Standards For Development In The Floodway Overlay Zone (FW).
Milwaukee Code of Ordinances § 295-1121
in effect295-1121. Standards For Development In The Floodway Overlay Zone (FW).
1. APPLICABILITY. This section applies to all floodway areas on the floodplain zoning maps and those identified pursuant to s. 295-1127-4.
2. PERMITTED USES. The following open space uses are permitted uses in the floodway overlay zone and the floodway areas of the other floodplain overlay zones if they are not prohibited by any other provision of this code, meet the standards of subs. 2 to 6, and all permits or certificates have been issued according to ss. 295-1129 and 2951131:
a. Agricultural uses, such as farming, outdoor plant nurseries, horticulture, viticulture and wild crop harvesting.
b. Nonstructural industrial and commercial uses, such as loading areas, parking areas and airport landing strips.
c. Nonstructural recreational uses, such as golf courses, tennis courts, archery ranges, picnic grounds, boat ramps, swimming areas, parks, wildlife and nature preserves, game farms, fish hatcheries, shooting, trap and skeet activities, hunting and fishing areas, and hiking and horseback riding trails, subject to the fill limitations of sub. 5.
d. Uses or structures accessory to open space uses or classified as historic structures,that comply with subs. 2 to 6.
e. Extraction of sand, gravel or other materials, subject to sub. 5.
f. Functionally water-dependent uses, such as docks, piers or wharves, dams, flowage areas, culverts, navigational aids, river crossings of transmission lines and pipelines that are in compliance with chs. 30 and 31, Wis. Stats., as amended.
g. Public utilities, streets and bridges that are in compliance with sub. 5.
h. Portable latrines that are removed prior to flooding and systems associated with recreational areas and Wisconsin department of natural resources-approved campgrounds that meet the applicable provisions of this code and ch. SPS 383, Wis. Adm. Code.
i. Public or private wells used to obtain potable water for recreational areas that meet the requirements of this code and chs. NR 811 and NR 812, Wis. Adm. Code.
j. Wastewater treatment ponds or facilities permitted under s. NR 110.15(3)(b), Wis. Adm. Code.
k. Sanitary sewer or water supply lines to service existing or proposed development located outside the floodway that complies with the regulations for the floodplain area occupied.
3. GENERAL DEVELOPMENT STANDARDS. a. Any development in the floodway shall comply with s. 295-1119 and have a low flood damage potential.
b. The applicant shall provide an analysis calculating the effects of the proposal on regional flood height to determine the effects of the proposal according to s. 295-1119 and 295-1129. The analysis shall be completed by a registered professional engineer in the state of Wisconsin.
c. The commissioner shall deny the permit application if the project will cause any increase in the flood elevations upstream or downstream based on the data submitted pursuant to par. b. Any encroachment in the regulatory floodway is prohibited unless the data submitted for par. b demonstrates that the encroachment will cause no increase in flood elevations in flood events up to the base flood at any location or removes the encroached area from the regulatory floodway as provided in s. 295-1141.
d. Parking and loading areas may be at elevations lower than the flood protection elevation. However, no such areas in general use by the public may be inundated to a depth greater than 2 feet or subject to flood velocities greater than 2 feet per second. Such areas may be located at lower elevations if an adequate warning system exists to protect life and property.
4. STRUCTURES. A structure accessory to a permanent open space use, including utility or sanitary facilities, or functionally dependent on a waterfront location may be allowed by permit if the commissioner finds that the structure will comply with all of the following criteria:
a. The structure will not be designed for human habitation, will not have a high flood damage potential and will be constructed to minimize flood damage.
b. The structure will be anchored to resist flotation, collapse and lateral movement.
c. Mechanical and utility equipment will be elevated to or above the flood protection elevation.
d. The structure will not obstruct the flow of flood waters or cause any increase in flood levels during the occurrence of the regional flood.
e.
The structure shall either have the lowest floor elevated to or above the flood protection elevation or meet all of the following standards:
e-1.
Have the lowest floor elevated to or above the regional flood elevation and be dry-floodproofed so that the structure is watertight with walls substantially impermeable to the passage of water and completely dry to the flood protection elevation without human intervention during flooding.
e-2. Have structural components capable of meeting all provisions of par. g.
e-3.
