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St. Vrain

**Please note: Flies & lures are the only types of angling techniques permitted within the Lyons Town limits; the Town of Lyons enforces a strict catch & release method only.

Fishing in Lyons

By The St. Vrain Anglers

The St. Vrain River was named for Cerran St. Vrain, who was an early French trapper involved in Bent’s Fort, the first permanent trading post established by white men in what is presently Colorado.

The St. Vrain finds its source in the mountains west of Lyons and begins as three small tributaries which ultimately join in town. The South and Middle St. Vrain begin in the Indian Peaks Wilderness area, while the North St. Vrain starts in Rocky Mountain National Park. In the upper reaches, each branch of the stream has cutthroat trout. As the river drops in elevation, there are fewer cutts, and more brook and brown trout. The browns remain in the river through Longmont, but are joined by a smattering of holdover rainbow trout in certain areas. The fish are mostly on the small size, due to the fluctuation in water levels. During winter months, much of the St. Vrain is frozen and is not fishable.

Since the stream begins at very high elevations – above 12,000 feet – the upper reaches are fishable for only a few months of the year. It is often difficult to access these areas before early July. As the stream drops in elevation, depending on snow pack and other weather related issues, the fishing areas are more accessible.

The St. Vrain is probably most popular for fly fishing during summer months, after runoff has completed its course. When the water begins to drop, the fish become more active, feeding on an abundance of aquatic insect life. The river has the most diverse caddis population of any stream on the Front Range of Colorado, so caddis patterns work well. Small, dark patterns and larger, lighter patterns catch fish throughout the season. While caddis predominate, there are also many mayfly and stonefly insects in the water as well. Patterns that imitate PMDs (Pale Morning Duns) include Red Quill, Ginger Quill, Lt. Cahill and so on. There are also Green Drakes on the St. Vrain. Stimulator patterns work well to fool fish that eat golden stoneflies. Nymphs in brown and olive from size 10 to 18 are useful, and should include pheasant tail, prince nymph and copper john. The Rundown

River: The St. Vrain River has three forks – the North, Middle and South. All begin in either Rocky Mountain National Park or Indian

Peaks Wilderness Area. The higher areas fish well, but you must hike to reach them. The North fork is eventually dammed at Ralph Price Reservoir. Below the dam, the river has some public access, and then joins Highway 36 near Lyons. Public access from there to town is available, although much of it is private. The Middle fork follows Hwy. 7 near Allenspark to Lyons, where it joins the North. The South fork is brushy and has less access. It joins the Middle near the South St. Vrain Canyon, also known as Hwy. 7. The St. Vrain flows through Longmont and joins the North Platte in the plains.

Water: Much of the St. Vrain system is brushy, shallow and has lots of pocket water. There are flatter areas occasionally. The river freezes for much of its reaches from November through early March. The low water during winter months is a problem.

Access: High country access is good as most of the water is on public land. Other areas should be studied on a map. The portion of the Middle through the South St. Vrain Canyon are mostly public, with many pullouts along the road. Bohn Park in Lyons, and along Hwy. 36 west of town are popular access areas. Beyond that there is not much public access east of Lyons.

Fish: The upper reaches of all three forks have populations of cutthroat, brook and brown trout. The lower you get in elevation, the more the browns take over, eventually joined by rainbows. The lowest stretches have browns, which exclusively inhabit the river in Longmont.

Bugs: The St. Vrain has many caddis flies, also mayflies, midges and stoneflies. It is not as well known as some streams for concentrated hatches, though the St. Vrain offers diverse fishing opportunities.

Flies: Flies to imitate the bugs; elk hair caddis; attractor patterns in pocket water; during summer months, moderate sized patterns – 12 to 16 – will work well.

Techniques: Lots of pocket water fishing. The upper stretches are small and brushy. Short, accurate casts are called for most times.

Seasons: Best during spring, summer, and fall.

Rating: The St. Vrain is a great small stream with good access for local residents. One can fish in the canyons for a few hours before, during or after work in the summer months. The fish are small, but wild and feisty and will eat dry flies with a good presentation.

Reprinted from LyonsFirst Guide Book originally published by the Lyons Area Chamber of Commerce