Osoyoos Lake was calm overnight, holding at around 916.42 feet.
But prognosticators fear warm weather entering BC today could restart a snowpack melt engine that will push more water into the province’s swollen creeks, streams and rivers — and eventually into Osoyoos Lake.
“Osoyoos lake level is currently at 916 ft. which exceeds previous high levels for the month of May seen in 1972 (915.79 ft. on May 31, 1972) and is expected to keep climbing through the weekend (May 12-13),” reports the International Osoyoos Lake Board of Control in a release.
“The increasing water levels on Osoyoos Lake are largely due to extremely high flow rates on the Similkameen River, which flows into the Okanogan River downstream of Osoyoos Lake, impeding outflow of water from Osoyoos Lake (backwater effect) and coupled with high inflow into Osoyoos Lake from the upstream Okanagan River.
The Board said it expects the lake will reach a peak level just as “the flow rate on the Similkameen River begins to drop and the backwater effect on Osoyoos Lake discharge eases off.”
“The maximum water level that will be reached on Osoyoos Lake during the 2018 freshet is difficult to predict due to its dependence on changing weather conditions and resulting rates of snowmelt,” the Board said.
Currently in Osoyoos:
- Forty-seven properties on Harbour Key Drive and Solana Key have been evacuated — 24 more properties added laste yesterday to an intial evacuation order issued May 10.
- Five other properties on Cottonwood Drive were also evacuated, as was a single property on Kingfisher Drive.
- Harbour Key Drive is closed to public traffic;
- Spartan Drive is closed at the marina;
- Vehicle traffic entering Lakeshore Drive is restricted as the area is being identified as local traffic only.
The use of sump pumps to remove water from flood basements is prohibited. The Town is also ordering that homes or businesses with water is the basement cover their floor drains and use other methods of draining their flood water outside the home.
“The act of causing this water to enter the sewer system in current conditions is causing pump infrastructure to function beyond capacity, which may result in a breakdown of the Town sewer management system,” the Town said.
Contrary to other discussion in the community, the provincial Ministry of Transportation and Infrastructure has no plans to close the Osoyoos Lake bridge, according to the Acting Mayor Mike Campol and CAO Barry Romanko.
Similarly, there is no truth to the rumor US officials have closed Zosel Dam — at the south end of Osoyoos Lake — to protect properties in Washington State.
“The flow control gates at Zosel Dam have been fully open since March 26, allowing the dam to pass as much water as possible during this high water period,” the control board is reporting.
The maximum level of Osoyoos Lake recorded since regulation through the use of the Zosel Dam was 917.11 feet in June 1972.
Yesterday, Shaun Reimer, Emergency Management BC’s section head of Public Safety and Protection in the Thompson Okanagan, said he believes the lake will exceed 917 feet but added how far it could rise above that is somewhat up to Mother Nature.
Environment Canada is forecasting temperatures to soar above 30C beginning Sunday before finally cooling again later in the week. A mix of sun and cloud could bring more rain beginning Thursday.
The forecast is similar for other parts of the province that impact water flow to Osoyoos Lake.
Meanwhile, in the neighbouring Regional District of Kootenay-Boundary (RDKB), evacuation orders are in place for more than 2,500 properties as flood waters have swamped the communities of Grand Forks, Christina Lake and Midway.
“Record high water levels in the West Kettle, Kettle and Granby rivers overnight have flooded hundreds of properties, knocked out power in a large area of Grand Forks and trapped an unknown number of residents in their homes in Grand Forks,” reported RDKB’s Frances Maika.