[HISTORY: Adopted by the Board of Commissioners
of the City of Millville 12-18-2001 by Ord. No. 43-2001;[1] amended in its entirety 6-7-2016 by Ord. No. 22-2016.
Subsequent amendments noted where applicable.]
GENERAL REFERENCES
Land use and development regulations — See Ch. 30.
[1]
Editor's Note: This ordinance also superseded former Ch. 20,
Flood Hazard Protection, adopted 3-20-1990 as Ch. XIV of the Revised
General Ordinances of the City of Millville 1989.
Pursuant to N.J.S.A. 40:48-1 et seq., the Legislature of the
State of New Jersey has delegated the responsibility to local government
to adopt regulations designed to promote the public health, safety
and general welfare of its citizenry.
A.
The
flood hazard areas of the City of Millville are subject to periodic
inundation which results in health and safety hazards, loss of property,
disruption of commerce and governmental services, extraordinary public
expenditures for flood protection and relief and impairment of services,
extraordinary public expenditures for flood protection and relief
and impairment of the tax base, all of which adversely affect the
public health, safety and general welfare.
B.
These
flood losses are caused by the cumulative effect of obstructions in
areas of special flood hazard which increase flood heights and velocities
and, when inadequately anchored, damage uses in other areas. Uses
that are inadequately floodproofed, elevated or otherwise protected
from flood damage also contribute to the flood loss.
It is the purpose of this chapter to promote the public health,
safety and general welfare and to minimize public and private losses
due to flood conditions in specific areas by provisions designed to:
A.
Protect
human life and health.
B.
Minimize
expenditure of public money for costly flood control projects.
C.
Minimize
the need for rescue and relief efforts associated with flooding and
generally undertaken at the expense of the general public.
D.
Minimize
prolonged business interruptions.
E.
Minimize
damage to public facilities and utilities such as sewer and water
mains, electric, gas and telephone lines, bridges and streets located
in the areas of special flood hazard.
F.
Help
maintain a stable tax base by providing for the proper use and development
of areas of special flood hazard so as to minimize future flood blight
areas.
G.
Ensure
that potential buyers are notified that property is in an area of
special flood hazard.
H.
Ensure
that those who occupy the areas of special flood hazard assume responsibility
for their actions.
I.
To maintain eligibility and good standing in the National Flood Insurance
Program enabling residents to purchase flood insurance, which would
otherwise be unavailable.
In order to accomplish its purposes, this chapter includes methods
and provisions for:
A.
Restricting
or prohibiting uses which are dangerous to health, safety and property
due to water or erosion hazards or which result in damaging increases
in erosion or in flood heights or velocities.
B.
Requiring
that uses vulnerable to floods, including facilities which serve such
uses, be protected against flood damage at the time of initial construction.
C.
Controlling
the alteration of natural floodplains, stream channels and natural
protective barriers, which help accommodate or channel floodwaters.
D.
Controlling
dredging, filling, grading and other development which may increase
flood damage.
E.
Preventing
or regulating the construction of flood barriers which will unnaturally
divert floodwaters or which may increase flood hazards in other areas.
As used in this chapter, the following terms shall have the
following meanings unless the context clearly indicates that a different
meaning is intended:
A request for a review of the Construction Official's
interpretation of any provision of this chapter or a request for a
variance.
The land in the floodplain within a community subject to
a one-percent-or-greater chance of flooding in any given year. It
is shown on the FIRM as Zone A or AE.
The flood having a one-percent chance of being equaled or
exceeded in any given year (one-hundred-year flood).
The flood elevation shown on a published Flood Insurance
Study (FIS) including the Flood Insurance Rate Map (FIRM). For zone
AE, the elevation represents the water surface elevation resulting
from a flood that has a one-percent-or-greater chance of being equaled
or exceeded in any given year.
Any area of the building having its floor subgrade (below
ground level) on all sides.
A wall that is not part of the structural support of the
building and is intended through its design and construction to collapse
under specific lateral loading forces without causing damage to the
elevated portion of the building or supporting foundation system.
