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7-minute read · Updated 2026-06-03

How to read a topo map for fishing: structure, contours, and high-percentage spots

The five contour patterns that hold fish on every reservoir in the US — and how to mark them before you ever launch.

Read contour density, not depth

Tight contours = steep drop. Loose contours = flat. Fish hold where contour density changes — the transition from steep to flat, the saddle between two humps, the inside turn of a creek channel.

Pattern 1: Secondary points

A point INSIDE a spawning pocket — not the main lake point. Pre-spawn bass stage on these in 6–12 ft. Look for a contour line that fingers out into a bay.

Pattern 2: Channel swings

Where the old river channel bends and touches a flat. Fish hold on the inside of the swing in summer, outside in winter. Walleye, crappie, and bass all use them.

Pattern 3: Humps and saddles

Offshore humps that top out 8–18 ft below the surface, surrounded by deeper water. The saddle between two humps is a highway. Drop a waypoint on the high spot AND the saddle.

Pattern 4: Long tapering points with brush

Main-lake points that taper a long way out before dropping. Add brush from the lake's brush-pile map (most TVA and Corps lakes publish one). This is your summer ledge program.

Pattern 5: Creek-channel intersections

Where two creek arms meet — current, depth change, and forage funneling. Mark every junction. Fish them in fall when shad pull into creeks.

Put this on the water

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