The Clark Fork River is Montana largest river system and one of the most remarkable ecological recovery stories in American conservation history. Over a century ago, copper mining contamination from Butte devastated the river, eliminating trout populations across 120 miles of water. Today, following decades of cleanup and restoration, the Clark Fork has returned to health — hosting strong populations of wild rainbow, brown, and westslope cutthroat trout through its 310-mile journey from its headwaters near Warm Springs to its confluence with Lake Pend Oreille in Idaho.
The most productive and accessible section for fly fishers runs from Clinton to Missoula, where the Clark Fork receives contributions from Rock Creek, the Blackfoot River, and the Bitterroot River — all world-class tributaries that push cold, clear water into the main stem. This section transitions from mountainous, forested terrain into the wider, deeper river that meanders through Missoula. The watershed encompasses over 14 million acres, and the river system — with its 28,000 miles of streams and tributaries — supports a richly complex ecosystem.
Wading the Clark Fork requires judgment and caution. The section from Clinton to Missoula grows progressively wider and deeper, making wading difficult except at riffle crossings and shallower stretches. Drift boat fishing is the dominant approach on the lower river; the upper reaches above Clinton offer excellent wade-fishing opportunities with more intimate dimensions.
The hatch calendar mirrors its major tributaries. Mother Day Caddis in May produces some of the most spectacular surface feeding of the season. The Clark Fork tends to be the last Missoula-area river to clear after spring runoff, typically fishing well from late June onward. Golden Stones and caddis dominate the summer, with terrestrials carrying the fishing through August. Fall Blue-winged Olive hatches on overcast days can be exceptional, with fish rising freely in the slower pools and flats.
Access from Clinton to Missoula is strong, with numerous public access sites, bridge crossings, and informal entry points. The abandoned railroad corridor paralleling portions of the river offers access to less-pressured water for anglers willing to hike — though land ownership along some stretches is complex, and trespass concerns exist. In Missoula itself, the river splits into two channels; floaters should use the left channel to avoid a dam and portage.
Missoula is the hub for Clark Fork fishing, with Grizzly Hackle Fly Shop and the Missoulian Angler Fly Shop providing expert guidance, gear, and guided trips. The Missoula Montana Airport makes the region easily accessible from virtually anywhere in the country. A Clark Fork float through the heart of Missoula is a uniquely Western experience — urban river fishing with mountain views and world-class trout.
