Current through all regulations passed and filed through September 16, 2024
(A) When a county or municipal corporation
has been notified, pursuant to the requirements of the national flood insurance
program, that it contains areas of special flood hazards (A zones) by the
publication of a FHBM or FIRM, but where such maps neither identify a floodway
or coastal high hazard area, nor contain water surface elevation data, the
county or municipal corporation shall:
(1)
Require permits for all proposed construction and other developments including
the placement of manufactured homes, within Zone A on the FHBM or FIRM;
(2) Review proposed development to
assure that all necessary permits have been received from those governmental
agencies from which approval is required by federal or state law, including
Section 404 of the Federal Water Pollution Control Act Amendments of 1972, 33 U.S.C. 1334 ;
(3) Review all permit
applications to determine whether proposed building sites will be reasonably
safe from flooding. If a proposed building site is in an area of special flood
hazard, all new construction and substantial improvements shall (a) be designed
(or modified) and adequately anchored to prevent flotation, collapse, or
lateral movement of the structure resulting from hydrodynamic and hydrostatic
loads, including the effects of buoyancy, (b) be constructed with materials
resistant to flood damage, (c) be constructed by methods and practices that
minimize flood damages, and (d) be constructed with electrical, heating,
ventilation, plumbing, and air conditioning equipment and other service
facilities that are designed and/or located so as to prevent water from
entering or accumulating within the components during conditions of flooding.
(4) Review subdivision proposals
and other proposed new development, including manufactured home parks or
subdivisions, to determine whether such proposals will be reasonably safe from
flooding. If a subdivision proposal or other proposed new development is in an
area of special flood hazard, any such proposals shall be reviewed to assure
that (a) all such proposals are consistent with the need to minimize flood
damage within the flood-prone area, (b) all public utilities and facilities,
such as sewer, gas, electrical, and water systems are located and constructed
to minimize or eliminate flood damage, and (c) adequate drainage is provided to
reduce exposure to flood hazards;
(5) Require within areas of special flood
hazard new and replacement water supply systems to be designed to minimize or
eliminate infiltration of flood waters into the systems; and
(6) Require within areas of special flood
hazard (a) new and replacement sanitary sewage systems to be designed to
minimize or eliminate infiltration of flood waters into the systems and
discharges from the systems into flood waters and (b) onsite waste disposal
systems to be located to avoid impairment to them or contamination from them
during flooding.
(7) Require that
all new subdivision proposals and other proposed developments (including
proposals for manufactured home parks and subdivisions) greater than fifty lots
or five acres, whichever is the lesser, include within such proposals base
flood elevation data;
(8) Obtain,
review and reasonably utilize any base flood elevation and floodway data
available from a federal, state, or other source, including data developed
pursuant to paragraph (A)(7) of this rule, as criteria for requiring that new
construction, substantial improvements, or other development in Zone A on the
FHBM or FIRM meet the standards in paragraphs (B)(2), (B)(3), (B)(5), (B)(6),
(B)(12), (B)(14), (C)(2) and (C)(3) of this rule;
(9) Where base flood elevation data are
utilized, within Zone A on the FHBM or FIRM:
(a) Obtain the elevation (in relation to mean
sea level) of the lowest floor (including basement) of all new and
substantially improved structures, and
(b) Obtain, if the structure has been
floodproofed in accordance with paragraph (B)(3)(b) of this rule, the elevation
in relation to mean sea level to which the structure was floodproofed, and
(c) Maintain a record of all such
information with the official designated by the county or municipal corporation
to administer the issuance of floodplain development permits.
(10) Notify, in riverine
situations, adjacent counties and municipal corporations prior to any
alteration or relocation of a watercourse, and submit copies of such
notifications to the chief of the division of water in the department of
natural resources.
(11) Assure
that the flood carrying capacity within the altered or relocated portion of any
watercourse is maintained;
(12)
Require that all manufactured homes to be placed within Zone A on the FHBM or
FIRM shall be installed using methods and practices which minimize flood
damage. For the purposes of this requirement, manufactured homes must be
elevated and anchored to resist flotation, collapse or lateral movement. Method
of anchoring may include, but are not to be limited to, use of over-the-top
frame ties to ground anchors. This requirement is in addition to applicable
state and local anchoring requirements for resisting wind forces.
(B) When, pursuant to the
requirements of the national flood insurance program, a county or municipal
corporation has been provided a notice of final flood elevations for one or
more special flood hazard areas on the FIRM and, if appropriate, other special
flood hazard areas have been designated without base flood elevations on the
FIRM, but a regulatory floodway or coastal high hazard area has not been
identified, the county or municipal corporation shall:
(1) Require the standards of paragraph (A) of
this rule within all A1-30 zones, AE zones, A zones, AH zones, and AO zones, on
the FIRM:
(2) Require that all new
construction and substantial improvements of residential structures within
Zones A1-30, AE and AH zones on the FIRM have the lowest floor, including
basement, elevated to or above the base flood level.
