Possibly the most important part of fly fishing is learning how to read the water you are fishing! And one of my favorite parts about fly fishing for trout, has to be the fact that the conditions are constantly changing. If you grew up fishing stock tanks, ponds and lakes, like me, then reading water came easy. It was always still. You didn’t have to change how or where you fished, generally, ever. Temperature changes might move where the fish were, but the water stays the same. Just about the only change would be in clarity after you had a rain. Throw all of that out the window when it comes to fishing for trout in streams and rivers. In most mountain streams, there are rocks, pools, ledges, shoals, and many other natural (or unnatural) barriers to the flow of the water. All of these things cause fluctuations to the flow of that water. These fluctuations will be seen on the top of the water. Visually seeing the currents is pretty much the only way we can determine what the water is doing. Now, what is happening on the surface may not reflect what is happening on the river bottom, but we generally fish a stream based on what we can visualize. When you first walk up to a stream or river, you will instantly be told where and how to fish that body of water. This is where ‘reading’ the water comes in.
Trout spend all day, every day looking upstream for their food coming downstream. Keep this in mind, because PRESENTATION is the key to catching trout. By this, we mean that we need for our flies to float downstream just like all of the other insects the trout are feeding on, so knowing what the water is doing is the first part to achieving that perfect drift. (The second part is up to you…i.e. casting, line maintenance, fly choice and depth of flies. We’ll discuss in another post) So, when you walk up to the river, what do you see? Is the water flat and uniform or are there differing currents throughout. You may visually see boulders, trees, etc. in or out of the water affecting the flow or you may not see anything in the water, but the flows are differing across the water. When you see the water, do you instantly know how you are going to fish it? The beauty is that these currents will hold the clues to where the trout are! Think about it. Trout (generally) sit on the river bottom looking upstream for food coming downstream. These currents create feeding lanes for these trout. They do not want to exert unneeded energy to feed, so fish for them in the spots where they won’t have to work too hard for food. Let’s look at these spots.
‘Runs:’ Generally when we talk about runs on a river, we are referring to a ‘chute’ of water that creates a feeding lane. These can usually be easily seen because you have some sort of object (rocks, boulders, trees, islands, etc) creating that run and it is clearly visible. A run might be 6” wide or it might encompass the width of the stream. Based on the river topography, you might have multiple runs in a very small area. Spots where 2 or more runs converge, are a great spot for feeding fish to hold. Fishing runs: put those flies at the head of that run (where it starts) and dead drift them through it. Be careful of currents between you and the run. Those currents are most likely different from the speed of the water in the run, so make sure to mend accordingly or high stick that line off of the water. Depending on the size of the run, you will want to work the inside seam of the run (or seam closest to you), the middle and then the outside seam. Dries: just make sure your getting a good ‘dead drift.’ Nymphs: get that good dead drift, but also make sure you are getting down to the fish with heavy flies and/or split shot. Streamers: you can dead drift a streamer through it, swing it, or cast and strip the streamer through the run. You can try this from different angles and approaches.
‘Pools:’ Runs generally create faster currents and those currents create ‘pools.’ When you have run in a section of water, that water is generally faster than the water upstream of that run. The faster water, comes down and digs into the river bottom, creating a deeper area in that river. Those deeper sections are called pools. Again, depending on the water, a pool could be large or small. Trout like to hang out in these pools because the deeper water is cooler in the summer and the bottom is warmer in the winter. It also creates an easy feeding lane! Fishing pools: In pools the water generally slows down and creates a more manageable section to fish. Again, work those flies in the pool fishing spots closer to you, then gradually casting further across stream. We want to try to not put our line over the fish and spook them. In slower water, they will spook more easily. Fish those flies similarly to fishing runs, but watch our for ‘over mending’ (only mend when necessary) or making too much commotion on the water.
Tailouts: When you see a long, deep pool that shallows up before it goes back into forming another run, that is the tailout. The stream will generally get narrower and this will funnel the water. This creates another good spot for trout to feed. These are also generally the ares where you will see trout spawn, so watch out for redds in tailouts in the spring, when rainbows are spawning, and in the fall, when browns and brook trout spawn. Fish tailouts the same as above.
‘Pockets’ or ‘Pocket Water:’ Pockets are basically small pools. They are generally small areas of calm water in a turbulent stream where the trout will hold. When you look at a stream and you see chaos happening on the top of the water, but you also see areas of calm. These are your pockets. The varying opposing currents can create spots that are easier for feeding trout to sit and wait for food. You may have multiple pockets in a small area. You definitely want to fish these spots! Fishing pockets: These can be tricky to fish. They are generally small areas in a series of fast moving, opposing currents. Again, put those flies in that pocket and concentrate on getting a quick, dead drift. A lot of times you will be high sticking these spots because the water is so chaotic around them, but the good news is, you can generally get right over them and drop your flies into them. Fishing Pockets: If you see a series of pockets upstream, work one directly downstream of it by standing in the current (if safe) just below the pocket, only having just enough fly line out to cast. Cast your flies into the pocket, and immediately raise your rod hand, getting any of your line off of the water, and follow those flies with your rod tip. Trying not to move them at all…i.e. DEAD DRIFT! Twitching streamers through pockets can be $!
‘Eddies:’ Eddies are sections of the water that, because of a barrier to the current, flow back upstream. The easiest place to spot an eddy is behind a rock. You will see the water coming around both sides of a rock, but directly behind (or downstream) of the rock, the opposing currents on both sides are creating the water directly behind the rock to go back upstream towards the rock. You will also see eddies along banks where a fast current coming down, creates an eddy on the opposing bank. Eddies are great spots for trout to hang, but you have to make sure you are fishing it properly. Fishing eddies: It’s generally more effective to fish the small slow seam going downstream between the eddy and the faster currents. The fish can see your flies coming down at an appetizing pace and will hopefully, pounce on them! Streamer fishing eddies can be tricky because the current between you and the eddy are opposing. It is generally more effective, for me, to streamer fish eddies directly upstream or directly downstream of them. This doesn’t allow the current to pull your line and create a unnatural presentation.
Remember, trout sit in feeding lanes and spots where it is easiest for them to feed. Food (aquatic insects) get funneled downstream into these areas of the water. If it is fast moving water, the fish don’t want to exert excess energy to feed, so hit the slower edges, pockets and pools of that fast current. Also, the holding pattern of trout will change throughout the year. Cold water holds more dissolved oxygen than warm water. This means, during the colder months, more oxygen is in the water and trout can stay in the slower sections of the river. As the water temperature rises, trout will move to the more ‘turbulent' sections of the stream. The more turbulence a stream displays, such as rapids, waterfalls and breaks, the more oxygen is absorbed into the water. That’s why you will find trout in these stretches of water during the warmer months.
These are some of the most typical parts of a stream that the currents will create. If you look at enough parts of a stream, you will see all of these areas in a very short section. Understanding how the structure of a stream creates different currents, that then form these areas, will get you well on your way to understanding where trout will be in these parts of the water and why. If you spend a little time observing the water, you can instantly come up with a gameplay on how to fish it. After all, we go out fishing to catch fish. Get to know your streams and most importantly, how the water reacts to the topography of that stream, and you will be rewarded. Remember, trout fishing puts you in some extraordinary places. Take some time to enjoy the beauty of that place and make the most of it. If you have any questions, don’t hesitate to ask the friendly folks at MountainBound Fly Guides!