After reaching a peak Wednesday morning, water levels on Osoyoos Lake have started a slow decline.
Levels reached a peak of 914.19 ft. at 2:30 a.m. on May 15 and stayed at that level through much of the morning.
By afternoon, Wednesday, the lake level made a slight decline, reaching 914.12 ft. at 11 p.m.
The water level has continued to drop Thursday, and as of 10 a.m. is at 914.04 ft. – still very high for this time of year, but moving in the right direction.
The change is more dramatic on the Similkameen River measured near Nighthawk, WA, which is a predictor of rises and falls on Osoyoos Lake.
After reaching a peak discharge of 20,600 cubic ft. per second at 6:15 p.m. Monday, May 13, levels began dropping at 9:15 p.m. Monday. As of 10 a.m. Thursday, volume has fallen to 13,800. This is the lowest level since May 8.
Although the Similkameen River joins the Okanogan River below the Zosel Dam at Oroville, WA, its flow determines whether water can leave Osoyoos Lake when levels are high. When water is high on the Similkameen, it backs up at the dam, preventing water from leaving the lake.
