6 Ways To Read River Water And Catch Fish

Chris Parsons Be The Blog, Fishing Tags: ,
reading trout water

Like a kid in a candy store is the angler appraising the possibilities of the river, fly rod in hand, waders and boots already baptized from the first moments of glorious emersion. The first cast is a connection to the waters flowing through the rocks, gravel, tree trunks and surrounding woodland. The orange of a setting sun or the warmth of a rising sun penetrates the ether. That first cast is an act of reverence derived from sublime wonder. The river’s waters are a mystery concealing the culmination of fly fishing truth. The truth in knowing instead of hoping. The river offers words that can be read not from a book but from within the waters. Reading those words is the process of reading the water. To read the water for an angler is to decipher the holding water of the rainbow trout, brown trout or maybe steelhead. Precise pockets, pools, riffles and runs are all components of a trout stream where fish that chase a tied fly pattern can be found.  Sort of like a programmer scans code, the angler scans the components of the river object model, identifying the variety of edges, watery variables.

Reading The Water

All fish found in a river reside on the edge of something. Reading those edges takes time spent fishing! Good old fashioned experience casting a fly rod perusing the waters of your favorite trout stream. There are six key components found on the rivers here in Northern California that always hold rainbow trout, brown trout and steelhead. Within these components are the edges that fish reside in. These types of edges can be found on any river that can be fished with a fly rod. All the components described below have these key features: Well oxygenated water, structure, cover and access to food.

river components
Amongst the components are the edges where fish are found.

1. Current Seams

Current seams are those creases that appear where faster and slower currents meet. A current seam is an edge. Typically a seam is a lateral feature where river nutrients are suspended long enough in small swirls for a fish to eat conveniently. Seams can provide slower, slim and stable currents trout favor. Seams are produced by the resistance of subsurface structure like rocks, trees, boulders and various transitions on the river bottom. Look for seams where the river widens into a deep channel along a bank. The bank of the river is an obvious edge. A seam is definitely an edge within a river created by other edges. Remember, edges are where fish are found. One of the key features on the Lower Sacramento that constantly produces big rainbows is current seams found along the edges of the giant riffles found between Redding and Red Bluff.

2. Tail-Outs

At the end of a riffle, past the pool or body of the entire *run is a section we call the “tail-out”. The tail-out is typically a shallowing section where river current gets compressed, widens or slows down due to a build up of river substrate deposits. But sometimes a run tails-out into deep water before being squeezed over a *lip and spilling into another riffle-run-pool and tail-out configuration. The tail-out of a run offers a siloing effect conveying food, oxygen to holding fish. Look in the tail-outs of riffles and runs on the Trinity River for steelhead or on the McCloud for rainbows trout and brown trout that will chase dry flies.
* a “run” is comprised of a riffle-run-pool and tail-out. In that order as the water flows.
* a” lip” is the very top of a run where water enters the beginning of a riffle.

slow water
Can you find the edges? Shade and transition.

3. Transitions

Transitions are an invisible edge to the uninitiated angler on a given river. If one doesn’t know the river intimately, it’s impossible to visualize the bottom contours of the river when the surface is smooth. Other than the assumption of rocks and boulders strewn about the river bottom, the contour of the river bottom is disguised. Transitions are edges that go from deep to shallow or vice versa. Transitions along the bottom of a river become the secret spots only the locals know about. The most likely place along a river to find those secret transitions is along flat featureless portions of the river. Think of those quiet, stagnant frog water sections you will be most likely to walk past or float through if drifting in a boat. Search the slow water. Look at color variations along the river bottom. Where you see sandy or lightly colored sections becoming dark and rocky, or a slight speed up or slow down of river current, these features indicate edges where fish will reside. Fish will hold in these not so obvious pockets or buckets along the bottom of the river, sitting just below conveyor belt speed water where they can easily intercept insects, caddis, mayflies, stoneflies while laying beyond the reach of sunlight and Osprey.

4. Glides

Water that has a laminar or even flow from top to bottom can be referred to as a “glide”. Usually a glide is the average depth of the entire length of a run. The glide is situated between the riffle or transition from shallow to deep but before the tail-out. So a glide can be anywhere from 1 ft to 10 ft or more in depth. Glides are excellent conveyors of food and oxygen offering shelter from sun and predators. Almost every glide on the McCloud River is fished daily during trout season with nymphs suspended under indicators. The fish are smart! Sometimes the fish found in a glide are really fickle and won’t come to a drifted fly. I like to fish dry flies in the slowest glides knowing that even though there isn’t a hatch happening or fish eating off the surface I am confident the fish will respond to a surface presentation of a beetle, ant, hopper or cripple pattern. Almost like a cat chases a string, trout will show up if you put that dry fly or nymph in front of them enough. High stick or short line technique is a favored approach I use when wading a glide.

Angler fishing a glide
Angler fishing a “Glide” below riffle of pocket water.

5. Pockets

Pocket water sums up many famous trout streams. The Pit River is comprised of riffles, runs, pools, glides and tail-outs but it’s the bubbly oxygenated pockets where rainbows love to hide on the Pit in addition to many other freestone streams. A pocket in a river is surrounded with the edges of rocks, boulders. Sometimes, pockets are like steps in the river where the waters flow down into a pool. A pocket of water to be exact is a short blink-of-an-eye bucket of water that requires a lot, and I mean a lot of split shot to fish nymphs through. Pocket water is known for harboring opportunistic trout that leap at the chance of munching on a dry fly like a hopper, golden stone or cripple caddis pattern. Nymphs fished high-stick style, without an indicator, are the key to finding fishy success fighting at the business end of your fly rod!

6. Pools

Pools are the easiest edge to identify on a river. They are those enticing, calm and clear expanses of water that just smack of trout, but seem to hardly hold anything that will chase a fly. None the less, there’s fish in the pools of river. A pool of water has it’s edges defined by where the current enters the pool and where current exits the pool. In the depth can be imperceptible currents that create seams that only the fish can detect and hold in. On a steelhead stream, a pool is an excellent holding or resting spot for a weary warrior from the sea. The depth of a pool can be an excellent location for steelhead to hide from the sun or drift boats.

Within each of the 6 river components described, and angler can find edges defined by the width of the river, depth, transitions from deep to shallow and vice versa. Big boulders, downed tress, the edge of shade or where a tributary enters the mainstem of the river. Temperature changes can be considered edges. If you can define an edge on any stream you can fish, chances are fish can be found along that edge. And if you confined fish, you’ll find fish food! That’s right! Stoneflies, caddis larva, nymphs of every aquatic insect order thrive along the edges that comprise a river.

So, your mantra when fishing the rivers of Northern California or anywhere in the U.S. is “edges”. Find edges and you’ll find fish.

Here’s a cool site I found that has a couple good images that depict edges and river components : Fly Anglers Online


Comment on “6 Ways To Read River Water And Catch Fish

  1. Great article! I really like the idea of fishing “edges”. My ability to catch fish really increased when I took a minute to try and read the water. Understanding where the fish will be, what they are eating, and how to catch them is much more efficient when you take just a few minutes to read the water before tossing out your fly.

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