The Blue River below Green Mountain Reservoir is a true winter tailwater. Cold, clear releases, steady flows, and trout that expect you to get everything right. This stretch does not give away free eats, but if you slow down and fish with intent, it will absolutely produce.

Updated: January 29, 2026

The Blue River below Green Mountain is holding in a stable winter tailwater pattern. Flows are steady, water clarity is excellent, and trout are holding deep along seams, inside bends, and slower walking-speed lanes. Feeding activity is subtle but dependable during short midday windows.

This week’s Blue River fly fishing report below Green Mountain emphasizes precision. Trout are present and feeding, but sloppy depth control or rushed drifts shut things down quickly.

(Real-time USGS data from site USGS-09057500)

Flow (CFS): ~120 cubic feet per second as of Jan 29, 2026 — a solid winter tailwater flow for this stretch

Water Temperature: Not reported in real-time, but typically upper 30s to low 40s °F this time of year based on local winter patterns and similar gauges

Air Temperature: Generally low 20s to mid-30s in the canyon corridor on clear days (weather patterns)

Clarity: Clear (tailwater below major reservoir, typical winter clarity)

Crowds: Light to moderate near the dam access and canyon trailheads

Best Window: 11:00 a.m. to 3:00 p.m. — midday warmth triggers more active feeding

Fishing Focus: Winter nymphing with midges, baetis, and mysis-style subsurface patterns

Expect hard overnight freezes and limited early sunlight. Calm, sunny afternoons fish best. Wind shuts down feeding quickly on this stretch.

Black Beauty #20–24

Top Secret Midge #20–22

Zebra Midge (black or red) #20–22

RS2 gray or black #20–22

Mysis Shrimp imitation #16–20

Mini Leech #12–14 (for deeper water)

Small and precise patterns win here — especially under winter conditions with low light and cold water.

• Indicator: Yarn or tight-line presentation
• Lead Fly: Small Pheasant Tail or WD-40 18 to 20
• Dropper: Zebra Midge or Black Beauty 20 to 22
• Weight: Light and precise, adjusted often
• Target Water: Inside bends, slow tailouts, and deep winter seams
  Pro Rig of the Week: Green Mountain Deep Slot Rig