As the spring freshet begins to swell local rivers and tributaries, representatives from both BC Hydro and the US Army Corps of Engineers are monitoring water levels in Lake Koocanusa and Kootenay Lake.
Steve Barton, with the U.S. Army Corps of Engineers, says there could be an above normal runoff, given that the snowpack in the East Kootenay was 120 per cent of normal as of March 1st.
“The snowpack conditions right now with the cold and relatively wet winter that we’ve had, snow conditions are above normal throughout the Kootenay basin, and therefore we’re expecting runoff conditions to be above normal as well,” Barton said.
“The reservoir is drawn down to a level that we believe is appropriate for the local runoff and to provide flood risk management both locally and for the Columbia system at large.”
While there hasn’t been any flooding threats in Cranbrook, Mark Creek has overflowed in some areas of Kimberley, while the Okanagan is dealing with some flooding in some communities.
“Runoff is just beginning,” said Barton. “We’re seeing some swollen rivers out there right now, so as we begin to reduce peak flows and manage flood risks, the reservoir will begin to refill.”
In the summer, Barton says he is expecting the Lake Koocanusa reservoir to be 5-10 feet below full capacity at 2,459 feet.
“The likelihood of being within the top 10 feet if not full itself is pretty good this year and then for the fish operations that are required, we will be drafting 10 feet from full by the end of August,” Barton said.
Sturgeon operations at the Libby Dam are tentatively planned to begin in the middle of May and officials are hoping to maximize the number of days that Kootenai River flows are above 30,000 cubic feet per second at Bonners Ferry.
Data from tagged spawning sturgeon indicated roughly a 20 per cent increase in the number of spawning sturgeon that migrated upstream from Bonners Ferry, according to the US Fish and Wildlife Service.
Additionally, on the American side of the border as well, the Kootenai River Habitat Restoration Project continues under the leadership of the Kootenai Tribe of Idaho, which is constructing islands, digging pools and creating pool-forming structures upstream from Bonners Ferry.
Darren Sherbot, BC Hydro Operations Planning, Manager, says levels out at Kootenay Lake are continually monitored and that the company is seeing levels similar to last year.
“The story for Kootenay Lake and Kootenay River this year is similar likelihood of flood risk to last year, which never materialized,” Sherbot said, “but again, with the high snowpack and the delayed spring, when it melts off, it’s going to melt off pretty quickly and we’re anticipating that and seeing that over the next three weeks.”
Factors such as temperatures, weather conditions and how rivers and waterways respond to those conditions determine how severe the runoff will be, said Barton.
“That will be the main driver of whether it comes off in a relatively slow, manageable way or whether it comes rushing off, which presents more of a management challenge,” said Barton.
Representatives from BC Hydro, the US Army Core of Engineers and the provincial government held a public information meeting in Wardner on Wednesday night.