River: St. Vrain River; has three forks – the North, Middle and South; all begin in either RMNP or Indian Peaks Wilderness Area; higher areas fish well, but you must hike to reach them; North is eventually dammed at Ralph Price Reservoir; below dam, river has some public access; then joins SR 36 near Lyons; public access from there to town is available; much is private; Middle follows SR 7 from near Allenspark to Lyons, where it joins the North; the South is brushy and has less access; it joins the Middle in the SR 7 canyon. St Vrain flows through Longmont and joins N 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; river freezes for much of its reaches from November through early March; 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 SR 7 canyon are mostly public, with many pullouts along the road; there is some access in Lyons; not much public access east of there; some in parks through Longmont.

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 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; not as well known as some streams for concentrated hatches, 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 – 12-16 – will work well.

            Techniques: lots of pocket water fishing; upper stretches are small and brushy; short, accurate casts are called for most times.

            Seasons: best during Spring, summer, fall

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

About the St. Vrain: The St. Vrain is our namesake. This is the stream that runs through Longmont, which is where our first shop was located. The stream 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 Longmont, Colorado. It begins as three small tributaries which ultimately join in the town of Lyons. The South and Middle St. Vrain begins in 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, we find fewer cutt's, and begin to see Brook and Brown trout. The brown's remain in the river through Longmont, but are joined by a smattering of hold over 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 no 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. Parts of the stream between Longmont and Lyons are open year around.

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 PMD's (Pale Morning Duns) include Red Quill, Ginger Quill, Lt. Cahill and so on. There are also Green Drakes on the Vrain. Stimulator patterns work well to fool fish that eat golden stoneflies. Nymphs in brown and olive from size 10-18 are useful, and should include pheasant tail, prince nymph and copper john. 

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