Mean wave power density estimates represent naturally available US wave energy, derived from measurements observed during a 51-month study period. Measurements were taken from 42,000 grid points out to a distance of 50 nautical miles from shore. Values represent the average instantaneous power generated by a meter length of wave crest per grid point. In accordance with accepted global practice, wave power density is measured in kilowatts per meter of wave crest aggregated across a unit diameter circle. Data were classified using quantiles. Bathymetric effects are known to have a large effect on wave characteristics at depths shallower than ~20m on the east coast and ~50m on the west coast. Reliable site-specific information in shallow waters can only be produced using results from models with higher spatial resolution that include shallow-water physics. Results may not be accurate in the shallower waters of the inner continental shelf.