The portion of the Special Flood Hazard Area (SFHA) starting
from a Velocity (V) Zone and extending up to the landward Limit of
the Moderate Wave Action delineation. Where no V Zone is mapped the
Coastal A Zone is the portion between the open coast and the landward
Limit of the Moderate Wave Action delineation. Coastal A Zones may
be subject to wave effects, velocity flows, erosion, scour, or a combination
of these forces. Construction and development in Coastal A Zones is
to be regulated the same as V Zones/coastal high hazard areas.
Any made-made change to improved or unimproved real estate,
including but not limited to buildings or other structures, mining,
dredging, filling, grading, paving, excavation or drilling operations
or storage of equipment or materials located within the area of special
flood hazard.
The official map on which the Federal Insurance Administration
has delineated both the areas of special flood hazards and the risk
premium zones applicable to the community.
A nonbasement building which is built, in the case of a building
in an area of special flood hazard, to have the top of the elevated
floor or, in the case of a building in a Coastal A Zone, to have the
bottom of the lowest horizontal structural member of the elevated
floor, elevated above the base flood elevation plus freeboard by means
of pilings, columns (posts and piers) or shear walls parallel to the
flow of the water, and which is adequately anchored so as not to impair
the structural integrity of the building during a flood up to the
magnitude of the base flood. In an area of special flood hazard, "elevated
building" also includes a building elevated by means of fill or solid
foundation perimeter walls with openings sufficient to facilitate
the unimpeded movement of floodwaters. In Areas of Coastal A Zones,
"elevated buildings" also includes a building otherwise meeting the
definition of "elevated building" even though the lower area is enclosed
by means of breakaway walls.
The process of the gradual wearing away of land masses.
A manufactured home park or subdivision for which the construction
of facilities for servicing the lots on which the manufactured homes
are to be affixed (including, at a minimum, the installation of utilities,
the construction of streets, and either final site grading or the
pouring of concrete pads) is completed before the effective date of
the floodplain management regulations adopted by a community.
The official map on which the Federal Insurance Administration
has delineated both the areas of special flood hazard and the risk
premium zones applicable to the community.
The official report provided in which the Federal Insurance
Administration has provided flood profiles, as well as the Flood Boundary/Floodway
Map and the water surface elevation of the base flood.
A general and temporary condition of partial or complete
inundation of normally dry land areas from:
Zoning ordinances, subdivision regulations, building codes,
health regulations, special purpose ordinances (such as a floodplain
ordinance, grading ordinance and erosion control ordinance) and other
applications of police power. The term describes such state or local
regulations, in any combination thereof, which provide standards for
the purpose of flood damage prevention and reduction.
Any combination of structural and nonstructural additions,
changes, or adjustments to structures which reduce or eliminate flood
damage to real estate or improved real property, water and sanitary
facilities, structures and their contents.
The channel of a river or other watercourse and the adjacent
land areas that must be reserved in order to discharge the base flood
without cumulatively increasing the water surface elevation more than
0.2 foot.
A factor of safety usually expressed in feet above a flood
level for purposes of floodplain management. "Freeboard" tends to
compensate for the many unknown factors that could contribute to flood
heights greater than the height calculated for a selected size flood
and floodway conditions, such as wave action, bridge openings, and
the hydrological effect of urbanization of the watershed.
The highest natural elevation of the ground surface prior
to construction next to the proposed or existing walls of a structure.
Any structure that is:
Listed individually in the National Register of Historic Places
(a listing maintained by the Department of the Interior) or preliminarily
determined by the Secretary of the Interior as meeting the requirements
for individual listing on the National Register;
Certified or preliminarily determined by the Secretary of the
Interior as contributing to the historical significance of a registered
historic district or a district preliminarily determined by the Secretary
to qualify as a registered historic district;
Individually listed on a state inventory of historic places
in states with historic preservation programs which have been approved
by the Secretary of the Interior; or
Individually listed on a local inventory of historic places
in communities with historic preservation programs that have been
certified either:
Inland limit of the area affected by waves greater than 1.5
feet during the base flood. Base flood conditions between the V Zone
and the LiMWA will be similar to, but less severe than, those in the
V Zone.
