In all areas of special flood hazard, the following provisions
are required:
A.
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.
B.
New construction and substantial improvements shall be constructed
with materials resistant to flood damage.
C.
New construction or substantial improvements shall be constructed
by methods and practices that minimize flood damage.
D.
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.
E.
New and replacement water supply systems shall be designed to minimize
or eliminate infiltration of floodwaters into the system.
F.
New and replacement sanitary sewage systems shall be designed to
minimize or eliminate infiltration of floodwaters into the systems
and discharges from the system into floodwaters.
G.
On-site waste disposal systems shall be located and constructed to
avoid impairment to them or contamination from them during flooding.
H.
Manufactured homes.
(1)
All manufactured homes (including mobile homes and recreational vehicles
placed on a site for 180 consecutive days or longer) to be placed
or substantially improved shall be elevated so that the lowest floor
is above the base flood elevation. This includes manufactured homes
located outside 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 on a site in an existing park which a
manufactured home has incurred substantial damage as a result of a
flood.
(2)
They 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)
They shall be installed using methods and practices which minimize
flood damage.
(4)
Recreational vehicles placed on sites within areas of special flood hazard shall either be on the site for fewer than 180 consecutive days and be fully licensed and ready for highway use, or meet the elevation and anchoring requirements for a manufactured home listed in this Subsection H. 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.
I.
In any portion of a watercourse which is altered or relocated, the
flood-carrying capacity shall be maintained.
J.
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.
K.
Equal conveyance. 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 as to cause an increase in flood
stage or flood velocity.
L.
Compensatory storage. 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.
M.
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.
N.
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, sun rooms, 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.
O.
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, sun rooms, 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.)
P.
No structures 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.
A.
The Conservation Director shall obtain, review and reasonably utilize any base flood elevation and floodway data available from a federal, state, or other source as criteria for requiring that new construction, substantial improvements, or other development in Zone A on the community's FIRM meets the standards in § 136-18A, 136-18B, § 136-18C, and Article VI.
B.
When utilizing data other than that provided by the Federal Emergency
Management Agency, the Newtown Conservation Commission shall 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.
C.
In A Zones where base flood elevations have been determined, but
before a floodway is designated, the Conservation Director shall require
that no new construction, substantial improvement or other development
(including fill) be permitted which would 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.
A.
In all areas of special flood hazard A and AE, the following provisions
are required:
(1)
Residential construction. New construction or substantial improvement
of any residential structure shall have the lowest floor, including
basement, elevated at least to four feet above the base flood elevation.
(2)
Nonresidential construction.
(a)
New construction or substantial improvement of any commercial,
industrial, or nonresidential structure located in Zone A or AE shall
have the lowest floor, including basement, elevated at least to 10
feet above the level of the base flood elevation; or
(b)
Nonresidential structures located in all A or AE Zones 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 required elevation are watertight with walls substantially impermeable to the passage of water, and structural components having the capability of resisting hydrostatic and hydrodynamic loads and the effect of buoyancy are used. A registered professional engineer or architect shall review and develop 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. Such certification shall be provided to the official as set forth in § 136-14A(6), and must be supported by hydrologic and hydraulic analysis performed in accordance with standard engineering practices.
B.
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 be certified by
a professional engineer or architect and meet the following minimum
criteria:
(a)
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; and
(c)
Openings may be equipped with screens, louvers, valves or other
coverings or devices, provided 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).
C.
Floodways. Located within areas of special flood hazard established in § 136-7 are areas designated as floodways on the community's Flood Insurance Rate Map. Since the floodway is an extremely hazardous area due to the velocity of floodwaters which carry debris, potential projectiles and has erosion potential, the following provisions shall apply: prohibit encroachments, including fill, new construction, substantial improvements and other developments, 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 increase in flood levels during occurrence of the base flood discharge.
