Article Index

SECTION 6 - DEVELOPMENT STANDARDS
All developments in areas of special flood hazard shall meet the following applicable standards:
A. All Development - All development shall:
1. be designed or modified and adequately anchored to prevent flotation (excluding
piers and docks), collapse or lateral movement of the development resulting from
hydrodynamic and hydrostatic loads, including the effects of buoyancy;
2. use construction materials that are resistant to flood damage;
3. use construction methods and practices that will minimize flood damage; and,
4. use 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 flooding conditions.
B. Water Supply - All new and replacement water supply systems shall be designed to
minimize or eliminate infiltration of flood waters into the systems.
C. Sanitary Sewage Systems - All new and replacement sanitary sewage systems shall be
designed and located to minimize or eliminate infiltration of flood waters into the system
and discharges from the system into flood waters.
D. On Site Waste Disposal Systems - On site waste disposal systems shall be located and
constructed to avoid impairment to them or contamination from them during floods.
E. Watercourse Carrying Capacity - All development associated with altered or relocated
portions of a watercourse shall be constructed and maintained in such a manner that no
reduction occurs in the flood carrying capacity of the watercourse.
F. Residential - New construction or substantial improvement of any residential structure
located within Zone A shall have the lowest floor (including basement) elevated to at least
one foot above the base flood elevation utilizing information obtained pursuant to Section
3.G.1; Section 5.B; or Section 9.D.
G. Non Residential - New construction or substantial improvement of any non-residential
structure located within Zone A shall have the lowest floor (including basement) elevated
to at least one foot above the base flood elevation utilizing information obtained pursuant
to Section 3.G.1.; Section 5.B; or Section 9.D., or together with attendant utility and
sanitary facilities shall:
1. be floodproofed to at least one foot above the base flood elevation utilizing
information obtained pursuant to Section 3.G.1.; Section 5.B; or Section 9.D., so
that below that elevation the structure is watertight with walls substantially
impermeable to the passage of water;
2. have structural components capable of resisting hydrostatic and hydrodynamic
loads and the effects of buoyancy; and,
3. be certified by a registered professional engineer or architect that the
floodproofing design and methods of construction are in accordance with
accepted standards of practice for meeting the provisions of this section. Such
certification shall be provided with the application for a Flood Hazard
Development Permit, as required by Section 3.J. and shall include a record of the
elevation above mean sea level to which the structure is floodproofed.
H. Manufactured Homes - New or substantially improved manufactured homes located
within Zone A shall:
1. be elevated such that the lowest floor (including basement) of the manufactured
home is at least one foot above the base flood elevation utilizing information
obtained pursuant to Section 3.G.1.; Section 5.B; or Section 9.D.;
2. be on a permanent foundation, which may be poured masonry slab or foundation
walls, with hydraulic openings, or may be reinforced piers or block supports, any
of which support the manufactured home so that no weight is supported by its
wheels and axles; and,
3. be securely anchored to an adequately anchored foundation system to resist
flotation, collapse, or lateral movement. Methods of anchoring may include, but
are not limited to:
a. over-the-top ties anchored to the ground at the four corners of the
manufactured home, plus two additional ties per side at intermediate
points (manufactured homes less than 50 feet long require one additional
tie per side); or by,
b. frame ties at each corner of the home, plus five additional ties along
each side at intermediate points (manufactured homes less than 50 feet
long require four additional ties per side).
c. all components of the anchoring system described in Section 6.H.3.a.&
b. shall be capable of carrying a force of 4800 pounds.
I. Accessory Structures - Accessory Structures, as defined in Section 14, located within
Zone A, shall be exempt from the elevation criteria required in Section 6.F. & G. above, if
all other requirements of Section 6 and all the following requirements are met. Accessory
Structures shall:
1. be 500 square feet or less and have a value less than $3000;
2. have unfinished interiors and not be used for human habitation;
3. have hydraulic openings, as specified in Section 6.K.2., in at least two different
walls of the accessory structure;
4. be located outside the floodway;
5. when possible be constructed and placed on the building site so as to offer the
minimum resistance to the flow of floodwaters and be placed further from the
source of flooding than is the primary structure; and,
6. have only ground fault interrupt electrical outlets. The electric service disconnect
shall be located above the base flood elevation and when possible outside the
Special Flood Hazard Area.
