In all areas of special flood hazard, the following
standards are required:
A.
Anchoring. All new construction and substantial improvements
shall be anchored to prevent flotation, collapse or lateral movement
of the structure resulting from hydrodynamic and hydrostatic loads,
including the effects of buoyancy.
[Amended 10-19-2010 by Ord. No. 241]
B.
Construction materials and methods.
(1)
All new construction and substantial improvements
shall be constructed with materials and utility equipment resistant
to flood damage.
(2)
All new construction and substantial improvements
shall be constructed using methods and practices that minimize flood
damage.
(3)
Electrical, heating, ventilation, plumbing, air-conditioning
equipment and other service facilities shall be designed and/or located
so as to prevent water from entering or accumulating within the components
during conditions of flooding.
C.
Utilities.
(1)
All new and replacement water supply systems shall
be designed to minimize or eliminate infiltration of floodwater into
the system.
(2)
New and replacement sanitary sewer 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.
D.
All manufactured homes to be placed within Zone A
on a community's 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 to be limited to, use of over-the-top frame ties to ground
anchors.
E.
Undesignated floodways.
(1)
In A Zones where base flood elevations have been determined,
but before a floodway is designated, no new construction, substantial
improvements or other development, including fill, shall be permitted
which will increase base flood elevations more than one foot at any
point along the watercourse when all anticipated development is considered
cumulatively with the proposed development.
(2)
Should data be requested and/or provided, the town
shall adopt a regulatory floodway based on the principle that the
floodway must be able to convey the waters of the base flood without
increasing the water surface elevation more than one foot at any point
along the watercourse.
F.
Aboveground
storage tanks. Aboveground storage tanks (oil, propane, etc.) which
are located outside or inside of the structure must either be elevated
above the base flood elevation (BFE) on a concrete pad or be securely
anchored with tie-down straps to prevent flotation or lateral movement,
have the top of the fill pipe extended above the BFE, and have a screw
fill cap that does not allow for the infiltration of floodwater.
[Added 10-19-2010 by Ord. No. 241]
G.
Portion
of structure in flood zone. If any portion of a structure lies within
the special flood hazard area (SFHA), the entire structure is considered
to be in the SFHA. The entire structure must meet the construction
requirements of the flood zone. The structure includes any attached
additions, garages, decks, sunrooms, or any other structure attached
to the main structure. Decks or porches that extend into a more restrictive
flood zone will require the entire structure to meet the standards
of the more restrictive zone.
[Added 10-19-2010 by Ord. No. 241]
H.
Structures
in two flood zones. If a structure lies within two or more flood zones,
the construction standards of the most restrictive zone apply to the
entire structure (i.e., V zone is more restrictive than A zone; structure
must be built to the highest BFE). The structure includes any attached
additions, garages, decks, sunrooms, or any other structure attached
to the main structure. Decks or porches that extend into a more restrictive
zone will require the entire structure to meet the requirements of
the more restrictive zone.
[Added 10-19-2010 by Ord. No. 241]
I.
No structure
entirely or partially over water. New construction, substantial improvements
and repair to structures that have sustained substantial damage cannot
be constructed or located entirely or partially over water unless
it is a functionally dependent use or facility.
[Added 10-19-2010 by Ord. No. 241]
In all areas of special flood hazard where base flood elevation data has been provided as set forth in § 148-3 or in § 148-11B, the following standards are required:
A.
Residential construction. New construction and substantial
improvement of any residential structure shall have the lowest floor,
including basement, elevated at least one foot above the base flood
elevation.
B.
Nonresidential construction.
(1)
New construction and substantial improvement of any
commercial, industrial or other nonresidential structure shall either
have the lowest floor, including basement, elevated to one foot above
the level of the base flood elevation; or
(2)
Nonresidential structures may be floodproofed in lieu
of being elevated, provided that, together with all attendant utilities
and sanitary facilities, the areas of the structure below the elevation
of one foot above the level of the base flood elevation are watertight
with walls substantially impermeable to the passage of water, and
use structural components having the capability of resisting hydrostatic
and hydrodynamic loads and the effect of buoyancy. A registered professional
engineer or architect shall provide structural design, specifications
and plans for the construction, and shall certify that the design
and methods of construction are in accordance with acceptable standards
of practice for meeting the provisions of this subsection.
