In all areas of special flood hazards the following provisions
are required for all new construction and substantial improvements:
(1)
All new
construction or substantial improvements shall 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;
(2)
All new
construction or substantial improvements shall be constructed by methods
and practices that minimize flood damage;
(3)
All new
construction or substantial improvements shall be constructed with
materials resistant to flood damage;
(4)
All new
construction or substantial improvements shall 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;
(5)
All new
and replacement water supply systems shall be designed to minimize
or eliminate infiltration of flood waters into the system;
(6)
New and
replacement sanitary sewage systems shall be designed to minimize
or eliminate infiltration of flood waters into the system and discharge
from the systems into flood waters; and
(7)
On-site
waste disposal systems shall be located to avoid impairment to them
or contamination from them during flooding.
(Ordinance 618, art. 5, sec. A,
adopted 7/22/97)
In all areas of special flood hazards where base flood elevation data has been provided as set forth in (i) section 7-27, (ii) subsection 7-57(8), or (iii) subsection 7-83(3), the following provisions are required:
(1)
Residential
construction–
New construction and substantial
improvement of any residential structure shall have the lowest floor
(including basement), elevated to or above the base flood elevation
plus one foot. A registered professional engineer, architect, or land
surveyor shall submit a certification to the floodplain administrator
that the standard of this subsection as proposed in subsection 7-58(1)a.,
is satisfied.
(2)
Nonresidential
construction–
New construction and substantial
improvements of any commercial, industrial or other nonresidential
structure shall either have the lowest floor (including basement)
elevated to or above the base flood level plus one foot or together
with attendant utility and sanitary facilities, be designed so that
below the base flood level plus one foot 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. 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 as outlined in this subsection. A record
of such certification which includes the specific elevation (in relation
to mean sea level) to which such structures are floodproofed shall
be maintained by the floodplain administrator.
(3)
Enclosures–
New construction and substantial improvements, with 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.
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.
b.
The bottom
of all openings shall be no higher than one foot above grade.
c.
Openings
may be equipped with screens, louvers, valves, or other coverings
or devices provided that they permit the automatic entry and exit
of floodwaters.
(4)
Manufactured
homes.
a.
Require
that all manufactured homes to be placed within zone A on a community’s
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. Methods of anchoring may include, but are not
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 forces.
b.
Require
that manufactured homes that are placed or substantially improved
within zones A1-30, AH, and AE on the community’s FIRM on sites
(i) outside of a manufactured home park or subdivision, (ii) in a
new manufactured home park or subdivision, (iii) in an expansion to
an existing manufactured home park or subdivision, or (iv) 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
plus one foot and be securely anchored to an adequately anchored foundation
system to resist flotation, collapse, and lateral movement.
c.
Require
that manufactured homes be placed or substantially improved on sites
in an existing manufactured home park or subdivision with zones A1-30,
AH and AE on the community’s FIRM that are not subject to the
provisions of subsection (4) of this section be elevated so that either:
1.
The
lowest floor of the manufactured home is at or above the base flood
elevation plus one foot; or
2.
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.
(5)
Recreational
vehicles–
Require that recreational vehicles placed on sites within zones A1-30, AH, and AE on the community’s FIRM either (i) be on the site for fewer than 180 consecutive days, (ii) be fully licensed and ready for highway use, or (iii) meet the permit requirements of subsection 7-58(1), and the elevation and anchoring requirements for “manufactured homes” in subsection (4) of this section. 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.
(6)
Floodplain
compensation–
Whenever any portion of a floodplain
is authorized for use, the space occupied by the authorized fill or
structure below the base flood elevation shall be compensated for
and balanced by a hydraulically equivalent volume of excavation taken
from below the base flood elevation. All such excavations shall be
constructed to drain freely to the watercourse.
(Ordinance 618, art. 5, sec. B,
adopted 7/22/97; Ordinance
708, secs. 2–6, adopted 6/23/06)
(c)
Base flood elevation data shall be generated for subdivision proposals and other proposed development including the placement of manufactured home parks and subdivisions which is greater than 50 lots or five acres, whichever is lesser, if not otherwise provided pursuant to section 7-27 or subsection 7-57(8) of this chapter.
(d)
All subdivision
proposals including the placement of manufactured home parks and subdivisions
shall have adequate drainage provided to reduce exposure to flood
hazards.
(e)
All subdivision
proposals including the placement of manufactured home parks and subdivisions
shall have public utilities and facilities such as sewer, gas, electrical
and water systems located and constructed to minimize or eliminate
flood damage.
(Ordinance 618, art. 4, sec. C,
adopted 7/22/97)
Located within the areas of special flood hazard established in section 7-27 areas designated as shallow flooding. These areas have special flood hazards associated with base flood depths of one to three feet where a clearly defined channel does not exist and where the path of flooding is unpredictable and where velocity flow may be evident. Such flooding is characterized by ponding or sheet flow; therefore, the following provisions apply:
(1)
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 community’s FIRM (at least two feet if no depth number
is specified).
(2)
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
community’s FIRM (at least two feet if no depth number is specified),
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 of effects of buoyancy.
(3)
A registered
professional engineer or architect shall submit a certification to
the floodplain administrator that the standards of this section, as
proposed in subsection 7-58(1)a., are satisfied.
(4)
Require
within zones AH or AO adequate drainage paths around structures on
slopes, to guide flood waters around and away from proposed structures.
(Ordinance 618, art. 4, sec. D,
adopted 7/22/97)
Floodways located within areas of special flood hazard established in section 7-27 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of flood waters which carry debris, potential projectiles and erosion potential, the following provisions shall apply:
(1)
Encroachments
are prohibited, 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 community during the occurrence of the base flood discharge.
(2)
If subsection 7-85(1) above is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of article IV.
(3)
Under the provisions of 44 CFR Chapter 1, Section 65.12, of the National Flood Insurance Regulations, a community may permit encroachments within the adopted regulatory floodway that would result in an increase in base flood elevations, provided that the community first applies for a conditional FIRM and floodway revision through FEMA.
(Ordinance 618, art. 4, sec. E,
adopted 7/22/97)
No structure or land shall hereafter be constructed, located,
extended, converted, or altered 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 conditions) shall constitute a misdemeanor. Any person
who violates this chapter or fails to comply with any of its requirements
shall upon conviction thereof be fined not more than $1,000.00, for
each violation, and in addition shall pay all costs and expenses involved
in the case. Nothing herein contained shall prevent the city from
taking such other lawful action as is necessary to prevent or remedy
any violation.
(Ordinance 618, art. 4, sec. F,
adopted 7/22/97)