The lowest floor of the lowest enclosed area (including basement).
An unfinished or flood-resistant enclosure, usable solely for the
parking of vehicles, building access or storage in an area other than
a basement, is not considered a building's lowest floor, provided
that such enclosure is not built so to render the structure in violation
of other applicable nonelevation design requirements of 44 CFR 60.3.
A structure, transportable in one or more sections, which
is built on a permanent chassis and is designed for use with or without
a permanent foundation when attached to the required utilities. The
term "manufactured home" does not include a recreational vehicle.
A parcel (or contiguous parcels) of land divided into two
or more manufactured home lots for rent or sale.
Structures for which the start of construction commenced
on or after the effective date of a floodplain regulation adopted
by a community, and includes any subsequent improvements to such structures.
A manufactured home park or subdivision for which the construction
of facilities for servicing the lots on which the manufactured homes
are to be affixed (including, at a minimum, the installation of utilities,
the construction of streets and either final site grading or the pouring
of concrete pads) is completed on or after the effective date of the
floodplain management regulations adopted by the municipality.
A vehicle which is:
Built on a single chassis;
Four hundred square feet or less when measured at the longest
horizontal projections;
Designed to be self-propelled or permanently towable by light-duty
truck; and
Designed primarily not for use as a permanent dwelling but as
a temporary living quarters for recreational, camping, travel or seasonal
use.
For other than new construction or substantial improvements
under the Coastal Barrier Resources Act (P.L. No. 97-348)[1] includes substantial improvements and means the date the
building permit was issued, provided that the actual start of construction,
repair, reconstruction, rehabilitation, addition, placement or other
improvement was within 180 days of the permit date. The "actual start"
means either the first placement of permanent construction of a structure
on a site, such as the pouring of a slab or footings, the installation
of piles, the construction of columns or any work beyond the stage
of excavation, or the placement of a manufactured home on a foundation.
Permanent construction does not include land preparation, such as
clearing, grading and filling; nor does it include the installation
of streets and/or walkways; nor does it include excavation for a basement,
footings or piers or foundations or the erection of temporary forms;
nor does it include the installation on the property of accessory
buildings, such as garages or sheds, not occupied as dwelling units
or not part of the main structure. For a substantial improvement,
the "actual start of construction" means the first alteration of any
wall, ceiling, floor or other structural part of a building, whether
or not that alteration affects the external dimensions of the building.
A walled and roofed building, a manufactured home or a gas
or liquid storage tank that is principally aboveground.
Damage of any origin sustained by a structure whereby the
cost of restoring the structure to its before-damaged condition would
equal or exceed 50% of the market value of the structure before the
damage occurred.
Any reconstruction, rehabilitation, addition or other improvement
of a structure, the cost of which equals or exceeds 50% of the market
value of the structure before the start of construction of the improvement.
This term includes structures which have incurred substantial damage,
regardless of the actual repair work performed. The term does not,
however, include either:
Any project for improvement of a structure to correct existing
violations of state or local health, sanitary or safety code specifications
which have been identified by the local code enforcement officer and
which are the minimum necessary to assure safe living conditions;
or
Any alteration of an historic structure, provided that the alteration
will not preclude the structure's continued designation as an
historic structure.
A grant of relief from the requirements of this chapter which
permits construction in a manner that would otherwise be prohibited
by this chapter.
The failure of a structure or other development to be fully
compliant with this chapter. A new or substantially improved structure
or other development without the elevation certificate, other certifications,
or other evidence of compliance required in 44 CFR 60.3(b)(5), (c)(4),
(c)(10), (e)(2), (e)(4) or (e)(5) is presumed to be in violation until
such time as that documentation is provided.
[1]
Editor's Note: See 16 U.S.C. § 3501 et seq.
This chapter shall apply to all areas of special flood hazard
within the jurisdiction of the City of Millville.
