The standards in this section shall apply to all uses and buildings
that do not conform to the provisions contained within a floodplain
zoning ordinance or with Section 87.30, Wis. Stats. and §§ NR
116.12 through 14, Wis. Adm. Code and 44 CFR 59 through 72, these
standards shall apply to all modifications or additions to any nonconforming
use or structure and to the use of any structure or premises which
was lawful before the passage of this title or any amendment thereto.
A party asserting existence of a lawfully established nonconforming
use or structure has the burden of proving that the use or structure
was compliant with the floodplain zoning ordinance in effect at the
time the use or structure was created.
As permit applications are received for additions, modifications,
or substantial improvements to nonconforming buildings in the floodplain,
municipalities shall develop a list of those nonconforming buildings,
their present equalized assessed value and a list of the costs of
those activities associated with changes to those buildings.
The existing lawful use of a structure or its accessory use which
is not in conformity with the provisions of this title may continue
subject to the following conditions:
No modifications or additions to a nonconforming use or structure
shall be permitted unless they comply with this title. The words "modification"
and "addition" include, but are not limited to, any alteration, addition,
modification, structural repair, rebuilding or replacement of any
such existing use, structure or accessory structure or use. Maintenance
is not considered a modification; these include painting, decorating,
paneling and other nonstructural components and the maintenance, repair
or replacement of existing private sewage or water supply systems
or connections to public utilities. Any costs associated with the
repair of a damaged structure are not considered maintenance. The
construction of a deck that does not exceed 200 square feet and that
is adjacent to the exterior wall of a principal structure is not an
extension, modification or addition. The roof of the structure may
extend over a portion of the deck in order to provide safe ingress
and egress to the principal structure.
If a nonconforming use or the use of a nonconforming structure is
discontinued for 12 consecutive months, it is no longer permitted
and any future use of the property, and any structure or building
thereon, shall conform to the applicable requirements of this title;
The municipality shall keep a record which lists all nonconforming
uses and nonconforming structures, their present equalized assessed
value, the cost of all modifications or additions which have been
permitted, and the percentage of the structure's total current
value those modifications represent;
No modification or addition to any nonconforming structure or any structure with a nonconforming use, which over the life of the structure would equal or exceed 50% of its present equalized assessed value, shall be allowed unless the entire structure is permanently changed to a conforming structure with a conforming use in compliance with the applicable requirements of this title. Contiguous dry land access must be provided for residential and commercial uses in compliance with Section 18.16.030A. The costs of elevating the lowest floor of a nonconforming building or a building with a nonconforming use to the flood protection elevation are excluded from the 50% provisions of this subsection;
No maintenance on a per-event basis to any nonconforming structure or any structure with a nonconforming use, the cost of which would equal or exceed 50% of its present equalized assessed value, shall be allowed unless the entire structure is permanently changed to a conforming structure with a conforming use in compliance with the applicable requirements of this title. Contiguous dry land access must be provided for residential and commercial uses in compliance with Section 18.16.030A. Maintenance to any nonconforming structure, which does not exceed 50% of its present equalized assessed value on a per event basis, does not count against the cumulative calculations over the life of the structure for substantial improvement calculations.
If on a per-event basis the total value of the work being done under Subsection B4 and 5 equals or exceeds 50% of the present equalized assessed value the work shall not be permitted unless the entire structure is permanently changed to a conforming structure with a conforming use in compliance with the applicable requirements of this title. Contiguous dry land access must be provided for residential and commercial uses in compliance with Section 18.16.030A.
Except as provided in Subsection B8, if any nonconforming structure or any structure with a nonconforming use is destroyed or is substantially damaged, it cannot be replaced, reconstructed or rebuilt unless the use and the structure meet the current ordinance requirements. A structure is considered substantially damaged if the total cost to restore the structure to its pre-damaged condition equals or exceeds 50% of the structure's present equalized assessed value.
For nonconforming buildings that are substantially damaged or destroyed
by a nonflood disaster, the repair or reconstruction of any such nonconforming
building shall be permitted in order to restore it to the size and
use in effect prior to the damage event, provided that the following
minimum requirements are met and all required permits have been granted
prior to the start of construction.
Shall have the lowest floor, including basement, elevated to or above the flood protection elevation using fill, pilings, columns, posts or perimeter walls. Perimeter walls must meet the requirements of Section 18.28.050B.
