Cheesman Canyon
14 Day Forecast: Look for hatches of midges, pale morning duns, and blue-winged olives.
Effective Patterns: #20-22 Top Secret Midge, #20-22 Manhattan Midge, #20-22 Jujubaetis, #20-22 Top Secret Baetis, #20-22 Chocolate Foam Wing Emerger, #18 Micro San Juan Worm, #20-22 Red Larva, #20 Mercurry Blood Midge, #20-22 Flashback Mercury Black Beauty, #18-20 Buckskin, #18-20 Sparkle Dun (BWO), #22-24 CDC Biot Trico Comparadun, #18 Sparkle Dun(PMD) #14-16 Elk Hair Caddis, #10 Amy's Ant, #20-24 Griffith Gnat, #18-22 Mole Fly, and #20-22 Parachute Adams.
Measurements
Stream Tips from Pat Dorsey for Fly Fishing Cheesman Canyon in Colorado
The picturesque boulder-filled Cheesman Canyon portion of the South Platte River is considered by many one of the most pristine fisheries in the world. This area, often times simply referred to, as “the Canyon” is an experience you’ll never forget. It’s the perfect scenario, magnificent beauty in combination with great fly fishing.
The South Platte River carves its way through a granite canyon lined with ponderosa pines, willows, fallen tree trunks, and various other assorted ground foliages. Boulders as big as Volkswagens Beetles create structure for the super-selective trout residing in the river. Mule Deer, Black Bear, Raccoons, Mountain Lyons, and Bald Eagles all add to the experience. Anglers can expect to catch mostly large rainbows supplemented with a few nice brown trout. The aforementioned “canyon” is as technical as they get, and if you can catch trout here, you can catch them anywhere in the world. This three-mile section is primarily a nymphing fishery requiring tiny midge and mayfly imitations with fine 5 and 6X tippets. Ideal flows for Cheesman Canyon are between 250 and 400 cfs. The regulations are flies and lures only. All fish must be returned to the water immediately.
Cheesman Canyon is one of the best tailwaters in the country. There's a common belief among "canyon regulars" that if you can catch fish on the South Platte River, you can fool fish anywhere in the world. There's no substitution for good technique in Cheesman Canyon.
Tips & Other Information:
Outflows are currently 1053 cfs below Cheesman Reservoir. Class is back in session so bring your A-game. Cheesman Reservoir is currently at 67% capacity as of this morning. The lake is receeding fast because the inflows are only 84 cfs. Outflows are projected to stay around 100 cfs for the next two months. The hatches have been light but I am seeing a few PMD’s and Pseudocloeons. The morning midge-bite is the best part of the day. Midge larvae (Mercury Midge, pale-olive larva, etc.) have been my top producers as of late. Water temps are reaching the upper 50’s later in the afternoon. Revised 9/01/26