The areas of special flood hazard identified by the Federal
Emergency Management Agency in a scientific and engineering report
titled the "Flood Insurance Study, Volume 1 of 1, Cumberland County,
New Jersey (All Jurisdictions)," dated June 16, 2016, with accompanying
Flood Insurance Rate Map (FIRM) Panel Nos. 34011C0170E, 34011C0178E,
34011C0179E, 34011C0183E, 34011C0187E, 34011C0189E, 34011C0190E, 34011C0191E,
34011C0192E, 34011C0193E, 34011C0194E, 34011C0213E, 34011C0214E, 34011C0330E,
34011C0331E, 34011C0332E, 34011C0333E, 34011C0334E, 34011C0351E and
34011C0352E, dated June 16, 2016, is hereby adopted by reference and
declared to be a part of this chapter. The Flood Insurance Study and
FIRM panels are on file in the office of the City Clerk, 12 South
High Street, Millville, New Jersey.
A.
No
land or structure shall hereafter be altered, constructed, converted,
extended, relocated to or located without full compliance with the
terms of this chapter and other applicable regulations. Violation
of the provisions of this chapter by failure to comply with any of
its requirements (including violations of conditions and safeguards
established in connection with condition) shall constitute a misdemeanor.
B.
Any
person who violates this chapter or fails to comply with any of its
requirements shall, upon conviction thereof, be fined not more than
$1,000 or imprisoned for not more than 90 days, or both, for each
violation and, in addition, shall pay all costs and expenses involved
in the case.
C.
Nothing
herein contained shall prevent the City of Millville from taking such
other lawful action as is necessary to prevent or remedy any violation.
This chapter is not intended to abrogate, impair, or repeal
any existing covenants, deed restrictions, or easements. However,
where this chapter and another ordinance, covenant, deed restriction,
or easement conflict or overlap, whichever imposes the more stringent
restrictions shall prevail.
In the interpretation and application of this chapter, all provisions
shall be:
A.
The degree of flood protection required by this chapter is considered
reasonable for regulatory purposes and is based on scientific and
engineering considerations. Larger floods can and will occur on rare
occasions. Flood heights may be increased by man-made or natural causes.
This chapter does not imply that land outside the areas of special
flood hazard or uses permitted within such areas will be free from
flooding or flood damage.
B.
This chapter shall not create liability on the part of the City of
Millville, any officer or employee thereof, or the Federal Insurance
Administration for any flood damages that result from reliance on
this chapter or any administrative decision lawfully made thereunder.
A.
A development permit shall be obtained before construction or development begins within any area of special flood hazard established in § 20-7. Application for a development permit shall be made on forms furnished by the Construction Official and may include but not be limited to plans, in duplicate, drawn to scale showing the nature, location, dimensions and elevations of the area in question; existing or proposed structures, fill, storage of materials and drainage facilities; and the location of the foregoing.
B.
Specifically, the following information is required:
(1)
Elevation, in relation to mean sea level, of the lowest floor (including
basement) of all structures.
(2)
Elevation, in relation to mean sea level, to which any structure
has been floodproofed.
(3)
Certification by a registered professional engineer or architect that the floodproofing methods for any nonresidential structure meet the floodproofing criteria in § 20-17B.
(4)
Description of the extent to which any watercourse will be altered
or relocated as a result of proposed development.
The Construction Official is hereby appointed to administer
and implement this chapter by granting or denying development permit
applications in accordance with its provisions.
The duties of the Construction Official shall include but not
be limited to:
A.
Permit review.
(1)
Review all development permits to determine that the permit requirements
of this chapter have been satisfied.
(2)
Review all development permits to determine that all necessary permits
have been obtained from federal, state or local governmental agencies
from which prior approval is required.
(3)
Review all development permits to determine if the proposed development is located in the floodway and assure that the encroachment provisions of § 20-18A are met.
(4)
Review all development permits in the Coastal A Zone area of the
area of special flood hazard to determine if the proposed development
alters the terrain so as to increase potential flood damage.
B.
