RIVER REPORT
North St. Vrain | Button Rock
The North St. Vrain River below Button Rock Reservoir is a picturesque tailwater fishery offering exceptional fly fishing opportunities in Colorado’s Front Range. Fed by cold, steady flows from the reservoir, this section of the river supports a healthy population of rainbow, brown, and cutthroat trout, thriving in the clear waters and abundant aquatic life. Anglers will find a mix of deep pools, riffles, and pocket water, making it an ideal spot for both nymphing and dry fly fishing. Surrounded by lush forests and steep canyon walls, the river provides a tranquil escape with stunning scenery. With its rich insect life and pristine water conditions, the North St. Vrain below Button Rock is a hidden gem for fly anglers seeking a peaceful and productive day on the water.
CONDITIONS
Weather & Flow Data Reported From OpenWeather and USGS
Recent Reports
North St. Vrain Creek Below Button Rock Reservoir – April Fly Fishing Report: As of early April, the North St. Vrain Creek below Button Rock Reservoir is experiencing typical spring conditions with low and clear flows. Anglers can anticipate hatches of midges and Blue-Winged Olives (BWOs) during warmer midday periods, providing opportunities for both nymphing and dry fly fishing. Effective nymph patterns include Pheasant Tails, Copper Johns, and RS2s in sizes 16–20. For dry fly enthusiasts, BWOs and midge patterns in sizes 18–22 can be productive during active hatches. Additionally, small streamers such as Woolly Buggers and Sculpzillas can yield positive results, especially during overcast conditions. Employing light tippets (5x to 6x) and a stealthy approach is advisable due to the creek’s clear water and wary trout. Focusing efforts during the warmest parts of the day, typically late morning to early afternoon, can enhance success rates. Overall, the North St. Vrain Creek below Button Rock Reservoir offers rewarding opportunities for anglers this April.
Water Flow Data
5 Day Outlook
BUGS
North St. Vrain River’s insect life provides a smorgasbord for hungry trout. AvidMax recommends these key fly patterns:
THE FISHERY
The North St. Vrain River below Button Rock offers anglers a pristine tailwater fishing experience, with clear, cold flows and abundant trout in a secluded canyon setting that’s perfect for a peaceful day on the water.
Fish Species
North St. Vrain Creek below Button Rock Reservoir is home to populations of wild brown and rainbow trout, with browns being the predominant species. Trout typically range from 10-16 inches, though larger fish can be caught, especially during the fall when brown trout become more active in their pre-spawn phase.
Unique Fishing Conditions
This section of North St. Vrain is a tailwater fishery, meaning it benefits from cold, consistent flows from the Button Rock Reservoir, making it productive year-round. The creek features a mix of riffles, deep pools, and pocket water, offering great opportunities for nymphing and dry fly fishing. Summer and fall bring excellent dry fly action with caddis, blue-winged olives, and terrestrials like ants and beetles. Nymphing with midge, mayfly, and stonefly patterns (sizes 16-20) is effective year-round, particularly in deeper runs and seams.
Access and Regulations
Public access to the North St. Vrain below Button Rock is available through the Button Rock Preserve, which is accessible by a short hike from the parking area near Lyons. The area is catch-and-release only, and artificial flies and lures are required to maintain the health of the wild trout population. Anglers should be prepared for a hike to access the river and should check water flows before heading out, as releases from the reservoir can affect fishing conditions.
TACTICS
AvidMax encourages anglers to explore their full repertoire on the North St. Vrain River:
Nymphing
Nymphing allows anglers to target trout feeding below the surface, with or without an indicator, making it an effective technique for covering deep runs and slow pools where fish are actively feeding on subsurface insects.
Dry Fly Fishing
Fishing with dry flies provides the ultimate surface experience, imitating adult insects and offering exciting visual strikes, particularly during hatches when trout are feeding on the water’s surface.
Streamer Fishing
Using streamers mimics baitfish and other larger prey, offering an aggressive approach that can entice bigger, predatory trout, especially when fishing deeper water or fast-moving currents.
SEASONS
Each season on the North St. Vrain brings unique joys and challenges for AvidMax anglers:
Spring
Spring runoff increases water levels, but nymphing with stoneflies and larger attractor patterns is productive in slower pockets and near the banks. Focus on calmer water where trout seek refuge from fast currents.
Summer
Summer brings great dry fly action with hatches of caddis, PMDs, and terrestrials like ants and beetles. Early mornings and late evenings are the best times to fish dries in riffles and runs.
Fall
Fall is an excellent time for streamer fishing, particularly for targeting aggressive brown trout during their pre-spawn period. Nymphing with small mayfly and midge patterns also works well in deeper pools as temperatures cool.
Winter
Winter fishing is slower, but trout can still be caught using small midge and baetis nymphs in deeper, slow-moving pools. Target midday when the sun warms the water, and trout are more likely to feed.
REMEMBER
The North St. Vrain River below Button Rock offers anglers a serene fishing experience, with its clear waters flowing through a rugged canyon setting. However, its fragile ecosystem and fluctuating water levels require anglers to fish responsibly to protect the health of this special fishery.
Water Conditions
Flows below Button Rock Dam can vary due to reservoir releases, especially in spring and early summer. Always check water levels before heading out, as sudden increases can affect fishing conditions and wading safety.
Regulations
The area below Button Rock may be subject to catch-and-release regulations, with artificial flies and lures only. Ensure you’re familiar with these rules to help protect trout populations and comply with local regulations.
Safety
The riverbed can be rocky and slippery, with faster currents in some sections. Wear proper wading gear, be cautious when navigating deeper pools, and always watch for sudden changes in flow due to dam releases.
COMMENTS
We want to hear from you! Have you fished this River or have any advice for fellow anglers?
Leave a Reply