Water levels in the Arrow Lakes Reservoir have reached what is likely the high water mark for 2025.
On June 19, the reservoir reached an elevation of 436.2 metres when measured at the Fauquier gauge. That level is 3.9 metres below full.
From here on, BC Hydro expects the reservoir level to decrease.
The latest minimum elevation of 423.03 metres was reached on Jan. 31.
In 2024, Arrow Lakes reached a peak elevation of 437 metres on June 28, almost a meter higher than this year's peak. In 2023, the high was 439.06.
The water licence for the reservoir allows a fluctuation from a low of 419.9 metres to a high of 440.1 metres.
BC Hydro is forecasting Columbia Basin run-off for April to September to be 79 per cent of normal.
For the same period in 2024, the observed run-off in Canada was 75 per cent of normal and the Columbia Basin as a whole was 74 per cent of normal.
In recent years, low water levels in late summer and fall have been of particular concern. Beyond the frustration of waterfront property owners and hindrances to recreational uses, impacts to fish have been observed.
In September of 2024, BC Hydro crews began monitoring fish as water levels dropped after a hot and dry summer.
The situation was worse in 2023 when many stranding pools were identified. That year, over 530 kilometres of shoreline were assessed by BC Hydro to identify pools and focus ground surveys and salvage efforts. That research was used in 2024 to inform fish monitoring and salvage decisions.
The elevation of reservoirs is influenced by snowpack, inflow levels, weather patterns and other factors such as load requirements, so this year's summer and fall water levels are still to be determined.
BC Hydro cautions that near and long-term forecasting is inherently uncertain due to the unpredictability of future events and conditions.
