Big Thompson River

Fishing Report

Big Thompson River

Technical dry-fly fishing in a Gold Medal canyon — updated weekly with current flows, hatch activity, and the best patterns for the Big Thompson.

Current Conditions

Updated Weekly

Big Thompson River conditions are heavily influenced by releases from Lake Estes and seasonal runoff through the canyon. Flow data is available from the USGS gauge at the canyon mouth. Check conditions before making the drive, especially during spring runoff when clarity and levels can change quickly.

Big Thompson Hatch Chart

MonthPrimary Bugs / Pattern
January

Midges

Zebra Midges, Mercury Midges, Black Beauties

February

Midges, early BWOs

RS2s, Zebra Midges, Baetis nymphs

March

BWOs, midges

Sparkle Dun BWO, RS2, Griffith's Gnat

April

BWOs, midges, early caddis

Parachute BWO, Copper John, Pheasant Tail, RS2

May

Caddis, BWOs, early PMDs

X-Caddis, Elk Hair Caddis, PMD Cripple, Hare's Ear

June

Caddis, PMDs, runoff dependent

Elk Hair Caddis, PMD Sparkle Dun, caddis pupae

July

PMDs, caddis, terrestrials begin

PMD Cripple, Elk Hair Caddis, hopper-dropper rigs

August

Hoppers, ants, beetles, caddis

Dave's Hopper, black foam beetle, Elk Hair Caddis

September

Caddis, BWOs returning, terrestrials

X-Caddis, RS2, hopper patterns, Parachute Adams

October

BWOs, midges

Sparkle Dun BWO, RS2, Copper John, Zebra Midge

November

Midges, occasional BWOs

Zebra Midges, RS2s, Black Beauties

December

Midges

Zebra Midges, Mercury Midges, WD-40s

River Overview

The Big Thompson River flows east out of Estes Park through a dramatic canyon before reaching the plains near Loveland. Known for technical dry-fly fishing and well-educated trout, the Big Thompson rewards patient, precise anglers with access to some of the best trout water in Colorado.

The river's Gold Medal designation covers the stretch from Lake Estes to Drake, a section prized for its consistent tailwater flows, strong wild trout populations, and diversity of water types. Anglers can expect everything from flat, glassy pools demanding fine tippet and drag-free presentations to fast pocket water where a high-stick nymph technique comes into its own.

Brown and rainbow trout are the dominant species, with fish in the 12–18 inch range common and occasional larger browns holding in the deeper runs. The trout in the Gold Medal section are among the most pressured in Northern Colorado, which is what makes fooling them so satisfying.

Access in the canyon is limited compared to the Poudre River — most of the corridor is private — making it important to know the public access points before heading out.

Access Points

Below Lake Estes

The stretch immediately below the Estes Park dam is accessible and holds consistent fish year-round thanks to regulated tailwater releases. Good for nymphing and early-season BWO hatches.

Viestenz-Smith Mountain Park (Loveland)

An excellent Larimer County park with strong wade access and a long stretch of fishable water. One of the most reliable public access points on the lower canyon, with parking and restrooms.

Drake / Highway 34 Pullouts

Several small pullouts along Hwy 34 and County Road 43 near Drake give access to mid-canyon water that sees less pressure than the highway-adjacent sections closer to Loveland.

Glen Haven / County Road 43

Mid-canyon access with excellent pocket water and deeper holding runs. Less traffic than the main highway pullouts and worth the extra navigation to find good water.

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