Colorado River
14 Day Forecast: Look for hatches of midges, yellow sallies, caddisflies and pale morning duns.
Effective Patterns: #20-22 Jujubaetis, #20 Mercury Midge, #20-22 Top Secret Baetis, #18-20 Mercury Pheasant Tail, #20-22 Chocolate Foam Wing Emerger, #18 Micro San Juan Worm, #16 Hot Tail Flash Egg, #18-20 Buckskin, #20-22 Sparkle Wing RS 2, #20 Sparkle Dun, #20 Parachut Adams, #22 Pat's MIdge, and #20-22 Griffith Gnat.
Measurements
Stream Report, Effective Patterns, & Expert Information for Fly Fishing the Colorado River
The Colorado River begins its journey in Rocky Mountain National Park and heads west offering anglers several opportunities to sample this great stream. Near the small community of Granby is the confluence of the Fraser River. At this point the river is a meandering, meadow stream flowing through lush ranchland and the river remains this way until it hit Byers Canyon. Byers Canyon is only about 3/4 mile long and this section is tough to negotiate, especially during higher flows. Below Byers Canyon the river is “as good as it gets” with many access points including Paul Gilbert, Lone Buck, Kemp-Breeze, Sun Set Ranch, Powers Unit, Reeder Creek and the Pump House to Radium stretch. The Colorado is lined with cottonwood trees and willows and is a dry fly paradise. Anglers can expect to catch a mixed bag of both browns and rainbows. The regulations in this area are flies and lures only and all fish must be returned to the water immediately.
Fishing the Colorado River should be on everyone's bucket list. Whether you're a walk/wade fisherman or prefer float-fishing, this river has something for everyone!
Tips & Other Information:
Flows are 357 cfs currently on the Colorado River near Parshall. Below Kreemmling, the Colorado is 701 cfs with 256 cfs being released from Green Mountain Reservoir. Green Mountain Reservoir is the lowest I’ve ever seen it. It is down to 20 percent capacity. This is getting scary now! Anglers should prepare themselves for hatches of yellow sallies, caddisflies and pale morning duns. Start early and quit early with the low water around the Parshall area. Williams Fork Reservoir is at 33% capacity which is concerning as well. Inflows are now down to 6 cfs! Don’t forget your long sleeved shirts, a buff and sun gloves, and a can of Deep Woods off! Keep and eye on water temperatures and quit fishing if they hit 67 degrees. Revised 8/18/26