Fishing a freestone through runoff and after it

A freestone river is fed by snowmelt, rain and tributaries rather than by a dam. In Colorado that means the Poudre, the Arkansas, the Eagle, the Roaring Fork and plenty more, and it means that for several weeks each spring those rivers do something that no amount of good gear will fix.

Runoff is not a hard season to fish. It is partly a season not to fish, and knowing the difference is the most valuable thing in this guide. What follows is what changes when you do go, and where the line is.

What runoff actually does to a river

• Volume rises, often dramatically. A river can run at several times its summer flow.
• Clarity collapses. Meltwater carries sediment, and visibility can drop to inches.
• Water gets very cold. It is snow, very recently. Fish metabolism drops with it.
• Fish move out of the main flow. Holding in the middle of a river at four times normal volume is not worth the calories, so they go to the edges, behind structure, and into slower water.
• Wading gets dangerous. This is the part that matters most, and it is not a gear problem you can buy your way out of.

The single most important adjustment is where you look. In runoff the fish are usually within a few feet of the bank, in water you would walk straight past in July. People drive to a swollen river, stare at the raging middle, conclude it is unfishable, and never look at the two feet of soft water by their boots.

Safety first, and this is not a formality

High cold water kills people every year, and it does it to competent waders. Moving water exerts far more force than it appears to, that force rises sharply with depth and speed, and cold water removes your ability to do anything about it within minutes.

What genuinely helps:

• A wading staff. Not optional equipment at high flows. A third point of contact changes what you can stand up in, and it lets you probe depth ahead of committing your weight.
• A snug wading belt, worn tight. Waders do not drag you down like an anchor, but they will fill and make swimming very difficult. A tight belt limits how much gets in.
• Boots with genuine grip, and studs where allowed. Felt and rubber behave differently on different substrates, and studs add real bite on slick rock. Check local rules: felt soles are restricted in some states as a biosecurity measure.
• A personal flotation device on big water. Unfashionable, and the correct choice on rivers like the Arkansas or the Colorado at high flow.
• Fishing with someone. The cheapest safety equipment there is.

And the honest rule that no gear replaces: if you are not confident you can stand up in it, fish from the bank. There is no fish in any Colorado river worth the alternative, and the bank is where they are in runoff anyway.

Rod and line: heavier than your usual

Everything about high water pushes towards more capability. You are casting heavier rigs, often with more weight, frequently into wind, and you need to move a lot of line to control a drift in pushy current. You may also need to hold a decent fish out of a current that is trying to take it downstream.

This is the situation that justifies a heavier line weight than you would normally fish for trout. Length helps too, for the same reason as always: reach is line control, and line control is everything when the current is doing this much.

Weight, and then more weight

To get a fly in front of a fish holding near the bed in fast high water, you need it down quickly, because the window is short and the current is trying to keep your fly up and moving.

Practically: heavier flies than you would normally fish, additional weight on the leader, shorter and more controlled drifts, and the acceptance that you will lose some rigs to the bottom. Losing flies in runoff is a sign you are fishing at the right depth. Not losing any is a sign you are fishing above the fish.

Carry more of everything expendable than you think you need. The rate at which a high river takes flies, tippet and weight is considerably higher than in summer.

Tippet: stronger, and that is fine

This is the reverse of the tailwater situation. Visibility is poor, so fish are not inspecting your tippet, and you have to move heavy rigs and hold fish in fast water.

Go heavier than usual, without much hesitation. Off-colour water is the one time you can fish tippet strong enough to actually land what you hook and to pull a snagged rig free rather than break it off. The refinement that matters in clear water is wasted here.

Visibility: the one thing you can genuinely design for

In water with inches of visibility, a fish has to be able to find your fly. That points at larger profiles, more contrast, and flies that push water or flash rather than imitate delicately.

The same logic applies to your indicator: you need to be able to see it in broken, fast, glaring water, which is the one situation where a large bright one is the right answer rather than the lazy one.

Polarised glasses stop being about spotting fish, which you will not be doing, and become about reading the surface for structure and about not getting hit by a heavy fly on a windy day.

Staying dry, because you will get wetter

Spring in Colorado alternates between warm sun and cold squalls, sometimes within an hour, and you are standing next to a large volume of very cold water.

• A genuinely waterproof rain shell, not a water-resistant one, cut short enough not to bunch over waders.
• Layers you can shed and add, since the temperature range within a single day is wide.
• A dry change in the car. Not fishing kit, just dry clothes. After the day you have a wet, cold drive, and after an unplanned swim this stops being a comfort item.

When it is worth going at all

The most useful skill here is triage, done before you drive. Read how to read a river gauge for the mechanics, but the short version for runoff:

• Rising fast and well above the seasonal median: probably not worth it. Fish somewhere else.
• Peaked and falling steadily: often very good, and improving daily as clarity returns.
• Stable, even if high: fishable, with the adjustments above.
• Rising after a warm night: expect the afternoon to be worse than the morning, since a warm night means more melt arriving during the day.

The other answer: fish a tailwater instead

When the freestones are unfishable, the tailwaters generally are not. That is the whole reason they matter in Colorado. A reservoir catches the sediment and meters out the flow, so the Fryingpan, the Taylor, the Blue and the South Platte tailwaters stay clear and stable while their freestone neighbours blow out.

That is a completely different gear problem, and it is covered in what a Colorado tailwater day asks of your gear. Knowing which of the two you are driving to is the actual decision, and our river guides label each water so you can make it.

Before you go, check the gauge for your specific reach on USGS current water data, and check current regulations, access and closures with Colorado Parks and Wildlife. Nothing on this page is a safety assessment of any river or of conditions on any particular day.