Obstructions or increases may only be permitted if amendments are made to this chapter, the Official Floodplain Zoning Maps, floodway lines and water surface profiles, in accordance with § 305-33.
A. 
In AE Zones with a mapped floodway, no obstructions or increases shall be permitted unless the applicant receives a conditional letter of map revision from FEMA and amendments are made to this chapter, the Official Floodplain Zoning Maps, floodway lines and water surface profiles, in accordance with § 305-33. Any such alterations must be reviewed and approved by FEMA and the DNR.
B. 
In A Zones, increases equal to or greater than 1.0 foot may only be permitted if the applicant receives a conditional letter of map revision from FEMA and amendments are made to this chapter, the Official Floodplain Maps, floodway lines, and water surface profiles, in accordance with § 305-33.
The governing body shall change or supplement the floodplain zoning district boundaries and this chapter in the manner outlined in § 305-34. Actions which require an amendment to the ordinance and/or submittal of a letter of map change (LOMC) include, but are not limited to, the following:
A. 
Any fill or floodway encroachment that obstructs flow causing any increase in the regional flood height;
B. 
Any change to the floodplain boundaries and/or watercourse alterations on the FIRM;
C. 
Any changes to any other officially adopted floodplain maps listed in § 305-5B(2).
D. 
Any floodplain fill which raises the elevation of the filled area to a height at or above the flood protection elevation and is contiguous to land lying outside the floodplain;
E. 
Correction of discrepancies between the water surface profiles and floodplain maps;
F. 
Any upgrade to a floodplain zoning ordinance text required by § NR 116.05, Wis. Adm. Code, or otherwise required by law, or for changes by the municipality; and
G. 
All channel relocations and changes to the maps to alter floodway lines or to remove an area from the floodway or the floodfringe that is based on a base flood elevation from a FIRM requires prior approval by FEMA.
Ordinance amendments may be made upon petition of any party according to the provisions of § 62.23, Wis. Stats. The petitions shall include all data required by §§ 305-19D and 305-26B. The land use permit shall not be issued until a letter of map revision is issued by FEMA for the proposed changes.
A. 
The proposed amendment shall be referred to the zoning agency for a public hearing and recommendation to the governing body. The amendment and notice of public hearing shall be submitted to the Department regional office for review prior to the hearing. The amendment procedure shall comply with the provisions of § 62.23, Wis. Stats.
B. 
No amendments shall become effective until reviewed and approved by the Department.
C. 
All persons petitioning for a map amendment that obstructs flow causing any increase in the regional flood height shall obtain flooding easements or other appropriate legal arrangements from all adversely affected property owners and notify local units of government before the amendment can be approved by the governing body.