BC Hydro has released its latest forecast for the Lower Columbia reservoir levels, providing key updates for government officials, media, and the public.
These forecasts, which help manage water resources across the Columbia Basin, are subject to change due to weather patterns, energy demands, and treaty obligations.
The latest update shows fluctuations in water levels across major reservoirs.
- Arrow Lakes Reservoir: Currently at 425 metres (1393 feet), the water level is expected to rise to 426.1 metres (1398 feet) by Feb. 14, a 1.4-metre (4.5-foot) increase over the next week.
- Kootenay Lake: Forecasted to experience a slight drop of 0.1 metres (0.3 feet), reaching 531 metres (1743 feet) by Feb. 14.
- Duncan Reservoir: Currently at 557 metres (1828 feet), the water level is projected to drop by 1.4 metres (4.7 feet), reaching 556 metres (1823 feet) over the next seven days.
Discharge rates remain a critical factor in managing reservoir levels and energy production.
At Birchbank, the Columbia River's level is primarily influenced by discharges from Hugh Keenleyside Dam (Arrow Lakes) and Kootenay River flows from Corra Linn Dam.
Rapid changes in dam operations, particularly at Keenleyside, can cause noticeable fluctuations in water levels at Birchbank.
The April to September 2025 runoff forecast for the Columbia Basin at The Dalles, Oregon, is projected at 85 per cent of normal, showing an improvement from 74 per cent of normal in 2024.
Reservoir elevations are influenced by various factors, including snowpack levels, inflows, weather conditions, and power demands.
Reservoir trends and historical context
- Arrow Lakes Reservoir: Measured at 425 metres (1393 feet) at Fauquier on Feb. 7, it dropped 1.34 metres (4.4 feet) over the past week. The reservoir is forecast to rise to 428 metres (1402 feet) by the end of February. The highest recent level was 437 metres (1433 feet) on June 28, 2024, while the lowest was 423 metres (1388 feet) on Jan. 31, 2025.
- Duncan Reservoir: Measured at 557 metres (1829 feet) at Duncan Dam, the reservoir dropped 1.05 metres (3.4 feet) over the past week and is expected to decrease further to 553 metres (1814 feet) by the end of February. The highest recent level was 573 metres (1879 feet) on August 4, 2024, with the lowest recorded at 547.30 metres (1796 feet) on April 26, 2024.
With changing weather patterns and water demands, BC Hydro continuously monitors conditions, providing accurate updates for stakeholders across the Columbia Basin.
