Village of Darien, WI Chapter 18.20 Other Floodplain District

[HISTORY: Adopted by the Board of Trustees of the Village of Darien 2-21-2022 by Ord. No. 317.[1] Amendments noted where applicable.]

[1] Editor's Note: This ordinance superseded former Ch. 18.20, General Floodplain District (GFP), adopted 10-19-2009 by Ord. No. 255.

§ 18.20.010 General Floodplain District (GFP).

A. Applicability. The provisions for General Floodplain District shall apply to development in all floodplains mapped as A, AO, AH, and in AE Zones within which a floodway is not delineated on the Flood Insurance Rate Maps identified in Section 18.04.050B1.

B. Floodway Boundaries. For proposed development in Zone A, or in Zone AE within which a floodway is not delineated on the Flood Insurance Rate Map identified in Section 18.04.050B1, the boundaries of the regulatory floodway shall be determined pursuant to Section 18.20.010E. If the development is proposed to encroach upon the regulatory floodway, the development is subject to the standards of Ch. 18.12. If the development is located entirely within the floodfringe, the development is subject to the standards of Ch. 18.16.

C. Permitted Uses. Pursuant to Section 18.20.010E, it shall be determined whether the proposed use is located within a floodway or floodfringe area. Those uses permitted in floodway (Section 18.12.020) and floodfringe areas (Section 18.16.020) districts are allowed within the general floodplain district, according to the standards of Section 18.20.010D, provided that all permits or certificates required under Section 18.28.010 have been issued.

D. Standards for Development in the General Floodplain District. Chapter 18.12 applies to floodway areas, determined to pursuant to Section 18.20.010E; Chapter 18.16 applies to floodfringe areas, determined to pursuant to Section 18.20.010E.

1. New construction and substantial improvement of structures in Zone AO shall have the lowest floor, including basement, elevated:

a. To or above the depth, in feet, as shown on the FIRM above the highest adjacent natural grade; or

b. If the depth is not specified on the FIRM, to or above two feet above the highest adjacent natural grade.

2. New construction and substantial improvement of structures in Zone AH shall have the lowest floor, including basement, elevated to or above the flood protection elevation.

3. In AO/AH Zones, provide adequate drainage paths to guide floodwaters around structures.

4. All development in Zone AO and Zone AH shall meet the requirements of Ch. 18.16 applicable to flood fringe areas.

E. Determining Floodway and Floodfringe Limits. Upon receiving an application for development within Zone A, or within Zone AE where a floodway has not been delineated on the Flood Insurance Rate Maps, the Zoning Administrator shall:

1. Require the applicant to submit two copies of an aerial photograph or a plan which shows the proposed development with respect to the general floodplain district limits, stream channel, and existing floodplain developments, along with a legal description of the property, fill limits and elevations, building floor elevations and floodproofing measures; and the flood zone as shown on the FIRM.

2. Require the applicant to furnish any of the following information deemed necessary by the Department (WDNR) to evaluate the effects of the proposal upon flood height and flood flows, regional flood elevation and to determine floodway boundaries:

a. A hydrologic and hydraulic study as specified in Section 18.28.010B3.

b. Plan (surface view) showing elevations or contours of the ground; pertinent structure, fill or storage elevations; size, location and layout of all proposed and existing structures on the site; location and elevations of streets, water supply, and sanitary facilities; soil types and other pertinent information.

c. Specifications for building construction and materials, floodproofing, filling,