Cheesman Canyon
14 Day Forecast: Look for sporadic hatches of midges.
Effective Patterns: #20-22 Top Secret Midge, #20-22 Manhattan Midge, #20-22 Jujubaetis, #20-22 Top Secret Baetis, #20-24 Chocolate Foam Wing Emerger, #18 Micro Egg, #20-22 Red Larva, #20 Mercurry Blood Midge, #20 Flashback Mercury Black Beauty, #20 Buckskin, #20-22 Pat's Midge, #20-24 Griffith Gnat, #22 Mole Fly, and #22-24 Parachute Adams.
Measurements
Stream Conditions & 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 114 cfs below Cheesman Reservoir. We’re expecting another dry week so outflows remain a bit higher to supply the City’s needs. Cheesman Reservoir is at 86% capacity as of this morning. Considering all things, and the drought we’re experiencing, it could be much worse. I expect Denver Water to keep the outflows between 50 and the 100 cfs range for the majority of the winter in an effort to keep the lake as full as possible. Nothing is coming easy right now with the cold water temps, but anglers willing to work hard are bringing a few fish to hand. Target the deeper runs and slower pools with spider web thin tippets and tiny midges. The difference between catching fish and NOT, is fishing with a size 24 midge pupa instead of a 22. It’s to your advantage to cover lots of water as the trout wisen up quick in the slower water with repetitive casting. The best fishing is between 11 a.m. and 2:30 p.m. Revised 1/20/26