Kootenay Lake 2024 Fall Levels and Winter Weather Outlook

Date

Maximum Kootenay Lake Levels

This fall, Kootenay Lake levels have been in compliance with the International Joint Commission (IJC) Order of Approval, which sets the maximum allowed water level. 

During the late summer, the IJC maximum water level was 1743.32 feet (531.36 meters) at Nelson, British Columbia, to allow farmers in the Kootenai Flats region to work their fields without an elevated water table. 

On September 1, 2024, the Kootenay Lake maximum water level switched from the Nelson gauge to the Queens Bay gauge for compliance measurements. 

The maximum lake level measured at the Queens Bay gauge is 1745.32 feet (531.97 meters) and will remain constant until January 7, 2025. Starting January 8, the maximum allowed water level will be slowly decreased to 1739.32 feet (530.14 meters) on April 1 to prepare for the spring snowmelt (Figure 1).

Figure 1: Kootenay Lake maximum lake elevations as defined by the IJC 1938 Order of Approval rule curve

Figure 1: Kootenay Lake maximum lake elevations as defined by the IJC 1938 Order of Approval rule curve 

Observed Kootenay Lake Levels

Kootenay Lake levels remained low throughout the start of fall (September and October) but have been increasing since the start of November. As of this writing, the Kootenay Lake at Queens Bay water level is at the 23rd percentile and trending up due to increased releases from Libby Dam upstream but remains below the historical mean for the period of record since the construction of Libby Dam in 1976. 

Figure 2: Top  graph - Kootenay Lake levels at Queens Bay (green) and Nelson (orange) and the IJC 1938 Order of Approval Rule Curve for 2022 (red). Bottom graph - Lake outflow controlled by Corra Linn (pink) or Grohman Narrows (purple). Credit: FortisBC (data) and Environment and Climate Change Canada (plot), 2024

Figure 2: Top graph - Kootenay Lake levels at Queens Bay (green) and Nelson (orange) and the IJC 1938 Order of Approval Rule Curve for 2022 (red). Bottom graph - Lake outflow controlled by Corra Linn (pink) or Grohman Narrows (purple). Credit: FortisBC (data) and Environment and Climate Change Canada (plot), 2024 

Snowpack and Winter Forecasts

Since October 1, snow accumulation is slightly above average. The developing snowpack can be seen below, in an image taken November 12 at Redfish Creek, British Columbia. As of November 19, Redfish Creek has 334 mm snow-water equivalent (SWE), which is above the 75th percentile for the period of record (2001-2023).

Figure 3: Redfish Creek (2D14P) snow pillow station in the Kootenay River basin. Credit: BC Ministry of Environment and Climate Strategy

Figure 3: Redfish Creek (2D14P) snow pillow station in the Kootenay River basin. Credit: BC Ministry of Environment and Climate Strategy

Long-term forecasts and indicators offer insight into potential winter weather. Forecasts show weak La Niña conditions, which are typically associated with cooler and wetter weather in the region.

Predicted temperatures in December, January and February for the region are unclear; Canadian long-term weather forecasts indicate average temperatures, whereas US long-term weather forecasts indicate below-average temperatures. Both Canadian and US forecasts predict a wetter-than-normal precipitation outlook for December, January and February. 

Figure 4: Canadian (left) and US (right) Seasonal Precipitation Outlook. Credit: Environment and Climate Change Canada, October 31, 2024; National Oceanic and Atmospheric Administration, October 17, 2024 (right)

Figure 4: Canadian (left) and US (right) Seasonal Precipitation Outlook. Credit: Environment and Climate Change Canada, October 31, 2024; National Oceanic and Atmospheric Administration, October 17, 2024 (right)

Quick Facts:

  • Fortis BC owns and operates Corra Linn Dam, which determines Kootenay Lake elevations. Current information on lake levels and flows can be found on the Fortis BC website.
  • This year’s board and public meetings were held May 22 in Bonners Ferry, Idaho. A recording of the public meeting is available on Vimeo
  • Next year’s public meeting is set for May 7, 2025, in Nelson, British Columbia.
  • 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.
  • Sign up to receive email news updates from the Kootenay Board.

 

Contacts

Sonja Michelsen, US Secretary to the IKLBC

Martin Suchy, Canadian Secretary to the IKLBC

International Kootenay Lake Board of Control