Pond Size

A reasonable estimate of the pond’s surface area is needed if the pond is to be managed for optimum fish production. Stocking rates, application rates of fertilizer and lime, and harvest rates of fish are all based on the pond’s size (surface acres).

The following formulas can be used to estimate size based on the shape of the pond: a rectangle or square: surface acres = length (ft.) x width (ft.) ÷ 43,560 (sq. ft. in an acre); if the pond is in the shape of a circle: determine diameter (distance across the middle of the pond in ft.) and divide by 2. Multiply that number by itself, multiply by 3.14, then divide by 43,560. A triangle: surface acres = ½ length of dam (ft.) x the length of the pond (ft.) ÷ 43,560.

Distances can be determined by a measuring tape, range finder, or by pacing. Some contractors or technical personnel may have GPS capability to calculate pond size. If the pond is to be stocked by the Wildlife and Freshwater Fisheries Division, fishery biologists will estimate the acreage upon inspection. Acreage of old ponds can be determined by aerial photos from the local NRCS office.

The information above came from the Alabama Wildlife and Freshwater Fisheries Division's booklet Sportfish Management in Alabama Ponds, which is available as a PDF.