Regional News

Osoyoos Lake Level Rising During Spring Snowmelt

May 11, 2018

In compliance with the terms of the International Joint Commission (IJC) water management Order for Osoyoos Lake implemented by the International Osoyoos Lake Board of Control, the gates at Zosel Dam have been fully open since March 26 to allow for maximum outflow from Osoyoos Lake during melting of the snowpack in the Okanagan Basin.

As of May 1, the Okanagan Basin snowpack reached 206% percent of normal this Spring. Inflow to Osoyoos Lake from the Okanagan River is largely controlled by releases from Okanagan Lake Dam, which are anticipated to remain above normal due to high projected inflows to Okanagan Lake.

Given current conditions, lake level is no longer controlled by Zosel Dam, but depends on both inflow to and outflow from Osoyoos Lake. At this point, a larger part of the lake level rise is attributable to a backwater effect from high flow on the Similkameen River, which restricts outflow from Osoyoos Lake.