Be certified by a registered professional engineer or architect, through the use of a federal emergency management agency floodproofing certificate, that the design and methods of construction are in accordance with par. g.
f.
For a structure designed to allow the automatic entry of floodwaters below the regional flood elevation, the applicant shall submit a plan that meets pars. a through e and meets or exceeds all of the following standards:
f-1. The lowest floor shall be elevated to or above the regional flood elevation.
f-2.
The structure shall have a minimum of 2 openings having a total net area of not less than one square inch for every one square foot of enclosed area subject to flooding.
f-3.
The bottom of all openings shall be no higher than one foot above the lowest adjacent grade. Openings may be equipped with screens, louvers, valves, or other coverings or devices, provided that they permit the automatic entry and exit of flood waters. If these coverings or devices do not permit automatic entry and exit of flood waters, they shall remain open.
f-4. The use shall be limited to parking, building access or limited storage.
g.
Whenever floodproofing measures are required, a registered professional engineer or architect shall certify that the following floodproofing measures will be utilized, where appropriate, and are adequate to withstand the flood depths, pressures, velocities, impact and uplift forces and other factors associated with the regional flood:
g-1.
Reinforcement of floors and walls to resist rupture, collapse or lateral movement caused by water pressures or debris buildup.
g-2.
Construction of wells, water supply systems and waste treatment systems to prevent the entrance of flood waters in such systems and in accordance with the provisions of sub. 6-b and c.
g-3.
Subsurface drainage systems to relieve external pressures on foundation walls and basement floors.
g-4. Cutoff valves on sewer lines or the elimination of gravity flow basement drains.
g-5. Placement of utilities to or above the flood protection elevation.
5. PUBLIC UTILITIES, STREETS AND BRIDGES. Public utilities, streets and bridges may be allowed by permit if the commissioner finds that both of the following conditions will be met:
a. Adequate floodproofing measures will be provided to the flood protection elevation.
b. The facilities will be constructed in compliance with the development standards of s. 295-1119.
6. FILLS OR DEPOSITION OF MATERIALS. Fills or deposition of materials may be allowed by permit if the commissioner finds that the work to be performed will meet all of the following conditions.
a. The work will be in compliance with the provisions of s. 295-1119.
b. No material will be deposited in navigable waters unless a permit has been issued by the Wisconsin department of natural resources pursuant to ch. 30, Wis. Stats., as amended, a permit has been issued pursuant to s. 404 of the Federal Water Pollution Control Act, Amendments of 1972, 33 U.S.C. 1344, if applicable, and all other requirements have been met.
c. The fill or other materials will be protected against erosion by riprap, vegetative cover, sheet piling or bulkheading.
d. The fill is not classified as a solid or hazardous material.
7. PROHIBITED USES. All uses not listed in sub. 1 are prohibited uses in the floodway overlay zone, including but not limited to:
a. Storage of materials that are buoyant, flammable, explosive or injurious to property, water quality or human, animal, plant, fish or other aquatic life.
b. Any private or public sewage systems, except portable latrines that are removed prior to flooding and systems associated with recreational areas and Wisconsin department of natural resources-approved campgrounds that meet applicable city code provisions and ch. SPS 383, Wis. Adm. Code, as amended.
c. Any public or private wells which are used to obtain potable water, except those for recreational areas that meet applicable city code provisions and the requirements of chs. NR 811 and NR 812, Wis. Adm. Code, as amended.
d. Any solid or hazardous waste disposal sites.
e. Any wastewater treatment ponds or facilities, except those permitted under s. NR 110.15(3)(b), Wis. Adm. Code, as amended.
f. Any sanitary sewer or water supply lines, except those to service existing or proposed development located outside the floodway which complies with the regulations for the floodplain area occupied.
g. Campgrounds.
h. Habitable structures, structures with high flood damage potential, those not associated with permanent open-space uses, and uses not in harmony with or detrimental to uses permitted in the adjoining districts.
Source: City of Milwaukee Legislative Reference Bureau, Milwaukee City Charter and Code of Ordinances (city.milwaukee.gov master PDFs)URL: https://city.milwaukee.gov/ImageLibrary/Groups/ccClerk/Ordinances/Volume-2/CH295-SUB11.pdf#page=11Fetched: 10/26/2026