Madison General Ordinances ch. 21, subch. 21D — FLOODFRINGE DISTRICT (FF) | Madison General Ordinances (Rev. 28, Update 3: codified through ORD-26-00040, published August 3, 2026) — City of Madison

Madison General Ordinances § 21.15 APPLICABILITY.

21.15 - APPLICABILITY. This section applies to all floodfringe areas shown on the floodplain zoning maps and those identified pursuant to subsection 21.18(5). (Cr. by ORD-25-00012, 3-20-25)

Madison General Ordinances § 21.16 PERMITTED USES.

21.16 - PERMITTED USES. Any structure, land use, or development is allowed in the Floodfringe District (FF) if the standards in subsection 21.17 are met, the use is not prohibited by this, or any other ordinance or regulation and all permits or certificates specified in subsection 21.23 have been issued. (Cr. by ORD-25-00012, 3-20-25)

Madison General Ordinances § 21.17 STANDARDS FOR DEVELOPMENT IN THE FLOODFRINGE.

21.17 - STANDARDS FOR DEVELOPMENT IN THE FLOODFRINGE. Subchapter 21B General Standards shall apply in addition to the following requirements according to the use requested. Any existing structure in the FF District must meet the requirements of subchapter 21F; (1) Residential Uses. Any structure, including a manufactured home, which is to be newly constructed or moved into the FF District, shall meet or exceed the following standards; (a) All new construction, including placement of manufactured homes, and substantial improvement of residential structures, shall have the lowest floor elevated to or above the flood protection elevation on fill. The fill around the structure shall be one foot or more above the regional flood elevation extending at least fifteen (15) feet beyond the limits of the structure. No area may be removed from the FF district unless it can be shown to meet subsection 21.05(5); (b) Notwithstanding subsection 21.17(1)(a), a basement or crawlspace floor may be placed two (2) feet above the regional flood elevation if the basement or crawlspace is designed to make all portions of the structure below the flood protection elevation watertight with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads and effects of buoyancy. No floor of any kind is allowed below the regional flood elevation; (c) Contiguous dryland access shall be provided from a structure to land outside of the floodplain, except as provided in subsection (d) below; (d) In developments where existing street or sewer line elevations make compliance with subd. (c) impractical, the City may permit new development and substantial improvements where roads are below the regional flood elevation, if: 1. The City has written assurance from police, fire and emergency services that rescue, and relief will be provided to the structure(s) by wheeled vehicles during a regional flood event; or 2. The City has a DNR-approved emergency evacuation plan that follows acceptable hazard mitigation planning guidelines. (2) Accessory Structures or Uses. In addition to subchapter 21B General Standards, new construction and substantial improvements of Accessory Structures shall be constructed on fill with the lowest floor at or above the regional flood elevation. (3) Commercial Uses. In addition to subchapter 21B General Standards, any commercial structure which is erected, altered, or moved into the FF District shall meet the requirements of subsection 21.17(1). Subject to the requirements of subsection 21.17(5), storage yards, surface parking lots and other such uses may be placed at lower elevations if an adequate warning system exists to protect life and property. (4) Manufacturing and Industrial Uses. In addition to subchapter 21B General Standards, any manufacturing or industrial structure which is erected, altered, or moved into the FF District shall have the lowest floor elevated to or above the flood protection elevation or meet the floodproofing standards in subsection 21.27. Subject to the requirements of subsection 21.17(5), storage yards, surface parking lots and other such uses may be placed at lower elevations if an adequate warning system exists to protect life and property. (5) Storage of Materials. Materials that are buoyant, flammable, explosive, or injurious to property, water quality or human, animal, plant, fish, or aquatic life shall be stored at or above the flood protection elevation or floodproofed in compliance with subsection 21.27. Adequate measures shall be taken to ensure that such materials will not enter the water body during flooding. (6) Public Utilities, Streets and Bridges. All utilities, streets and bridges shall be designed to be compatible with comprehensive floodplain development plans; and (a) When failure of public utilities, streets and bridges would endanger public health or safety, or where such facilities are deemed essential, construction or repair of such facilities shall only be permitted if they are designed to comply with subsection 21.27. (b) Minor roads or non-essential utilities may be constructed at lower elevations if they are designed to withstand flood forces to the regional flood elevation. (7) Sewage Systems. All sewage disposal systems shall be designed to minimize or eliminate infiltration of flood water into the system, pursuant to subsection 21.27(3), to the flood protection elevation and meet the provisions of all local ordinances and ch. SPS 383, Wis. Adm. Code. (8) Wells. All wells shall be designed to minimize or eliminate infiltration of flood waters into the system, pursuant to subsection 21.27(3), to the flood protection elevation and shall meet the provisions of chs. NR 811 and NR 812, Wis. Adm. Code. (9) Solid Waste Disposal Sites. Disposal of solid or hazardous waste is prohibited in FF District. (10) Deposition of Materials. Any deposited material must meet all the provisions of this ordinance. (11) Manufactured Homes. (a) Owners or operators of all manufactured home parks and subdivisions shall provide adequate surface drainage to minimize flood damage, and prepare, secure approval, and file an evacuation plan, indicating vehicular access and escape routes, with local emergency management authorities. (b) In existing manufactured home parks, all new homes, replacement homes on existing pads, and substantially improved homes shall: 1. Have the lowest floor elevated to the flood protection elevation; and 2. Be anchored so they do not float, collapse, or move laterally during a flood. (c) Outside of existing manufactured home parks, including new manufactured home parks and all single units outside of existing parks, all new, replacement and substantially improved manufactured homes shall meet the residential development standards for the FF District in subsection 21.17(1). (12) Mobile Recreational Vehicles. All mobile recreational vehicles must be on site for less than one hundred and eighty (180) consecutive days and be either: (a) Fully licensed and ready for highway use; or (b) Shall meet the elevation and anchoring requirements in subsection 21.17(11)(b) and (c). A mobile recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick-disconnect utilities and security devices and has no permanently attached additions. (Cr. by ORD-25-00012, 3-20-25)