The following regulations apply within Zone AE and unnumbered
Zone A.
New construction or substantial improvement of any residential
or nonresidential structure shall have the lowest floor elevated one
foot or more above the base flood elevation.
Within Zones AE and in unnumbered A Zones, the following standards
must be met prior to issuing permits for any proposed construction
or development:
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.
B.
Construction materials and methods. All new construction or substantial
improvements shall be constructed with materials and utility equipment
resistant to flood damage and shall use methods and practices that
minimize flooding and flood damage.
C.
Utilities. All new and replacement water supply systems shall be
designed to minimize or eliminate infiltration of floodwater into
the systems. 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. On-site
waste disposal systems shall be located to avoid impairment to them
or contamination from them during flooding. Electrical, heating, ventilation,
plumbing, air conditioning equipment, HVAC ductwork and other service
facilities, or any machinery or utility equipment or connections servicing
a structure shall be elevated to or above the base flood elevation
(BFE) to prevent water from entering or accumulating within the components
during conditions of flooding.
D.
Areas below the lowest floor. For all new construction and substantial
improvements, fully enclosed areas below the lowest floor are usable
solely for the parking of vehicles, building access or storage other
than basements and shall be designed to allow automatic entry and
exit of floodwaters to equalize hydrostatic flood forces on exterior
walls. Electrical, plumbing, HVAC ductwork, machinery and other utility
equipment or connections are prohibited below the base flood elevation.
Designs for meeting this requirement must either be certified by a
professional engineer or architect or must meet or exceed the following
minimum criteria:
(1)
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;
(2)
The
bottom of all openings shall be no higher than one foot above grade;
and
(3)
Openings
may be equipped with screens, louvers, valves or other coverings or
devices. provided that they permit the automatic entry and exit of
floodwaters.
A.
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) will 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.
B.
Within the floodway, as designated on the Floor Insurance Rate Map,
all encroachments, including fill, new construction, substantial improvements
to existing structures and other development, are prohibited unless
the applicant provides a certification with supporting technical data
by a registered professional engineer that demonstrates through hydrologic
and hydraulic analyses performed in accordance with standard engineering
practice that encroachments shall not result in any (0.00) increase
in flood levels or hazards during the occurrence of the one-hundred-year
flood.
C.
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 a 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.
D.
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 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 unrestrained hydraulic connection to the same
waterway or water body. Compensatory storage can be provided off site
if approved by the municipality.
If any portion of a structure lies within the Special Flood
Hazard Area (SFHA), the 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.
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 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.)
New construction, substantial improvements and repair to structures
that have substantial damage cannot be constructed or located entirely
or partially over water unless it is a functionally dependent use
or facility.
Structures which do not meet the requirements of this Article III, may not be rebuilt in kind, but must be made to conform to all the requirements of this regulation.
The following standards apply to all fill activities in the
special flood hazard area:
A.
Fill material, upon which structures will be constructed or placed,
must be compacted to maximum dry density obtainable with the Standard
Proctor Test method according to the ASTM Standard D-698 or an acceptable
equivalent method. Fill soils must be fine-grained soils of low permeability,
such as those classified as CH, CL, SC, or ML according to ASTM Standard
D-2487, Classification of Soils for Engineering Purposes.
B.
Fill slopes shall not be steeper than one foot vertical to two feet
horizontal.
C.
Adequate protection against erosion and scour is provided for fill
slopes. When expected velocities during the occurrence of the base
flood of five feet per second armoring with stone or rock protection
shall be provided. When expected velocities during the base flood
are five feet per second or less, protection shall be provided by
covering them with vegetative cover.
D.
Fill shall be composed of clean granular or earthen material. Fill
material must be homogeneous and isotropic. The soil must be all of
one material, and the engineering properties must be the same in all
directions.
The applicant shall demonstrate that the flood-carrying capacity
of the modified watercourse shall not be diminished. The applicant
shall notify and gain appropriate approval from the Weston Conservation
Commission, adjacent communities, the Connecticut Department of Energy
and Environmental Protection, Inland Water Resources Division, the
Army Corps of Engineers and the Federal Emergency Management Agency
(FEMA) prior to approval of any alteration or relocation of any such
watercourse by the local administrator.
Toxic chemicals and hazardous materials, as defined in any federal
or State of Connecticut statute, rules or regulations which are administered
by the Environmental Protection Agency or Department of Energy and
Environmental Protection shall not be stored in a special flood hazard
area below the base flood elevation.
Aboveground storage tanks (oil, propane, etc.) which are located
outside or inside the structure must either be elevated above the
base flood elevation (BFE) on a concrete pad, or be structurally 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 fill water.
Manufactured homes (as defined in § 212-3) are prohibited from being placed in a special flood hazard area throughout the Town of Weston. 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 in which a manufactured home has incurred substantial damage as a result of a flood. Recreational vehicles in special flood hazard areas shall be on the site for less than 180 consecutive days and be fully licensed and ready for highway use. 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.
