Pre-Runoff Fly Fishing | What to Expect

Pre-Runoff Fly Fishing – What to Expect:

Spring has finally arrived in the Vail Valley and locals and tourists alike begin to focus on water in a more liquid form than the frozen, skiable type. Here at Vail Valley Anglers our wade guides have been busy with half-day trips focused around the midday or warm afternoon hours. And the float guides have pulled boats out from under the security of tarps and winter equipment all to take advantage of the excellent pre-runoff fishing conditions.

The Water:

During the springtime our local rivers experience a daily fluctuation in water levels. Valley snowmelt begins with the warmth of the spring days swelling the rivers, increasing the flow and then settling down, lowering the flow with the cool nighttime temperatures. This warm and cold temperature pattern causes these small peaks and valleys in the river runoff. Turbidity can also be an issue with localized streams pushing muddy runoff into the river. Vail Valley Anglers can give you up-to-date river conditions with the ease of a phone call, 970-926-0900.

The increase in flow causes a disruption along the river bottom dislodging worms, stonefly nymphs and more. All kinds of food sources tumble along the bottom in the river current delivering a smorgasbord of food items to hungry winter-starved trout. Rainbows, in preparation for their spawn, eat to bulk up before the heavy toll of spawning exerts its primal grip.

The Fish:

The trout are putting on the feedbag. They are eating the daily emergence of midges and the first hatches of Blue Wing Olives along with the multitude of other food items being washed downstream caught up in the spate. Browns are actively chasing streamers stripped along the river bottom and in pockets along the shoreline. Rainbows are dressing up in spawning colors and clearing off redds. As water temperatures begin to increase there is an equal increase in trout metabolism and activity.

What to Throw?

As pre-runoff progresses, focus begins to fall upon a variety of small nymphs and a few stonefly nymphs. Midge larva and pupae will take trout during the day before the daily Blue Wing Olive hatch begins. Small Pheasant Tails mimic the Baetis hatch found on our local rivers by imitating the prevalent Blue Wing Olive mayfly nymph.

Small baitfish, sculpins and immature trout are washed downstream in the tumultuous currents. At the mercy of the overwhelming flow they become easy targets for strong swimming predators. Heavy streamers raked across the river bottom solicit powerful strikes from predatory brown trout. Large profile flies like Pat’s Rubber Legs or the Umpqua Twenty Incher nymph imitate the insects inadvertently knocked loose by the moving water.

Line and Tippet:

Now is a time to pull out the 4x tippet—maybe even 3x—depending on the conditions that day. Save your Fluorocarbon and fine monofilament for the educated trout in tailwaters, or for the fine eyes of Trico sippers later in the Summer. Vail Valley Anglers carries a huge stock of tippet from manufacturers such as RIO and Umpqua. Beef up your leader for streamer fishing as well.

Our shop has a large selection of leaders from RIOUmpqua and Airflo. Strong leaders and heavy tippet provide a lot of advantages when it comes to fighting fish. The ability to land fish quickly is a bonus when it comes to catch and release fishing. Think Fish First!


The massive spawning activity that occurs by rainbow trout creates the telltale signs of cleared gravel and indicates a prevalence of eggs in the watershed. Brown trout will recognize the overabundance of the high-protein food source and begin to stage directly downstream from any spawning activity. Take care to not wade directly into spawning grounds and to target downstream of active beds to attract non-spawning brown trout.

How to be safe:

The powerful river currents will overturn rocks and tumble gravel bars dislodging logs and debris. The currents disrupt the river bottom and wading anglers also need to be attentive to river conditions. Pre-runoff can be a treacherous time to fish on foot. Exercise extra caution when wading in pre-runoff conditions. Just like fish eating insects dislodged from moving rocks, logs, and crumbling banks, wading anglers encounter loose shorelines, unstable rocks, and floating logs (both above and below the water line.) In these precarious wading conditions, the best advice is to purchase a wading staff. And use it. At Vail Valley Anglers, we carry collapsible staffs by Fishpond and Simms to attach to your wading belt.


Now is the time to prepare your boat for the really high water soon to come. Replacing worn out components and double-checking rafts for slow pinhole leaks is better accomplished now. Picking up one of the new “heavy-duty” coolers for your raft or drift boat like a Yeti or Orion type is an excellent addition to your river gear. Vail Valley Anglers has a model sure to fit your needs.

Final Thoughts:

Whether wading or floating springtime pre-runoff can offer some excellent opportunities for the fly fishing angler. Knowing the river conditions and the watershed ensures successful outings before the real high water fills our riverbanks. Targeting post-winter, aggressive Brown trout produces some of the best catches of the year. Call Vail Valley Anglers to book a pre-runoff fly fishing trip on foot or by boat today.

Mike Salomone | Fly Fishing Guide & Content Writer