Update on Kootenay Lake Water Levels

The International Kootenay Lake Board of Control (IKLBC) reports that Kootenay Lake operations this spring and summer have complied with the International Joint Commission’s (IJC) 1938 Order of Approval which sets the maximum lake level through operation of the Corra Linn Dam. Kootenay Lake levels peaked in mid-June and have since decreased to the current level of 1744.1 feet at Queens Bay.

The total volume of water that flows into Kootenay Lake over the summer primarily depends on the previous winter’s snowpack.  Redfish Creek (West Kootenay) and Moyie Mountain (East Kootenay) snow pillow stations saw below-normal snow accumulation throughout the 2024-2025 winter with snowmelt beginning earlier than typical.  The Moyie Mountain snow pillow began melting in late April, while the Redfish Creek snow pillow did not begin melting in earnest until late May (Figure 1).

Inflows to Kootenay Lake peaked on May 30. The lake reached its 2025 peak elevation of 1746.32 feet (532.28 meters) on June 15 at Queens Bay, British Columbia. The peak level was lower than average but occurred at the typical time of year.

Following the peak, the Kootenay Lake level decreased throughout the rest of June, as expected. During the freshet, lake releases were limited by the natural constriction at Grohman Narrows and not Corra Linn operations (shown in the purple line of Figure 1).  To learn more about how lake levels are affected by the Grohman Narrows, visit the Board’s  web-based Kootenay Lake Visualization Tool.

Figure 1: 2025 data from the Redfish Creek and Moyie Mountain snow pillow station. Orange lines illustrate the Snow Water Equivalent (SWE) for the current year. Black line represents the median SWE for the station’s periods of record. Credit: BC River Forecast Center (data) and Environment and Climate Change Canada (plot), 2025

Figure 2: Kootenay Lake levels at Queens Bay (green) and Nelson (orange), lake outflow control by Corra Linn (pink) 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), 2025

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 were held on May 7, 2025 in Nelson, BC. A recording of the public meeting is available here.
• The web-based Kootenay Lake Visualization Tool is available for the public to investigate Kootenay Lake conditions in dry, normal and wet years.
• You may contact the board through the Contact form on its website.
• Stay in touch and subscribe to receive email news updates from the Kootenay Board.

Contacts

Sonja Michelsen, U.S. Secretary

Martin Suchy, Canadian Secretary

International Kootenay Lake Board of Control

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