A seawall comprising a base with a top, a plurality of extensions on the top of the base, and an adhesive or sealant securing the extensions to the base. Each extension comprises a plurality of spaced apart rubber poles extending generally in a direction horizontal to the sea floor, and an outer rubber covering surrounding the poles. A method of increasing the height of a seawall comprising the steps of placing a plurality of the extensions on top of the seawall with the poles extending substantially parallel to the sea floor, and securing the extensions to the top of the seawall.