(3) Require that all new construction and
substantial improvements of non-residential structures within Zones A1-30, AE
and AH zones on the FIRM (a) have the lowest floor, including basement,
elevated to or above the base flood level or, (b) together with attendant
utility and sanitary facilities, be designed so that below the base flood level
the structure is 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;
(4) Provide that where a non-residential
structure is intended to be made watertight below the base flood level, (a) a
registered professional engineer or architect shall develop and/or review
structural design, specifications, and plans for the construction, and shall
certify that the design and methods of construction are in accordance with
accepted standards of practice for meeting the applicable provisions of
paragraph (B)(3)(b) or (B)(8)(b) of this rule, and (b) a record of such
certificates which includes the specific elevation, in relation to mean sea
level, to which such structures are flood-proofed shall be maintained for
public inspection with the official designated by the county or municipal
corporation.
(5) Require, for all
new construction and substantial improvements, that fully enclosed areas below
the lowest floor that are usable solely for parking of vehicles, building
access or storage in an area other than a basement and which are subject to
flooding shall be designed to automatically equalize hydrostatic flood 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 or exceed the following minimum
criteria: a minimum of two openings having a total net area of not less than
one square inch for every square foot of enclosed area subject to flooding
shall be provided. The bottom of all openings shall be no higher than one foot
above grade. Openings may be equipped with screens, louvers, valves, or other
coverings or devices provided that they permit the automatic entry and exit of
floodwaters.
(6) Require that
manufactured homes that are placed or substantially improved within Zones
A1-30, AH, and AE on the FIRM on sites (a) outside of manufactured home park or
subdivision (b) in a new manufactured home park or subdivision, (c) in an
expansion to an existing manufactured home park or subdivision, or (d) in an
existing manufactured home park or subdivision on which a manufactured home has
incurred "substantial damage" as a result of a flood, be elevated on a
permanent foundation such that the lowest floor of the manufactured home is
elevated to or above the base flood elevation and be securely anchored to an
adequately anchored foundation system to resist flotation collapse and lateral
movement.
(7) Require within any
AO zone on the FIRM that all new construction and substantial improvements of
residential structures 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);
(8) Require within any AO zone on
the FIRM that all new construction and substantial improvements of
nonresidential structures (a) 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 (b) together with attendant utility and sanitary facilities be
completely floodproofed to that level to meet the floodproofing standard
specified in paragraph (B)(3)(b) of this rule;
(9) Require within any A99 zones on a FIRM
the standards of paragraphs (A)(1) to (A)(4)(a) and (A)(9) to (A)(12) of this
rule;
(10) Require until a
regulatory floodway is designated, that no new construction, substantial
improvements, or other development, including fill, shall be permitted within
Zones A1-30 and AE on the FIRM, 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 county or municipal
corporation.
(11) Require within
Zones AH and AO, adequate drainage paths around structures on slopes, to guide
floodwaters around and away from proposed structures.
(12) Require that manufactured homes to be
placed or substantially improved on sites in an existing manufactured home park
or subdivisions within zones A1-30 AH, and AE on the FIRM that are not subject
to the provisions of paragraph (B)(6) of this rule be elevated so that either
(a) the lowest floor of the manufactured home is at or above the base flood
elevation, or (b) the manufactured home chassis is supported by reinforced
piers or other foundation elements of at least equivalent strength that are no
less than thirty-six inches in height above grade and be securely anchored to
an adequately anchored foundation system to resist flotation, collapse, and
lateral movement.
(13)
Notwithstanding any other provisions of this rule, a county or municipality may
approve certain development in Zones A1-30, AE and AH, on the FIRM which
increase the water surface elevation of the base flood by more than one foot,
provided that the county or municipality first applies for approval from the
chief of the division of water in the department of natural resources.
(14) Require that recreational
vehicles placed on sites within Zones A1-30, AH, and AE on the FIRM either (a)
be on the site for fewer than one hundred eighty consecutive days, (b) be fully
licensed and ready for highway use, or (c) meet the permit requirements of
(A)(1) of this rule and the elevation and anchoring requirements for
"manufactured homes" in paragraph (B)(6) of this rule. 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.
