The department shall assist communities in preparing and obtaining data and other necessary information for the delineation of floodplains and floodways. When the department determines sufficient technical information is available for the delineation of floodplains and floodways on a watercourse or lake, the department shall consult with the appropriate district and each affected community. The department, the affected community, and the appropriate district shall consider flooding experiences, plans to avoid potential hazards, estimates of economic impacts of flooding on the community, both historical and prospective, and other data as the district and community may consider appropriate. Upon obtaining and developing the necessary information for delineation of the floodplain and floodway, the department and the affected community shall notify the appropriate federal agency and request that the information be used to delineate the floodplain and floodway under the national flood insurance program [42 U.S.C. § 4001 et seq.]. The regulatory floodway must be able to carry the waters of the base flood without cumulatively increasing the water surface elevation of the base flood more than one foot [30.48 centimeters] at any point.