High Flows and Fish Migration

It rained!! In 24 hours yesterday, the river flow (discharge measured at Winchester) increased from 6,000 cubic feet per second (cfs) to 25,000 cfs. The long-term (79 years) median flow is 3600 cfs for late December and the mean flow is 6,600 cfs. The highest flow recorded for today was 37,200 cfs in 1999. The lowest flow was 1040 cfs in 1977. The warmer temperatures during this rain event peaked just below 48 degrees, well above the 38 degrees observed a week ago. Winter steelhead (and a few largescale suckers) were migrating in good numbers the past few days. The fish are currently holding near the river edges or moving slowly in the lower velocity areas to conserve energy at times like this. It is normal winter steelhead behavior to start their long migration again as the higher flows start to decrease in between rainstorms.