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River guide · Colorado

Fly Fishing the Big Thompson River

Below Olympus Dam at Estes Park, the Big Thompson cuts a tight canyon down to the plains, its cold, regulated flows sustaining a blue-ribbon tailwater fishery for wild brown and rainbow trout that commonly push 20 inches. Summer evenings draw crowds to the caddis hatch, but spring midge fishing and fall Baetis seasons belong to the patient angler willing to fish small flies with a light touch.

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When to fish

Year-round

Best months: year-round

  • Best

Midge: year-round. Blue-winged Olive / Baetis: March–May, Sept–Oct.

Today's conditions

Where to fish

Olympus Dam down to the Waltonia Bridge

U.S. Highway 34 runs alongside the river through Big Thompson Canyon, providing easy pull-offs and direct wade access along the approximately 9-mile catch-and-release section from Olympus Dam down to the Waltonia Bridge. No permit required; artificial flies and lures only in the C&R section.

The water

Tailwater

Key hatches

  • Midge
  • Blue-winged Olive / Baetis
  • Caddis
  • Pale Morning Dun
  • Stonefly
Hatch calendar

Conditions

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6-day forecast

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Forecast from the National Weather Service ↗

Key hatches

  • Midge (year-round)
  • Blue-winged Olive / Baetis (March–May, Sept–Oct)
  • Caddis (June–August, prime evenings)
  • Pale Morning Dun (summer)
  • Stonefly (June–July)
  • Terrestrials (July–September)

Fly shops near the Big Thompson River

Shops and guides that fish the Big Thompson River. See all 114 Colorado shops →

10 fly shops shownBig Thompson River at Estes Park

Species on this water

TroutSalmonSteelhead

Nearby towns

Estes ParkFort CollinsLongmont

Rivers nearby

Williams Fork RiverBlue RiverGore CreekSouth Platte River
From The Fly Bench

Tie the flies that work on the Big Thompson River

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Gear up on the Big Thompson River

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The flies that work on the Big Thompson River

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