Updated: Sep 17, 2022
Perhaps the easiest thing to learn about fly fishing is where to find the trout in a river. Reading the water is vital to locate fish, but also for you to maximize your casts and catch more of those fish. All you have to do is remember two things when approaching: one, trout are lazy, and two, they always face into the current. No matter what water you are fly fishing in the Shenandoah Valley or anywhere for trout in Virginia the same things apply.
The lazy aspect of trout is simple survival for any animal. They want to eat as much as possible and exert as little energy as possible. As they grow larger they compete for the best spots in the stream and once they've established that spot they eat more to fend of others that might want it. Just like pecking orders in flocks of birds, there is a pecking order in trout that share the same waters. So what we want to lock for is areas where trout can take it easy, be protected, not exert energy, and have food come to them. They aren't going to sit in the middle of heavy flow as there is likely just not enough food to pay off fighting all the current. They'll sit to the side of the current or on the bottom of the pool where the food will spill into. Side eddies, under trees or root balls, behind rocks the break the current, all these places offer some protection and a place where food would likely collect.
The second thing to remember is that trout always face into the current. That might not always be upstream. Eddies are little side whirlpools and a fish might face in any direction depending on the flow. These side pockets offer a great spot to land a fly, but create tricky line control situations so make sure you are in the right position to reduce drag. Trout can see everywhere but behind them so if the water is clear you need to take your presence into account.
Like you and I in the wintertime, these trout basically want to put sweatpants on and get fat and lazy. Put your fly in places that make it easy for the fish and you'll catch more. Reading the water is just that simple.