Understanding current will be a vital to learning how to read water and determine where fish hang out. Fish are always in motion. Their survival depends on a positive balance between energy expenditure (-) and energy conservation (+). With this in mind, it makes sense that trout are usually found where:

1. Food is abundant

Healthy rivers and streams offer a variety of food sources (Midges, Mayflies, Caddisflies, Stoneflies, Terrestrials, Leeches, Crayfish, etc.). throughout the entire year. If the water you are fishing doesn't have much food, it probably doesn't have many fish.

2. Minimal effort is required

A trout's overall goal is to find a spot in the river where food is brought directly towards them, while exerting as little energy as possible to stay in place. This is where current comes into play...


Current varies from bank to bank and surface to riverbed.

Bank to Bank

Rocks, other debris, and bend in the river create an area known as a seam. This is where fast current and slow water meet (see picture below). Trout will hang out in the slower water near the edge waiting for food in the current. When a substantial meal passes by, they will zoom over, snag the food, then return to the slower water.


Surface to Riverbed

When analyzing the water rate at the surface, you may find yourself thinking, "It's way too swift for any fish to be right there." However, if you think about water movement from top to bottom, things change. As you go deeper, the water slows (see first picture below). This is because the water molecules are hitting up against the bottom and other debris (such as rocks, see second picture below) causing friction. This can slow the water enough to provide the perfect spot for trout to feed without exerting too much energy.


Understanding current will be foundational in the upcoming sections on different water types and tactics. The first water type we will cover is pocket water.