The Floodplain District is established as an overlay district
to all other districts. All development in the district, including
structural and nonstructural activities, whether permitted by right
or by special permit must be in compliance with MGL c. 131, § 40
and with the following:
A. Sections of the Massachusetts State Building Code (780 CMR) which
address floodplain and coastal high hazard areas;
B. Wetlands Protection Regulations, Department of Environmental Protection
(DEP) (currently 310 CMR 10.00);
C. Inland Wetlands Restriction, DEP (currently 310 CMR 13.00);
D. Coastal Wetlands Restriction, DEP (currently 310 CMR 12.00);
E. Minimum Requirements for the Subsurface Disposal of Sanitary Sewage,
DEP (currently 310 CMR 15, Title 5);
F. Any variances from the provisions and requirements of the above referenced
state regulations may only be granted in accordance with the required
variance procedures of these state regulations.
The purpose of the Floodplain District is to protect the public
health, safety, and general welfare, to protect human life and property
from the hazards of periodic flooding and to preserve the natural
flood control characteristics and the flood storage capacity of the
floodplain.
The following requirements apply in the Floodplain District:
A. Within Zone A and AE, where the base flood elevation is not provided
on the FIRM the applicant shall obtain any existing base flood elevation
data and it shall be reviewed by the Building Inspector for its reasonable
utilization toward meeting the elevation of the floodproofing requirements,
as appropriate, of the State Building Code.
B. In Zones A and AE, along watercourses that have not had a regulatory
floodway designated, the best available federal, state, local or other
floodway data shall be used to prohibit encroachments in floodways
which would result in any increase in flood levels within the community
during the occurrence of the base flood discharge.
C. Base flood elevation data is required for subdivision proposals or
other developments greater than 50 lots or five acres, whichever is
the lesser, within unnumbered A Zones.
D. Within Zone A and AE, all new construction and substantial improvements
of residential structures have the lowest floor (including basement)
elevated to or above the base flood level.
E. There shall be no "manufactured homes" within Zone AE.
F. No new construction or substantial improvements, or other development
shall be allowed within Zone AE, unless the applicant demonstrates
to the Building Commissioner that the cumulative effect of the proposed
development, when combined with all other existing and anticipated
development, will not increase the water surface elevation of the
base flood more than one foot at any point within the community.
G. All subdivision proposals must be designed to assure that:
(1) Such proposals minimize flood damage;
(2) All public utilities and facilities are located and constructed to
minimize or eliminate flood damage; and
(3) Adequate drainage is provided to reduce exposure to flood hazards.
H. Within Zone AO on the FIRM, adequate drainage paths must be provided
around structures on slopes, to guide floodwaters around and away
from proposed structures.
I. Located within the Floodplain District are areas designated as coastal
high hazard areas (Zone VE). Since these areas are extremely hazardous
due to high velocity waters from tidal surges and hurricane wave wash,
the following provisions shall apply:
(1) All new construction shall be located landward of the reach of the
mean high tide.
(2) Man-made alteration of sand dunes within flood damage are prohibited.
J. In a riverine situation, the Engineering and Conservation Administrator
shall notify the following of any alteration or relocation of a watercourse:
(2) Bordering states (optional).
(3) NFIP State Coordinator, Massachusetts Department of Conservation
and Recreation, 251 Causeway Street, Suite 600-700, Boston, MA 02114-2104.
(4) NFIP Program Specialist, Federal Emergency Management Agency, Region
I, 99 High Street, 6th Floor, Boston, MA 02110.
The following definitions shall apply to the terms used within
this Floodplain District Bylaw.
AREA OF SPECIAL FLOOD HAZARD
The land in the floodplain within a community subject to
a one percent or greater chance of flooding in any given year. The
area may be designated as Zone A, AO, AH, A1-30, AE, A99, V1-30, VE,
or V.
BASE FLOOD
The flood having a one percent chance of being equaled or
exceeded in any given year.
