Waterline

Waterlines are horizontal slices through a boat, parallel to the water surface. The design waterline (DWL) is the height on the sides of the boat that the water will come to with a desiginated load. Lofting waterlines are usually parallel to the design waterline and spaced 1 or 2 inches apart, both above and below the design waterline. Measurements from the table of offsets along waterlines describe the shape of the sides of a boat best.

Because the performance of a kayak depends on what is in the water, factors such as waterline width and waterline length are more important than length over all and maximum beam.