Shall be anchored to prevent flotation, collapse, or lateral
movement of the structure resulting from hydrodynamic and hydrostatic
loads, including the effects of buoyancy and shall be constructed
with methods and materials resistant to flood damage.
Shall be constructed with electrical, heating,
ventilation, plumbing and air conditioning equipment and other service
facilities that are designed and/or elevated so as to prevent water
from entering or accumulating within the components during conditions
of flooding.
Shall either have the lowest floor, including basement, elevated to or above the regional flood elevation; or, together with attendant utility and sanitary facilities, shall meet the standards in Section 18.28.050A or B.
A nonconforming historic structure may be altered if the alteration will not preclude the structure's continued designation as a historic structure, the alteration will comply with Section 18.12.030A, flood-resistant materials are used, and construction practices and floodproofing methods that comply with Section 18.28.050 are used. Repair or rehabilitation of historic structures shall be exempt from the development standards of Section 18.24.010B8a if it is determined that the proposed repair or rehabilitation will not preclude the structure's continued designation as a historic structure and is the minimum necessary to preserve the historic character and design of the structure.
Notwithstanding anything in this chapter to the contrary, modifications,
additions, maintenance, and repairs to a nonconforming building shall
not be prohibited based on cost and the building's nonconforming
use shall be permitted to continue if:
If the nonconforming building is in the floodway, the building is permanently changed to conform to the applicable requirements of Sections 18.12.030A, B2 through 5, C, D, and 18.24.020; or
If the nonconforming building is in the floodfringe, the building is permanently changed to conform to the applicable requirements of Sections 18.16.030 and 18.24.030.
New construction and substantial improvements of residential buildings
in Zones A1-30, AE, and AH must have the lowest floor (including basement)
elevated to or above the base flood elevation.
New construction and substantial improvements of nonresidential buildings
in Zones A1-30, AE, and AH must have the lowest floor (including basement)
elevated to or above the base flood elevation, or (together with attendant
utility and sanitary facilities) be designed so that below the base
flood elevation the building is watertight with walls substantially
impermeable to the passage of water and with structural components
capable of resisting hydrostatic and hydrodynamic loads and effects
of buoyancy.
Where a nonresidential structure is intended to be made watertight below the base flood elevation, a registered professional engineer or architect must develop and/or review structural design, specifications, and plans for the construction, and must certify that the design and methods of construction are in accordance with accepted standards of practice for meeting the provisions of Section 18.24.010D7 above.
Fully enclosed areas below the lowest floor of new construction and
substantial improvements in Zones A1-30, AE, and AH that are usable
solely for parking of vehicles, building access, or storage, must
be designed to adequately equalize hydrostatic forces on exterior
walls by allowing for the entry and exit of floodwaters. Designs for
meeting this requirement must either be certified by a registered
professional engineer or architect, or meet the following criteria:
A minimum of two openings into each enclosed area must be located
below the base flood elevation and provide a total net area of not
less than one square inch for every square foot of enclosed area;
Manufactured homes that are placed or substantially improved within
Zones A1-30, AE, and AH outside of a manufactured home park or subdivision,
in a new manufactured home park or subdivision, in an expansion to
an existing manufactured home park or subdivision, or in an existing
manufactured home park or subdivision on which a manufactured home
has incurred substantial damage as a result of flood, must be elevated
on a permanent foundation such that the lowest floor of the manufactured
home is at or above the base flood elevation, and be securely anchored
to an adequately anchored foundation system to resist flotation, collapse,
and lateral movement.
Manufactured homes that are placed or substantially improved
within Zones A1-30, AE, and AH on existing sites in an existing manufactured
home park that is not undergoing expansion and on which a manufactured
home has not incurred substantial damage as a result of flood must
be elevated so that either the lowest floor of the manufactured home
is at or above the base flood elevation, or the manufactured home
chassis is supported by reinforced piers or other foundation elements
of at least equivalent strength that are no less than 36 inches in
height above grade, and be securely anchored to an adequately anchored
foundation system to resist flotation, collapse, and lateral movement.