COASTAL HIGH HAZARD AREA
An area of special flood hazard extending from offshore to
the inland limit of a primary frontal dune along an open coast and
any other area subject to high velocity wave action from storms or
seismic sources. The area is designated on a FIRM as Zone VE.
DEVELOPMENT
Any man-made change to improved or unimproved real estate,
including but not limited to building or other structures, mining,
dredging, filling, grading, paving, excavation or drilling operations.
FEDERAL EMERGENCY MANAGEMENT AGENCY (FEMA)
Administers the National Flood Insurance Program. FEMA provides
a nationwide flood hazard area mapping study program for communities
as well as regulatory standards for development in the flood hazard
areas.
FLOOD INSURANCE RATE MAP (FIRM)
An official map of a community on which FEMA has delineated
both the areas of special flood hazard and the risk premium zones
applicable to the community.
FLOOD INSURANCE STUDY
An examination, evaluation, and determination of flood hazards,
and, if appropriate, corresponding water surface elevations, or an
examination, evaluation and determination of flood-related erosion
hazards.
FLOODWAY
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.
LOWEST FLOOR
The lowest floor of the lowest enclosed area (including basement
or cellar). An unfinished or flood resistant enclosure, usable solely
for parking of vehicles, building access or storage in an area other
than a basement area is not considered a building's lowest floor,
provided that such enclosure is not built so as to render the structure
in violation of the applicable nonelevation design requirements of
NFIP Regulations 60.3.
MANUFACTURED HOME
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 connected to the required utilities. For
floodplain management purposes the term "manufactured home" also includes
park trailers, travel trailers, and other similar vehicles placed
on a site for greater than 180 consecutive days. For insurance purposes,
the term "manufactured home" does not include park trailers, travel
trailers, and other similar vehicles.
NEW CONSTRUCTION
For floodplain management purposes, structures for which
the "start of construction" commenced on or after the effective date
of a floodplain management regulation adopted by a community. For
the purpose of determining insurance rates, new construction means
structures for which the "start of construction" commenced on or after
the effective date of an initial FIRM or after December 31, 1974,
whichever is later.
SPECIAL FLOOD HAZARD AREA
An area having special flood and/or flood-related erosion
hazards, and shown on a FIRM as Zone A, AO, A1-30, AE, A99, AH, V,
V1-30, VE.
STRUCTURE
For floodplain management purposes, a walled and roofed building,
including a gas or liquid storage tank, that is principally aboveground,
as well as a manufactured home. Structure, for insurance coverage
purposes, means a walled and roofed building, other than a gas or
liquid storage tank, that is principally above ground and affixed
to a permanent site, as well as a manufactured home on foundation.
For the latter purpose, the term includes a building while in the
course of construction, alteration, or repair, but does not include
building materials or supplies intended for use in such construction,
alteration, or repair, unless such materials or supplies are within
an enclosed building on the premises.
SUBSTANTIAL DAMAGE
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.
SUBSTANTIAL IMPROVEMENT
Any repair, reconstruction, or improvement of a structure,
the cost of which equals or exceeds 50% of the market value of the
structure either (a) before the improvement or repair is started,
or (b) if the structure has been damaged and is being restored, before
the damage occurred. For the purposes of this definition, "substantial
improvement" is considered to occur when the first alteration of any
wall, ceiling, floor, or other structural part of the building commences,
whether or not that alteration affects the external dimensions of
the structure.
ZONE A
The one-hundred-year floodplain area where the base flood
elevation (BFE) has not been determined. To determine the BFE, use
the best available federal, state, local, or other data.
ZONE AO
The one-hundred-year floodplain with flood depths of one
to three feet, where a clearly defined channel does not exist, where
the path of flooding is unpredictable, and where velocity flow may
be evident. Such flooding is characterized by ponding or sheet flow.
ZONE VE (for new and revised maps)
A special flood hazard area along a coast subject to inundation
by the one-hundred-year flood with additional hazards due to velocity
(wave action). Base flood elevations have been determined.
ZONE X
Areas identified in the community Flood Insurance Study as
areas of moderate or minimal flood hazard. Zone X replaces Zones B
and C on new and revised maps.