Use of other base flood and floodway data. When base flood elevation and floodway data have not been provided in accordance with § 20-7, Basis for establishing areas of special flood hazard, the Construction Official shall obtain, review and reasonably utilize any base flood elevation and floodway data available from a federal, state or other source in order to administer § 20-17A, Residential construction, and § 20-17B, Nonresidential construction.
C.
Information to be obtained and maintained.
(1)
Obtain and record the actual elevation in relation to mean sea level
of the lowest floor (including basement) of all new or substantially
improved structures, and whether or not the structure contains a basement.
(4)
Maintain for public inspection all records pertaining to the provisions
of this chapter.
D.
Alteration of watercourses.
(1)
Notify adjacent communities and the New Jersey Department of Environmental
Protection, Dam Safety and Flood Control Section and the Land Use
Regulation Program prior to any alteration or relocation of a watercourse,
and submit evidence of such notification to the Federal Insurance
Administration.
(2)
Require that maintenance is provided within the altered relocated
portion of said watercourse so that the flood-carrying capacity is
not diminished.
E.
Substantial damage review.
(1)
After an event resulting in building damages, assess the damage to
structures due to flood and nonflood causes.
(2)
Record and maintain the flood and nonflood damage of substantial
damage structures and provide a letter of substantial damage determination
to the owner and the New Jersey Department of Environmental Protection,
Dam Safety and Flood Control Section.
F.
Interpretation of FIRM boundaries. The Construction Official shall make interpretations where needed as to the exact location of the boundaries of the areas of special flood hazard (for example, where there appears to be a conflict between a mapped boundary and actual field conditions). The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as provided in § 20-15.
A.
Appeals Board.
(1)
The Cumberland County Construction Appeals Board as established by
the County of Cumberland shall hear and decide appeals and requests
for variances from the requirements of this chapter.
(2)
The Cumberland County Construction Appeals Board shall hear and decide
appeals when it is alleged there is an error in any decision, determination
or requirement made by the Construction Official in the administration
or enforcement of this chapter.
(3)
Those aggrieved by the decision of the Appeals Board, or any taxpayer,
may appeal such decision to the Superior Court, as provided by law.
(4)
In passing upon such applications, the Appeals Board shall consider
all technical evaluations, all relevant factors, standards specified
in other sections of this chapter, and:
(a)
The danger that materials may be swept onto other lands to the
injury of others.
(b)
The danger to life and property due to flooding or erosion damage.
(c)
The susceptibility of the proposed facility and its contents
to flood damage and the effect of such damage on the individual owner.
(d)
The importance of the services provided by the proposed facility
to the community.
(e)
The necessity to the facility of a waterfront location, where
applicable.
(f)
The availability of alternative locations for the proposed use
which are not subject to flooding or erosion damage.
(g)
The compatibility of the proposed use with existing and anticipated
development.
(h)
The relationship of the proposed use to the Comprehensive Plan
and floodplain management program of that area.
(i)
The safety of access to the property in times of flood for ordinary
and emergency vehicles.
(j)
The expected heights, velocity, duration, rate of rise and sediment
transport of the floodwaters and the effects of wave action, if applicable,
expected at the site.
(k)
The cost of providing governmental services during and after
flood conditions, including maintenance and repair of public utilities
and facilities such as sewer, gas, electrical and water systems and
streets and bridges.
(5)
Upon consideration of the factors of Subsection A(4) above and the purposes of this chapter, the Appeals Board may attach such conditions to the granting of variances as it deems necessary to further the purposes of this chapter.
(6)
The Construction Official shall maintain the records of all appeal
actions, including technical information, and report any variances
to the Federal Insurance Administration upon request.
B.
Conditions for variances.
(1)
Generally, variances may be issued for new construction and substantial improvements to be erected on a lot of 1/2 acre or less in size contiguous to and surrounded by lots with existing structures constructed below the base flood level, provided that the items in Subsection A(4)(a) through (k) above have been fully considered. As the lot size increases beyond the 1/2 acre, the technical justification required for issuing the variance increases.
