The Blue River below Green Mountain Reservoir is a peaceful, productive tailwater fishery, perfect for late fall fishing. With flows consistent around 75-100 CFS, this section of the Blue River offers steady, clear water and cooler temperatures that keep the trout active during midday hours. The trout are settling into winter patterns, which means a mix of subtle nymph presentations and occasional surface action during midge and BWO hatches.
For anglers seeking solitude and larger fish, this area is ideal. The deeper pools and slower runs make it a rewarding experience for nymph and streamer enthusiasts, especially when targeting rainbows and browns as they bulk up for the colder months. Light presentations and stealthy approaches will pay off in this beautiful, quiet stretch of the river.
Source: Colorado Division of Natural Resources River Flow Station Reprort
| Month | Primary Hatches | Effective Patterns |
|---|---|---|
| March | Midges, Baetis (BWO) | Zebra Midges (#20-24), Blue Wing Olive (#18-22) |
| April | Midges, Baetis, Caddis | Black Beauty (#18-22), Elk Hair Caddis (#16-18) |
| May | Baetis, Caddis, Stoneflies | Blue Wing Olive (#18-20), Pat’s Rubber Legs (#10-12) |
| June | Caddis, PMDs | Elk Hair Caddis (#16), PMD Comparadun (#16-18) |
| July | Caddis, Yellow Sallies | Yellow Sally (#14-16), PMD Emerger (#18-20) |
| August | Tricos, Caddis, Terrestrials | Trico Spinner (#22-24), Parachute Hopper (#10-12) |
| September | BWOs, Midges, Caddis | BWO Parachute (#18-22), Black Ant (#18-20) |
| October | BWOs, Midges | Blue Wing Olive (#18-22), Zebra Midge (#20-24) |
| November | BWOs, Midges | BWO Emerger (#18-22), Black Beauty (#20-24) |
| December - February | Midges | Griffith’s Gnat (#20-24), WD-40 (#18-22) |
Seasonal Tip
Focus on midday fishing for the most active trout, as the colder mornings often keep them subdued until temperatures rise.
Dry Fly
Small BWOs can be productive during mid-morning to early afternoon, especially in slower sections of the river. A well-placed Blue Wing Olive can tempt even the pickiest trout to the surface.
Nymphing
A two-fly nymph rig with a Pheasant Tail and Zebra Midge is your go-to here. Work the seams, riffles, and tails of pools, adjusting weight for the river’s slower flows.
Streamer Fishing
For targeting larger trout, use an Olive Sculpzilla or similar streamer pattern. Keep retrieves slow, focusing on deeper sections and areas with structure.
The Blue River below Green Mountain Reservoir is a catch-and-release fishery. Barbless hooks are recommended to reduce stress on fish. Always respect private property along the river, using designated access points and practicing good river etiquette. A valid Colorado fishing license is required, and anglers are encouraged to follow local fishing regulations to preserve this tailwater fishery.