(C) When, pursuant to the requirements of the
National Flood Insurance Program, a county or municipal corporation has been
provided a notice of final base flood elevations within Zones A1-30 and/or AE
on the FIRM and, if appropriate, AO zones, AH zones, A99 zones, and A zones
have been designated on the firm, and has been provided data from which the
county or municipal corporation shall designate its regulatory floodway, the
county or municipal corporation shall:
(1)
Meet the requirements of paragraph (B)(1) to (B)(14) of this rule;
(2) 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 any point;
(3) Prohibit encroachments, including fill,
new construction, substantial improvements, and other development within the
adopted regulatory floodway unless it has been demonstrated through hydrologic
and hydraulic analyses performed in accordance with standard engineering
practice that the proposed encroachment would not result in any increase in
flood levels within the county or municipal corporation during the occurrence
of the base flood discharge;
(D) When, pursuant to the requirements of the
national flood insurance program, a county or municipal corporation has been
provided a notice of final base flood elevations within Zones A1-30 and/or AE
on the FIRM and, if appropriate, AH zones, AO zones, A99 zones, and A zones
have been designated on the FIRM, and where on the FIRM coastal high hazard
areas have been designated as Zones V1-30, VE, and/or V, the county or
municipal corporation shall:
(1) Meet the
requirements of paragraphs (B)(1) to (B)(14) of this rule;
(2) Within Zones V1-30, VE, and V on a FIRM.
(a) Obtain the elevation in relation to mean sea level, of the bottom of the
lowest structural member of the lowest floor, excluding pilings and columns, of
all new and substantially improved structures, and whether or not such
structures contain a basement, and (b) maintain a record of all such
information with the official designated by the county or municipal
corporation.
(3) Provide that all
new construction and substantial improvements in Zones V1-30 and VE, and also
Zone V, if base flood elevation data are available, on the FIRM, are elevated
on pilings and columns so that (a) the bottom of the lowest horizontal
structural member of the lowest floor, excluding the pilings or columns, is
elevated to or above the base flood level; and (b) the pile or column
foundation and structure attached thereto is anchored to resist flotation,
collapse and lateral movement due to the effects of wind and water loads acting
simultaneously on all building components. Water loading values used shall be
those associated with the base flood. Wind loading values used shall be those
required by applicable state of local building standards. A registered
professional engineer or architect shall develop or review the structural
design, specifications and plans for the construction, and shall certify that
the design and methods of construction to be used are in accordance with
accepted standards of practice for meeting the provisions of this paragraph.
(4) Provide that all new
construction and substantial improvements within Zones V1-30, VE, and V on the
FIRM have the space below the lowest floor either free of obstruction or
constructed with non-supporting breakaway walls, open wood lattice-work, or
insect screening intended to collapse under wind and water loads without
causing collapse, displacement, or other structural damage to the elevated
portion of the building or supporting foundation system. For the purposes of
this paragraph, a breakaway wall shall have a design safe loading resistance of
not less than ten and no more than twenty pounds per square foot. Use of
breakaway walls which exceed a design safe loading resistance of twenty pounds
per square foot, either by design or when so required by local or state codes,
may be permitted only if a registered professional engineer or architect
certifies that the designs proposed meet the following conditions:
(a) Breakaway wall collapse shall result from
a water load less than that which would occur during the base flood; and,
(b) The elevated portion of the
building and supporting foundation system shall not be subject to collapse,
displacement, or other structural damage due to the effects of wind and water
loads acting simultaneously on all building components-structural and
non-structural. Water loading values used shall be those associated with the
base flood. Wind loading values used shall be those required by applicable
state or local building standards. Such enclosed space shall be useable solely
for parking of vehicles, building access or storage.
(5) Prohibit the use of fill for structural
support of buildings within Zones V1-30, VE, and V on the FIRM;
(6) Require that manufactured homes placed or
substantially improved within Zones V1-30, V, and VE on the FIRM on sites (a)
outside of a manufactured home park or subdivision, (b) in a new manufactured
home park or subdivision, (c) in an expansion to an existing manufactured home
park or subdivision, or (d) in an existing manufactured home park or
subdivision on which a manufactured home has incurred "substantial damage" as
the result of a flood, meet the standards of paragraphs (D)(2) to (D)(5) of
this rule and that manufactured homes placed or substantially improved on other
sites in an existing manufactured home park or subdivision within Zones V1-30,
V, and VE on the FIRM meet the requirements of paragraph (B)(12) of this rule.
(7) Require that recreational
vehicles placed on sites within Zones V1-30, V, and VE on the FIRM either (a)
be on the site for fewer than one hundred eighty consecutive days, (b) be fully
licensed and ready for highway use, or (c) meet the requirements in paragraphs
(A)(1) and (D)(2) to (D)(5) of this rule. 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.