(2)
Variances may be issued for the repair or rehabilitation of historic
structures upon a determination that the proposed repair or rehabilitation
will not preclude the structure's continued designation as an
historic structure and the variance is the minimum necessary to preserve
the historic character and design of the structure.
(3)
Variances shall not be issued within any designated floodway if any
increase in flood levels during the base flood discharge would result.
(4)
Variances shall only be issued upon a determination that the variance
is the minimum necessary, considering the flood hazard, to afford
relief.
(5)
Variance shall only be issued upon:
(a)
A showing of good and sufficient cause;
(b)
A determination that failure to grant the variance would result
in exceptional hardship to the applicant; and
(c)
A determination that the granting of a variance will not result in increased flood heights, additional threats to public safety or extraordinary public expense or create nuisances or cause fraud on or victimization of the public as identified in Subsection A(4) above or conflict with existing local laws or ordinance.
(6)
Any applicant to whom a variance is granted shall be given written
notice that the structure will be permitted to be built with a lowest
floor elevation below the base flood elevation and the cost of flood
insurance will be commensurate with the increased risk resulting from
the reduced lowest floor elevation.
In all areas of special flood hazards, compliance with the applicable
requirements of the Uniform Construction Code (N.J.A.C. 5:23) and
the following standards, whichever is more restrictive, is required:
A.
Anchoring.
(1)
All new construction and substantial improvements shall be anchored
to prevent flotation, collapse or lateral movement of the structure.
(2)
All manufactured homes to be placed or substantially improved shall
be anchored to resist flotation, collapse or lateral movement. Methods
of anchoring may include but are not to be limited to use of over-the-top
or frame ties to ground anchors. This requirement is in addition to
applicable state and local anchoring requirements for resisting wind
force.
B.
Construction materials and methods.
C.
Utilities.
(1)
All new and replacement water supply systems shall be designed to
minimize or eliminate infiltration of floodwaters into the system.
(2)
New and replacement sanitary sewage systems shall be designed to
minimize or eliminate infiltration of floodwaters into the systems
and discharge from the systems into floodwaters.
(3)
On-site waste disposal systems shall be located to avoid impairment
to them or contamination from them during flooding.
(4)
For all new construction and substantial improvements the electrical,
heating, ventilation, plumbing and air-conditioning equipment and
other service facilities shall be designed and/or located so as to
prevent water from entering or accumulating within components during
conditions of flooding.
D.
Subdivision proposals.
(1)
All subdivision proposals and other proposed new development shall
be consistent with the need to minimize flood damage.
(2)
All subdivision proposals and other proposed new development shall
have public utilities and facilities such as sewer, gas, electrical
and water systems located and constructed to minimize flood damage.
(3)
All subdivision proposals and other proposed new development shall
have adequate drainage provided to reduce exposure to flood damage;
and
(4)
Base flood elevation data shall be provided for subdivision proposals
and other proposed new development which contain at least 50 lots
or five acres (whichever is less).
E.
Enclosure openings. For all new construction and substantial improvements,
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 must meet or exceed the following minimum
criteria:
(1)
A minimum of two openings in at least two exterior walls of each
enclosed area, 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.
(2)
The bottom of all openings shall be no higher than one foot above
grade.
(3)
Openings may be equipped with screens, louvers or other covering
devices, provided that they permit the automatic entry and exit of
floodwaters.
In all areas of special flood hazard where base flood elevation data have been provided as set forth in § 20-7, Basis for establishing areas of special flood hazard, or in § 20-14B, Use of other base flood and floodway data, the following standards are required:
A.
Residential construction.
(2)
New construction and substantial improvement of any residential structure
located in an A or AE Zone shall have the lowest floor, including
basement together with the attendant utilities and sanitary facilities,
elevated to or above base flood elevation plus one foot or as required
by ASCE/SEI 24-14, Table 2-1, whichever is more restrictive.
B.
