Big Thompson River Fishing Guides

About the Big Thompson River

The Big Thompson is one of the Front Range’s defining rivers, and one of its most heavily used. It rises in Forest Canyon inside Rocky Mountain National Park, runs east through Moraine Park and Estes Park, and then drops through the Big Thompson Canyon in a steep twenty-five mile run to the plains at Loveland. US Highway 34 follows the canyon the whole way, which is why so many anglers fish it and why so much of it is roadside water. The canyon reach is the headline: pocket water, plunge pools and short runs between granite, fished hard from spring through fall.

Below Lake Estes the river is regulated, and the character of the flow reflects that rather than the snowpack alone. The upper canyon holds brown and rainbow trout in good numbers with brook trout in the tributaries and cutthroat and cuttbow higher up inside the park, and Colorado Parks and Wildlife manages a stretch of the canyon under special regulations that have built up a better size structure than the pressure would suggest. The river also carries the memory of two catastrophic floods, in 1976 and 2013, both of which rearranged the canyon and the fishery.

By the time it reaches the Loveland gauge the river has left the canyon and changed species. The plains reach runs warmer and slower through town and out toward the South Platte, holding largemouth and smallmouth bass, channel catfish, carp and suckers alongside the trout that drop down from above. That transition is the thing to understand before fishing it: the same river rewards a dry-dropper in the canyon and a streamer or a bait rod twenty minutes downstream. Anglers should decide which of these two rivers they came for before setting out, because the canyon and the plains reach reward entirely different tackle.

Access

Big Thompson Canyon - the US 34 corridor above Loveland, with a long series of pull-offs and the most productive trout water on the river.
Loveland - the city at the gauge reach, where the river leaves the canyon and the warmwater species take over.
Estes Park - the upstream town below Lake Estes, the head of the regulated canyon reach.
Rocky Mountain National Park - the headwaters in Moraine Park and Forest Canyon, with park regulations and a separate licence framework.
Viestenz-Smith Mountain Park - the Larimer County park in the lower canyon, giving developed public access and parking.
Narrows - the steep mid-canyon section, where the pocket water is best and the roadside parking is tightest.
River's Edge Natural Area - the Loveland open space along the lower river, with walkable frontage through town.

Seasons

Spring: runoff dominates the canyon and the river runs high and pushy, with the plains reach at Loveland fishing better than the upper water.
Summer: the main canyon season, with the regulated flow holding steady, good dry-fly fishing in the pocket water and heavy angling pressure along the highway.
Fall: the best weeks, as brown trout spawn, the crowds thin after Labor Day and cooler water brings the fish back onto the feed through the day.
Winter: low and cold with ice in the shaded canyon, though the regulated releases keep open water and the lower river stays fishable on mild days.