula defined in the Order until the lake returns to an elevation of 1743.32 feet (531.36 m) as measured at Nelson, British Columbia. Reaching 1743.32 feet at Nelson will mark the end of the freshet period for the Kootenay Lake basin. 

Record high winter temperature across the basin have resulted in a highly unusual lack of snow at lower elevations and near average snowpack at higher elevations in Canada. In the United States portion of the basin, snowpacks are generally lower than average. The BC River Forecast Center’s reported the West and East Kootenay Snow Basin Indices to be 105% and 111% of the 30-year period of record normal, respectively February 1 Bulletin. The U.S. Department of Agriculture’s Natural Resource Conservation Service (NRCS) is reporting lower percentages across the region, at 56% of the 30-year period of record normal in the Kootenai Basin. Maps produced by the NRCS are available here.

A follow up new release will be published once Kootenay Lake reaches its minimum elevation and when the Board declares the commencement of spring rise.

The Board is currently gathering input from the public and interested parties on potential changes to the regulation of Corra Linn Dam. This initial information gathering will inform a Plan of Study to analyze potential changes to the operation of the dam affecting water levels throughout the year. The Board is accepting input until March 1, 2026. You can submit your input directly to the contractor developing the Plan of Study at kootenaylakePlanOfStudy@gmail.com.

Quick Facts

  • The International Kootenay Lake Board of Control oversees the operation of Corra Linn Dam to manage water levels in Kootenay Lake.
  • This year’s board and public meetings are scheduled for the week of June 1st, 2026. Two public meetings will be held. The first public meeting will be held on June 2nd from 6:30-8pm PDT in Nelson, British Columbia, and the second will be held on June 3rd from 6:30-8pm PDT in Bonners Ferry, ID with a virtual option. Virtual registration will be available on the board website closer to the date here.
  • Last year’s board and public meetings were held on May 7, 2025 in Nelson, British Columbia. A recording of the public meeting is featured on the board website here, along with published minutes.
  • The web-based Kootenay Lake Visualization tool is available for the public to investigate Kootenay Lake conditions in dry, normal, and wet years. The link is here.
  • To contact the Board by email, click “Contact” under “Contact Us” at the bottom of the webpage here.
  • Stay in touch and subscribe to receive email news updates from the Kootenay Board.

Contacts

David Varner, Interim U.S. Secretary     mailto:David.C.Varner@usace.army.mil

Martin Suchy, Canadian Secretary        Martin.Suchy@ec.gc.ca

 

International Kootenay Lake Board of Control