All portions of the city extending from the mean high water line to the primary dune through or to the first manmade object, whichever comes first, on property now platted on Folly Island and controlled by the city or the state shall be retained and preserved by the city in trust as an area of conservation for the purpose of protecting the ecology of the property, the adjoining property, and of the beaches of Folly Island, for enhancing the environment, and for the health, safety and welfare of the residents of the state.
(`95 Code, § 5-10-1)