C.
Elevated buildings. New construction or substantial
improvements of elevated buildings that include fully enclosed areas
formed by foundation and other exterior walls below the base flood
elevation shall be designed to preclude finished living space and
designed to allow for the entry and exit of floodwaters to automatically
equalize hydrostatic flood forces on exterior walls.
(1)
Designs for complying with this requirement must either
be certified by a professional engineer or architect or be certified
that:
(a)
They provide 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.
(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 flow of floodwaters in both directions.
(2)
Electrical, plumbing and other utility connections
are prohibited below the base flood elevation.
(3)
Access to the enclosed area shall be the minimum necessary
to allow for parking of vehicles (garage door) or limited storage
of maintenance equipment used in connection with the premises (standard
exterior door) or entry to the living area (stairway or elevator).
D.
Manufactured homes.
(1)
All manufactured homes to be placed or substantially
improved shall be elevated so that the lowest floor is above the base
flood elevation. This includes manufactured homes outside of a manufactured
home park or subdivision, in a new manufactured home park or subdivision,
in an existing 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 a flood.
[Amended 10-19-2010 by Ord. No. 241]
(2)
Manufactured homes shall be placed on a permanent
foundation which itself is securely anchored and to which the structure
is securely anchored so that it will resist flotation, lateral movement
and hydrostatic and hydrodynamic pressures. Anchoring may include,
but not be limited to, the use of over-the-top or frame ties to ground
anchors.
(3)
Manufactured homes shall be installed using methods
and practices which minimize flood damage.
(4)
In any portion of a watercourse which is altered or
relocated, the flood-carrying capacity shall be maintained.
(5)
A structure already in compliance with the provisions
of this chapter shall not be made noncompliant by any alteration,
repair, reconstruction or improvement to the structure.
E.
Recreational vehicles. Recreational vehicles placed on sites within all areas of special flood hazard shall either a) be on the site for fewer than 180 consecutive dates and be fully licensed and ready for highway use, or b) meet all of the general standards of § 148-14 and the elevation and anchoring requirement of § 148-15D. 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.
[Added 10-19-2010 by Ord. No. 241]
Located within areas of special flood hazard established in § 148-3 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 shall apply:
A.
Encroachments, including fill, new construction, substantial
improvements, repairs to substantially damaged structures and other
developments shall be prohibited unless certification, with supporting
technical data, by a registered professional engineer is provided
demonstrating, through hydrologic and hydraulic analyses performed
in accordance with standard engineering practice, that encroachments
shall not result in any (0.00 feet) increase in flood levels during
the occurrence of the base flood discharge. Fences in the floodway
must be aligned with the flow and be of an open design.
[Amended 10-19-2010 by Ord. No. 241]
[Added 10-19-2010 by Ord. No. 241]
The water holding capacity of the floodplain, except those areas
which are tidally influenced, shall not be reduced. Any reduction
caused by filling, new construction or substantial improvements involving
an increase in footprint to the structure shall be compensated for
by deepening and/or widening of the floodplain, storage shall be provided
on site, unless easements have been gained from adjacent property
owners; it shall be provided within the same hydraulic reach and a
volume not previously used for flood storage; it shall be hydraulically
comparable and incrementally equal to the theoretical volume of floodwater
at each elevation, up to and including the one-hundred-year flood
elevation, which would be displaced by the proposed project. Such
compensatory volume shall have an unrestricted hydraulic connection
to the same waterway or water body. Compensatory storage can be provided
off site if approved by the municipality.
[Added 10-19-2010 by Ord. No. 241]
Within the floodplain, except those areas which are tidally
influenced, as designated on the Flood Insurance Rate Map (FIRM) for
the community, encroachments resulting from filling, new construction
or substantial improvements involving an increase in footprint of
the structure are prohibited unless the applicant provides certification
by a registered professional engineer demonstrating, with supporting
hydrologic and hydraulic analyses performed in accordance with standard
engineering practice, that such encroachments shall not result in
any (0.00 feet) increase in flood levels (base flood elevation). Work
within the floodplain and the land adjacent to the floodplain, including
work to provide compensatory storage, shall not be constructed in
such a way so as to cause an increase in flood stage or flood velocity.
