The coloured bands on our lake maps are not decoration. Each one is a depth range, and the place where two bands meet is the edge — the drop-off that holds fish.
Why bands and not one number
"Max depth 9 ft" tells you almost nothing. A lake that is nine feet everywhere fishes completely differently from a lake that is three feet across the flats with a nine-foot channel through it. The first is a bathtub; the second has structure. Bands show which one you are looking at.
How to read the edges
Tight bands mean a steep drop: the bottom falls away fast, and that line is where baitfish stack and predators sit. Wide bands mean a slow taper — good for wading and working a flat, less useful for finding a hard edge.
The narrow neck between two wide areas is usually the best-known spot on any lake, and you can see it before you leave the house.
Where the numbers come from
Soundings — boats that ran the lake with an echo sounder. We take the survey, cut it into bands and close them against the shoreline. If the shoreline is missing, the contours hang in open space, so we do not publish them at all.
When there is nothing
Plenty of lakes have never been surveyed. Those pages say the depth is unknown. We would rather tell you that than draw a plausible blue shape no boat ever measured.
