The term ‘reading the water’ probably seems like an odd phrase. If you’re an avid sailor you know exactly what I’m talking about. If you’re a meteorologist you know what I’m talking about. In a nutshell, reading water to a fly angler means you’re looking at the environment for clues to give you insight on where the fish may be. This is not unlike the way a sailor diagnoses the wind, or a weather person looks at the clouds to know what weather’s coming in the next few hours.
When I teach my fly fishing schools, I usually take my students to the river and then on a bridge. I then go upstream with a box of cereal. I usually get KIX or corn pops. They work great! I dump them into the river about 100 to 200 feet above the students. By the time the cereal gets down to the students the debris has gone from complete chaos to somewhat controlled paths. Veins of cereal are delivered to the students. These channels or veins are lanes of food for the trout. No, of course they’re not eating KIX, but they’re certainly eating bugs like ants, grasshoppers, and mayflies that are floating down the river, just like the cereal.
The lines of food are referred to as feeding lanes, and trout situate themselves in or near the feeding lanes so they can snatch food with a minimal amount of energy. This is what reading the water’s all about. The key to understanding how to find fish is also understanding that fish place themselves where they’re sheltered from the current and birds of prey, yet also are close enough to these feeding lanes to snatch up food; behind rocks, under foam lines, places like that.
The common equation fly anglers think about when they analytically look at trout is a trophy fish will never expend more energy to consume something that will give them energy. In other words, I won’t run two miles for a rice cake. But I will run two miles for a steak dinner.
So the next time you look at a stream, look for the foam lines. Imagine dumping a box of cereal in the water and guessing where the food will end up. Look for places where a fish could hide yet still quickly swim into the current to get a floating ant, and voila! You’re reading the water my friend!