By: Korie Marshall
Boaters and water enthusiasts take note – Kinbasket Reservoir was much higher than usual over the winter, but it is expected to be lower than usual this summer.
Mild weather this past winter contributed to the higher than usual levels, said BC Hydro staff during a regular operations update conference call on June 16th. Precipitation that usually falls as snow fell as rain, which meant it accumulated in the reservoir quicker, said Darren Sherbot and Peter McCann with the System Optimization department. And because it was mild, there was less demand to generate power at Mica, so much of that water was held back.
But this spring, it’s been unusually warm and dry throughout the Columbia Basin and water levels are expected to be lower than normal this summer.
This is the third driest year on record since 1960 in the Columbia Basin, according to snow pack and water supply records. It’s not as dry here in the northern reaches of the basin, but the precipitation throughout is currently only 68 per cent of normal. Only 1997 and 2001 were dryer.
That means that dry-year provisions in the Columbia River Treaty have kicked in, which includes a “proportional draft.” That means that all reservoirs on the Columbia, either in Canada or in the US, have to release a bit extra water. It’s not unusual for the proportional draft provisions to kick in, says Sherbot, but it is unusual for it to happen so early in the season.
Sherbot and McCann also explained that there is a “fish benefit account”, which basically sees BC Hydro collect one million acre feet of water in their reservoirs (usually in January) and release it in July to help keep flow higher for fish values in the US. This year, the US wanted it released in May and June, but BC Hydro was able to negotiate that some, to both help the fish on the US side and to keep levels in the Arrow Lakes higher.
BC Hydro says they ran Mica and Revelstoke generators harder than normal from March to May, both for system requirements and to help support water levels in the Arrow Lakes, which see a lot of recreation use. Arrow will still be much lower than normal this summer, and BC Hydro will be generating at Mica to help keep Arrow higher, which also means lower levels for Kinbasket. It is currently expected to be 5-15 feet below normal full pool, which is 2475 feet (754.4 m). According to the current forecast, it is expected to peak in mid July, but McCann points out that the forecast is less reliable the further into the future.
Last year Kinbasket peaked at 2473.7 feet on Nov. 9th. Two years ago the reservoir was surcharged (brought above the normal full pool level) in September by about one foot. BC Hydro currently estimates Kinbasket will reach it’s maximum for the year in July and August, at between 2460 and 2460 feet.