42 U.S.C. § 4028

(a) No new flood insurance coverage may be provided under this chapter on or after October 1, 1983 , for any new construction or substantial improvements of structures located on any coastal barrier within the John H. Chafee Coastal Barrier Resources System established by section 3503 of title 16 . A federally insured financial institution may make loans secured by structures which are not eligible for flood insurance by reason of this section. (b) No new flood insurance coverage may be provided under this chapter after the expiration of the 1-year period beginning on November 16, 1990 , for any new construction or substantial improvements of structures located in any area identified and depicted on the maps referred to in section 3503(a) of title 16 as an area that is (1) not within the John H. Chafee Coastal Barrier Resources System and (2) is in an otherwise protected area. Notwithstanding the preceding sentence, new flood insurance coverage may be provided for structures in such protected areas that are used in a manner consistent with the purpose for which the area is protected.