Nonresidential construction. In an area of special flood hazard, all new construction and substantial improvement of any commercial, industrial, or other nonresidential structure located in an A or AE Zone (for Coastal A Zone construction see § 20-19, Coastal A Zone) shall have the lowest floor, including basement together with the attendant utilities and sanitary facilities: either
(1)
Elevated to or above the base flood elevation plus one foot or as
required by ASCE/SEI 24-14, Table 2-1, whichever is more restrictive;
or
(2)
Be floodproofed so that below the base flood level plus one foot
or as required by ASCE/SEI 24-14, Table 6-1, whichever is more restrictive,
the structure is watertight with walls substantially impermeable to
the passage of water;
(3)
Have structural components capable of resisting hydrostatic and hydrodynamic
loads and effects of buoyancy; and
(4)
Be certified by a registered professional engineer or architect that the design and methods of construction are in accordance with accepted standards of practice for meeting the applicable provisions of this subsection. Such certification shall be provided to the official as set forth in § 20-14C(2)(b).
C.
Manufactured homes.
(2)
All manufactured homes to be placed or substantially improved within
an area of special flood hazard shall:
(a)
Be consistent with the need to minimize flood damage;
(b)
Be constructed as to minimize flood damage;
(c)
Have adequate drainage provided to reduce exposure to flood
damage; and
(d)
Be elevated on a permanent foundation such that the top of the
lowest floor is at or above the base flood elevation plus one foot
or as required by ASCE/SEI 24-14, Table 2-1, whichever is more restrictive.
Located within areas of special flood hazard established in § 20-7 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of floodwaters which carry debris, potential projectiles and erosion potential, the following provisions apply:
A.
Encroachment, including fill, new construction, substantial improvements
and other development, shall be prohibited unless a technical evaluation
demonstrates that encroachment shall not result in any increase in
flood levels during the occurrence of the base flood discharge.
C.
In all areas of special flood hazard in which base flood elevation
data has been provided and no floodway has been designated, the cumulative
effect of any proposed development, when combined with all other existing
and anticipated development, shall not increase the water surface
elevation of the base flood more than 0.2 of a foot at any point.
Coastal A Zones are located within the areas of special flood hazard established in § 20-7. These areas may be subject to wave effects, velocity flows, erosion, scour, or a combination of these forces; therefore, the following provisions shall apply:
B.
Construction methods.
(1)
Elevation. All new construction and substantial improvements shall
be elevated on piling or columns so that:
(a)
The bottom of the lowest horizontal structural member of the
lowest floor (excluding the piling or columns) is elevated to or above
the base flood elevation plus one foot or as required by ASCE/SEI
24-14, Table 4-1, whichever is more restrictive; and
(2)
Structural support.
(a)
All new construction and substantial improvements shall be securely
anchored on piling or columns.
(b)
The pile or column foundation and structure attached thereto
shall be anchored to resist flotation, collapse or lateral movement
due to the effects of wind and water loading values each of which
shall have a 1% chance of being equaled or exceeded in any given year
(one-hundred-year mean recurrence interval).
(c)
Prohibit the use of fill for structural support of buildings
within Coastal A Zones on the community's FIRM.
(3)
Certification. 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 compliance with the provisions of § 20-19B(1) and B(2)(a) and (b).
(4)
Space below the lowest floor.
(a)
Any alteration, repair, reconstruction or improvement to a structure
started after the enactment of this chapter shall not enclose the
space below the lowest floor unless breakaway walls, open-wood latticework
or insect screening are used as provided for in this section.
(b)
Breakaway walls, open-wood latticework or insect screening shall
be allowed below the base flood elevation provided that they are 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. Breakaway walls shall be designed
for a safe loading resistance of not less than 10 and no more than
20 pounds per square foot. Use of breakaway walls which exceed a design
safe loading of 20 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:
[1]
Breakaway wall collapse shall result from a water load less
than that which would occur during the base flood; and
[2]
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 load acting simultaneously
on all building components (structural and nonstructural). 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.
(c)
If breakaway walls are utilized, such enclosed space shall be
used solely for parking of vehicles, building access, or storage and
not for human habitation.
(d)
Prior to construction, plans for any breakaway wall must be
submitted to the Construction Code Official or Building Subcode Official
for approval.
