Field brief

The old river channel

The flooded bed of the river or creek the reservoir was built on, still winding along the bottom.

Why: It is the deepest, most continuous feature in the impoundment and the main travel route. Almost every good spot on a reservoir is where something else touches the channel.

Find it: Follow the shape of the valley above the waterline and read it downward — the channel usually runs where the ground falls away fastest.

Water level is the whole read

Reservoirs are managed. Level can move metres within a season for irrigation, power, flood control or drought.

Why: Level decides which structure is in the strike zone, which ramps are usable and what is submerged just under the surface.

Find it: Read the bathtub ring on the bank. Then check the current level and the operating agency's plan before you commit to a launch.

Creek arms and secondary points

The side arms feeding the main body, and the points that step down into them.

Why: Arms warm and colour up first, hold spawning and staging fish, and give shelter when the main body is unfishable.

Find it: Work from the mouth of an arm inward. The secondary point inside the arm is often better than the main-lake point outside it.

Standing timber and flooded structure

Drowned trees, fence lines, roadbeds, foundations and bridges left in place when the valley was filled.

Why: Vertical cover in open water: it holds fish at every depth and marks exactly where the old ground contour was.

Find it: Treat any line of timber as a former edge — a bank, a road or a field boundary. Fish the line, not individual trunks.

Riprap, the dam face and hard shorelines

Engineered rock along the dam, causeways and bridge approaches.

Why: Rock holds heat and crayfish, and the transitions — rock to clay, rock to timber — concentrate fish far more than the middle of a long rock bank.

Find it: Fish the ends and the changes. A hundred metres of uniform riprap fishes like ten metres repeated ten times.

Inflow and colour lines

After rain, the upper arms run coloured and a visible line forms where stained water meets clear.

Why: A colour line is an edge that fish use exactly like a weed edge or a drop-off, and it moves with the inflow.

Find it: Follow the line rather than staying on a spot. The line is the structure that day.