Peanut Island was originally created in 1918 as a result of material excavated when the Lake Worth Inlet was created. Originally called Inlet Island, Peanut Island amounted to only ten (10) acres. By 1923 the Port was using the island as a spoil site for the maintenance of the inlet and the Port shipping channel. The Port sold the northern half of the island in 1991 to the Florida Inland Navigation District as a spoil site for the Intracoastal Waterway maintenance dredging.
Today, as a result of continued maintenance dredging of the inlet and the Intracoastal Waterway, Peanut Island comprises approximately eighty (80) acres. The primary use of the island will continue as a spoil site but the Port Authority and FIND have generously made the perimeter of the island available to the public as a park through a long-term arrangement with Palm Beach County.
The name Peanut was given to the island when the State gave permission for use of the island as a terminal for shipping peanut oil. Plans for this enterprise were abandoned in 1946, but the name was retained.