Be fully licensed and ready for highway use (a 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 type utilities
and security devices, and has no permanently attached additions);
or
In a regulatory floodway that has been delineated on the FIRM
in Zone A1-30 or AE, encroachments, including new construction, substantial
improvement, or other development (including fill) must be prohibited
unless it has been demonstrated through hydrologic and hydraulic analyses
performed in accordance with standard engineering practice that the
proposed encroachment will not result in any increase in flood levels
within the community during the occurrence of the base flood discharge.
In Zone A, the community must obtain, review, and reasonably utilize any base flood elevation and floodway data available from a federal, state, or other source as criteria for requiring new construction, substantial improvement, and other development to meet Section 18.24.010D5 through 12 (inclusive) above. If floodway data are available, the community must select and adopt a regulatory floodway based on the principle that the area chosen for the regulatory floodway must be designed to carry the waters of the base flood without increasing the water surface elevation of that flood more than one foot at any point.
In Zones A1-30 or AE where a regulatory floodway has not been
delineated on the FIRM, no new construction, substantial improvement,
or other development (including fill) may be permitted unless it is
demonstrated that the cumulative effect of the proposed development,
when combined with all other existing and anticipated development,
will not increase the water surface elevation of the base flood more
than one foot at any point within the community.
Notwithstanding the requirements of § 18.24.010D12 and 14 above, the community may permit certain development in Zones A1-30 and AE where a floodway has not been delineated, which will increase the water surface elevation of the base flood by more than one foot, or in a regulatory floodway, which will result in an increase in base flood elevations, if the community first obtains a Conditional Letter of Map Revision (CLOMR) from FEMA and fulfills the requirements of 44 CFR 65.12.
In Zone AO, new construction and substantial improvements of
residential structures must have the lowest floor (including basement)
elevated above the highest adjacent grade at least as high as the
depth number specified in feet on the FIRM (at least two feet if no
depth number is specified).
In Zone AO, new construction and substantial improvements of nonresidential structures must have the lowest floor (including basement) elevated above the highest adjacent grade at least as high as the depth number specified in feet on the FIRM (at least two feet if no depth number is specified), or (together with attendant utility and sanitary facilities) be structurally dry-floodproofed to that level according to the standard specified in Section 18.24.010D7 above.
No modification or addition shall be allowed to any nonconforming
structure or any structure with a nonconforming use in a floodway
district, unless such modification or addition:
Any addition to the existing structure shall be floodproofed, pursuant to Section 18.28.050 by means other than the use of fill, to the flood protection elevation; and
The enclosed area shall be designed by a registered architect
or engineer to allow for the efficient entry and exit of flood waters
without human intervention. A minimum of two openings must be provided
with a minimum net area of at least one square inch for every one
square foot of the enclosed area. The lowest part of the opening can
be no more than 12 inches above the adjacent grade;
No new on-site sewage disposal system, or addition to an existing on-site sewage disposal system, except where an addition has been ordered by a government agency to correct a hazard to public health, shall be allowed in a floodway district. Any replacement, repair or maintenance of an existing on-site sewage disposal system in a floodway area shall meet the applicable requirements of all municipal ordinances, Section 18.28.050C and Ch. SPS 383, Wis. Adm. Code.
No new well or modification to an existing well used to obtain potable water shall be allowed in the floodway district. Any replacement, repair or maintenance of an existing well in a floodway area shall meet the applicable requirements of all municipal ordinances, Section 18.28.050C and Chs. NR 811 and NR 812, Wis. Adm. Code.
No modification or addition shall be allowed to any nonconforming structure or any structure with a nonconforming use unless such modification or addition has been granted a permit or variance by the municipality, and meets the requirements of Section 18.16.030, except where Section 18.24.030B is applicable.
Where compliance with the provisions of Subsection A would result in unnecessary hardship and only where the structure will not be used for human habitation or be associated with a high flood damage potential, the Board of Adjustment/Appeals, using the procedures established in Section 18.28.030, may grant a variance from those provisions of Subsection A for modifications or additions, using the criteria listed below. Modifications or additions which are protected to elevations lower than the flood protection elevation may be permitted if:
All new private sewage disposal systems, or addition to, replacement,
repair or maintenance of a private sewage disposal system shall meet
all the applicable provisions of all local ordinances and Section
18.28.050E and Ch. SPS 383, Wis. Adm. Code.
All new wells, or addition to, replacement, repair or maintenance
of a well shall meet the applicable provisions of this title, Section
18.28.050E and Chs. NR 811 and NR 812, Wis. Adm. Code.