Notice of Dry Conditions at Kootenay Lake
Due to low snowfall throughout the winter of 2023/2024, Kootenay Lake water levels are very low for this time of year. However, lake level operations remain in compliance with the International Joint Commission’s (IJC) 1938 Order of Approval.
The Kootenay Lake water level on August 19 is the lowest in the 1976-present comparison period. The 1976-2023 comparison period is used because Libby Dam in Montana, which influences water inflow and levels at Kootenay Lake, was completed in 1975.
On August 19, Kootenay Lake at Nelson was at 1741.91 feet (530.93 meters) and Kootenay Lake at Queens Bay was 1742.39 feet (531.08 meters). The calendar year peak at Queen’s Bay was on June 4 at 1745.67 feet (532.08 meters), which is below normal at the 29th historical percentile. A graph of the 2024 water levels and Queens Bay historical average and percentiles can be seen below:
Figure 1: Kootenay Lake levels at Queens Bay, British Columbia (green), and Nelson, British Columbia (orange), lake outflow control by Corra Linn (pink) or Grohman Narrows (purple), and the International Joint Commission 1938 Order of Approval Rule Curve for 2024 (red). Credit: FortisBC (data) and Environment and Climate Change Canada (plot), 2024
The total volume of water that entered Kootenay Lake during the April 1 through July 31 runoff period was the fifth-lowest volume observed between 1999-2024. (Figure 2). Inflow data provided by Fortis BC is only available since 1999.
Figure 2. Kootenay Lake April 1 to July 31 cumulative inflows (blue). Credit: FortisBC (data) and Environment and Climate Change Canada (plot), 2024
The graphs below show a comparison between 2024 and 2023 inflows and lake levels.
Figure 3: 2023, 2024 and mean values for Kootenay Lake inflow and level. Credit: FortisBC (data) and Environment and Climate Change Canada (plot), 2024
Kootenay Lake’s compliance with the 1938 Order is not impacted by drought conditions. The 1938 Order of Approval for Kootenay Lake sets allowed maximum lake elevations throughout the year. There are no lower elevation bounds.
After mountain snowmelt dwindles in the late spring, Kootenay Lake is required to be lowered until it reaches 1743.32 feet (531.36 meters) at the Nelson gage. After that point, Kootenay Lake levels (as measured at Nelson) must be kept below 1743.32 feet until August 31.
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 on May 22. A recording of the public meeting is available on Vimeo.
- 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:
Katryna Slimmon, Canadian Secretary to the IKLBC
Sonja Michelsen, US Secretary to the IKLBC