Beaverhead River
The Beaverhead River is a tailwater fishery below Clark Canyon Reservoir and flows for approximately 70 miles.
This iconic Montana fly fishing stream is world-renowned for producing large Rainbow and Brown Trout. Rainbow Trout regularly approach 20” in length and Brown Trout over 24” are not uncommon.
The narrow, windy river will challenge the skills of the most experienced angler with casting dries, nymphs, and streamers in tight quarters where precision is key.
Anglers fishing the Beaverhead River are there for the lure of big trout; visions of solitude and breathtaking scenery take a back seat to the big trout of this legendary Montana fishing destination.
Beaverhead River Sections
Clark Canyon Dam to Barrets
The upper section of the Beaverhead River is the most popular spot for anglers, especially between Clark Canyon Dam and Henneberry Fishing Access Site.
The flow of the river changes depending on downstream irrigation demands. The best time for floating is when Clark Canyon releases range between 500 and 1000 CFS. Anglers who prefer wading typically fish the upper Beaverhead River when flows are near 300 CFS. The amount of water in the river is a crucial factor that affects fly fishing in Montana on the Beaverhead River.
Technical fly fishing using tandem nymph rigs with heavy weights added to keep the flies near the bottom is the standard technique for fishing the Beaverhead River. Although excellent dry fly and streamer fly fishing can be experienced as well.
Barret's Dam to Dillon, MT
Barrett's Diversion Dam is situated 18 miles downstream of Clark Canyon Dam and marks the boundary between the upper and lower river sections. Approximately 50% of the water from the Beaverhead is diverted here into irrigation ditches that run through the arid valley near Dillon.
The river snakes its way through vast stretches of private land, and limited public access is available.
Wading anglers can avoid the floating pressure on the upper river and more easily move up and down the river while staying below the high water mark. Although the trout numbers are lower here than in the upper river, advanced anglers are drawn to this stretch by the big Brown Trout and the excellant dry fly fishing opportunities it offers.
Dillon MT to Twin Bridges
Downstream from Dillon, Trout populations are smaller than in the upper river above Barret’s Diversion Dam. Public access is difficult and limited along this stretch as well.
The river moves slowly during the summer months and quickly warms during the long days of June and July. Hoot Owl restrictions and complete fishing closures are commonly implemented in July and August.
The adventurous angler can find some large Brown Trout during the summer months, but they are far and few between. Small rafts or canoes that are easily maneuvered through long sections of slow-moving water are recommended versus traditional drift boats when fly fishing the lower Beaverhead River.
Fishing Conditions Through the Seasons
April - May
Blue-winged olive and Midge hatches dominate the early season surface activity on the upper river during the spring. Warm April days bring good numbers of trout to the surface during Caddis hatches along the river near Dillon.
The upper stretch between Clark Canyon Dam and Pipe Organ Bridge opens on the third Saturday in May. Anglers fishing the Beaverhead River on “opening weekend” endure crowded conditions with the hopes of hooking into trophy trout before they become wary of heavy angling pressure as summer approaches.
June - July
Beaverhead River fly fishing is at its best during the early summer months when water is plentiful, and hatches are thick. Caddis, PMD, and Yellow Sally activity stirs the river’s trout from deep pools and undercut bank lies into skinny riffles and foam eddies.
While nymph fishing is the standard when targeting large trout along the upper river, rising fish can be found along the willows and tucked tight to the bank in heavy cover. Streamer fly fishing while floating the Beaverhead River is an exciting and challenging endeavor for skilled anglers fishing between Barrett’s Dam and Dillon.
August - September
Beaverhead River flows vary yearly and are dependent on the previous winter’s snowpack and downstream irrigation demands. Low streamflow and warm water is typical for the sections downstream of Barrett’s Diversion Dam.
The trout on the upper river are highly educated by August, selectively feeding on well-presented small nymphs as hatches diminish. Hoppers and Craneflies will bring the unexpected explosive strike from a large fish hiding deep within the bankside willows. Streamer fly fishing improves with cooling water temperatures as autumn arrives in September.
October - March
Clark Canyon Reservoir levels are often very low by the end of the summer because of heavy irrigation demands from the vast agricultural ranches near Dillon and Twin Bridges. Beaverhead River flows are typically severely reduced by late summer as irrigation wanes and reservoir managers begin to conserve water for the following season.
As of 2024, most of the Beaverhead River closes to fishing from October 1 through March 31. Anglers fly fishing in Montana should always consult the current fishing regulations before fishing in a new area, especially the Beaverhead River.
Beverhead River Fly Box Essentials
Beaverhead River Fly Fishing Trips
With over 30 years of experience fly fishing the Beaverhead River, we are excited to now include this premier Montana fly fishing river in our operation beginning in 2024.
Float the upper Beaverhead River with our Bozeman fly fishing guides during the peak season in June and July. Late summer and early fall options are available and dependent on water conditions.
Beaverhead River fishing trips are recommended for anglers with intermediate to advanced fly fishing skills. Beaverhead River trip rates for 2024 are $725 per day for 1-2 anglers; reservations can be placed via e-mail or by calling us at 1-406-468-5019.
Montana Fish of the Beaverhead River
