All buildings or structures hereinafter erected, reconstructed, altered, enlarged or moved, and uses of premises in the City of Gardiner shall be in conformity with the provisions of this Ordinance. All new principal and accessory structures, excluding functionally water-dependent uses, must meet the water body, tributary stream, or wetland setback requirements of § 7.7, Dimensional Requirements. No building, structure, land or water area shall be used for any purpose or in any manner except as permitted within the district in which such building, structure, land or water area is located.