J. Floodways - Encroachments, including fill, new construction, substantial improvement,
and other development shall not be permitted in a floodway which, in Zone A riverine
areas, is the channel of the river or other water course and the adjacent land areas to a
distance of one-half the width of the floodplain as measured from the normal high water
mark to the upland limit of the floodplain, unless a technical evaluation certified by a
registered professional engineer is provided demonstrating that the cumulative effect of
the proposed development, when combined with all other existing development and
anticipated development:
1. will not increase the water surface elevation of the base flood more than one foot
at any point within the community; and,
2. is consistent with the technical criteria contained in Chapter 5 entitled "Hydraulic
Analyses," Flood Insurance Study - Guidelines and Specifications for Study
Contractors, (FEMA 37/ January 1995, as amended).
K. Enclosed Areas Below the Lowest Floor - New construction or substantial
improvement of any structure in Zone A that meets the development standards of Section
6, including the elevation requirements of Section 6, paragraphs F, G, or H and is
elevated on posts, columns, piers, piles, "stilts," or crawlspaces may be enclosed below
the base flood elevation requirements provided all the following criteria are met or
exceeded:
1. Enclosed areas are not "basements" as defined in Section 14;
2. Enclosed areas shall be designed to automatically equalize hydrostatic flood
forces on exterior walls by allowing for the entry and exit of flood water. Designs
for meeting this requirement must either:
a. be engineered and certified by a registered professional engineer or
architect; or,
b. meet or exceed the following minimum criteria:
(1) a minimum of two openings having a total net area of not less
than one square inch for every square foot of the enclosed area;
(2) the bottom of all openings shall be below the base flood
elevation and no higher than one foot above the lowest grade;
and,
(3) openings may be equipped with screens, louvers, valves, or
other coverings or devices provided that they permit the entry
and exit of flood waters automatically without any external
influence or control such as human intervention, including the
use of electrical and other non-automatic mechanical means;
3. The enclosed area shall not be used for human habitation; and,
4. The enclosed areas are usable solely for building access, parking of vehicles, or
storage.
L. Bridges - New construction or substantial improvement of any bridge in Zone A shall be
designed such that:
1. when possible, the lowest horizontal member (excluding the pilings, or columns)
is elevated to at least one foot above the base flood elevation utilizing information
obtained pursuant to Section 3.G.1.; Section 6.J.; and Section 9.D.
2. a registered professional engineer shall certify that:
a. the structural design and methods of construction shall meet the
elevation requirements of this section and the floodway standards of
Section 6.J.; and
b. the foundation and superstructure attached thereto are designed to resist
flotation, collapse and lateral movement due to the effects of wind and
water loads acting simultaneously on all structural components. Water
loading values used shall be those associated with the base flood.
M. Containment Walls - New construction or substantial improvement of any containment
wall located within Zone A shall:
1. have the containment wall elevated to at least one foot above the base flood
elevation utilizing information obtained pursuant to Section 3.G.1.; Section 5 .B.;
or Section 9.D.
2. have structural components capable of resisting hydrostatic and hydrodynamic
loads and the effects of buoyancy; and
3. be certified by a registered professional engineer or architect that the design and
methods of construction are in accordance with accepted standards of practice
for meeting the provisions of this section. Such certification shall be provided with
the application for a Flood Hazard Development Permit, as required by Section
3.J.
N. Wharves, Piers and Docks - New construction or substantial improvement of wharves,
piers, and docks are permitted in Zone A in and over water and seaward of the mean
high tide if the following requirements are met:
1. wharves, piers, and docks shall comply with all applicable local, state, and
federal regulations; and
2. for commercial wharves, piers, and docks, a registered professional engineer
shall develop or review the structural design, specifications, and plans for the
construction.
O. Coastal Floodplains -
1. All new construction located within Zone A shall be located landward of the reach
of mean high tide except as provided in Section 6.O.2.
2. Conditional Use - Lobster sheds and fishing sheds may be located seaward of
mean high tide and shall be exempt from the elevation requirement in Section
6.G. only if permitted as a Conditional Use following review and approval by the
Planning Board, as provided in Section 7, and if all the following requirements
and those of Section 6.A., 6.J., and 6.K. are met:
a. The conditional use shall be limited to low value structures such as metal
or wood sheds and shall not exceed more than one story.
b. The structure shall be securely anchored to the wharf or pier to resist
flotation, collapse, and lateral movement due to the effect of wind and
water loads acting simultaneously on all building components.
c. The structure will not adversely increase wave or debris impact forces
affecting nearby buildings.
d. The structure shall have unfinished interiors and shall not be used for
human habitation.
e. Any mechanical, utility equipment and fuel storage tanks must be
anchored and either elevated or floodproofed to one foot above the base
flood elevation.
f. All electrical outlets shall be ground fault interrupt type. The electrical
service disconnect shall be located on shore above the base flood
elevation and when possible outside the Special Flood Hazard Area.