Spring Runoff and Blown out Rivers

The days are growing longer here in the Colorado Rockies and the snow pack is starting to melt off. Thanks to some late spring snowstorms, the mountains are full of snow, a great sign for healthy rivers this summer.  It’s during this time of the year that rivers are soon going to be “blown out,” a term many anglers use to describe a river full of muddy sediment from the melting snow in the mountains.  It’s widely held that a river that’s blown out is an unfishable mess, but nothing could be further from the truth. 

Colorado Spring Runoff

Spring runoff means warming weather and warming weather means warming water.  In addition to fish becoming more active in their feeding hours and habits, plenty of insects are starting their life cycles at this time.  In fact, it’s the rising temperature of the water which initiates the hatch, and you can bet that hungry trout are going to be keying in on them, no matter the quality of water – trout are always looking for a meal.

The fact that the river may be over its banks and muddy is not something that will ruin a trip.  In fact, this type of environment can push large trout closer to the bank and make them accessible to a well-placed cast.  Trout are specially adapted to detecting vibrations in the water in order to find flies in low visibility water, but using a larger streamer or nymph is recommended.  And since it’s not widely apparent that this type of water is extremely fishable, you might be the only one on the river and the trout less pressured. Don’t let cloudy water scare you from what could be an amazing day on the river and a chance at some exceptional trout.

The only trouble you could run into is if the snow melt lowers the water temperature to the point that the trout start trying to conserve energy, as they are prone to do in the winter.  The best way to combat this is to try to get the nymph to the bottom as quickly as possible. The trout won’t chase flies as much and to get a strike you will need to present in a way that requires the least amount of effort on the trout’s part. Lead shot, sinking lines or weighted nymphs will help get the presentation just right in the deeper holes.

The Mighty Salmonfly

One of the most well-known and universally revered insects for fly fisherman is the salmonfly. They are one of the many insects that begin their life cycle in the spring. The salmonfly is an enormous, protein-packed insect that can sustain the appetite of the largest trout. Once trout reach a certain size, they typically stop feeding on the surface, as the rewards are not worth the effort. Not true with insects like the salmonfly-- they are too tempting for fish of any size. This is the one time of the year you can catch exceptionally large trout off the surface.

Fishermen travel across the country to fish famous salmonfly hatches in Colorado. And fortunately, we have some of the best in our backyard. Sometime in the next few months, large nymphs hatch in places like the Colorado River, make their way to the bank, molt, breed and lay their eggs. During this flurry of activity, the trout go hog wild, gorging themselves on the flies. This takes place in a short span of time, so timing is crucial – once the water temperature reaches 54-56 degrees, the hatch is imminent.  The time to plan is now. Pack your gear and give us a call for the latest information on this annual event.

If you spot feeding on the surface, it’s time to tie on a dropper rig with a stimulator and then the nymph below (size 2-10 Pat’s Rubber Legs, Big Ugly Stonefly, Girdlebug etc.). It’s a great way to fish; if you haven’t tried dropper rigs, you should give it a shot. The stimulator acts as an indicator for anything taking the nymph while also fishing for any surface action effectively. Here is a great link to how you should properly rig up a dropper.

There are several different ways to rig a dropper, including creating a “tag” off a blood knot or tying the tippet directly onto the bend of the hook. There are differing thoughts on which one is best, so testing every technique and learning what works for you is the best way to get your optimal dropper rig. I would also recommend that you use a higher weight of leader and tippet for these fish as they are larger, the current stronger and the need for a delicate presentation less important.

Unfortunately, with a bounty of food come more selective trout. Not only is there more food to choose from, but also the fish will be crammed full of food. In this situation, local insight is invaluable.  Having the wrong color or size of fly can mean the difference between a day full of fish or full of disappointment.  The best way to fish this kind of water is in a drift boat. Contact Cutthroat Anglers for prices and availability for a guided float trip down to give yourself a shot at the best trout Colorado has to offer.

The legendary salmonfly hatches of the American west are something to be experienced, not just read about.  These types of annual events are the sign of healthy rivers and healthy fish and what fisherman and conservationists strive to protect and preserve for future generations. Come out and join us in experiencing springtime in the Rockies. Break out the gear and make your way to Cutthroat Anglers for the full experience.  Our friendly experts are keen to share the latest information and provide expert advice. We are conveniently located in Silverthorne right on Highway 9.  Check your gear or pick up what you need before heading out. We hope to see you, and as always – tight lines!

Salmon Flies on the Colorado - Tips & Techniques from Colorado Parks & Wildlife on Vimeo.

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