The following standards apply to new development, including new and substantially improved structures, in the areas of special flood hazard shown on the Flood Insurance Rate Map designated in § 182-3.2:
A.
Subdivision proposals. The following standards apply to all new subdivision
proposals and other proposed development in areas of special flood
hazard (including proposals for manufactured home and recreational
vehicle parks and subdivisions):
(1)
Proposals shall be consistent with the need to minimize flood
damage; and
(2)
Public utilities and facilities, such as sewer, gas, electrical
and water systems, shall be located and constructed so as to minimize
flood damage; and
(3)
Adequate drainage shall be provided to reduce exposure to flood
damage.
B.
Encroachments.
(1)
Within Zones A1-A30 and AE, on streams without a regulatory
floodway, no new construction, substantial improvements or other development
(including fill) shall be permitted unless:
(a)
The applicant demonstrates 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 location; or
(b)
The Town of Lancaster agrees to apply to the Federal Emergency
Management Agency (FEMA) for a conditional FIRM revision, FEMA approval
is received, and the applicant provides all necessary data, analyses
and mapping and reimburses the Town of Lancaster for all fees and
other costs in relation to the application. The applicant must also
provide all data, analyses and mapping and reimburse the Town of Lancaster
for all costs related to the final map revision.
(2)
On streams with a regulatory floodway, as shown on the Flood Boundary and Floodway Map or the Flood Insurance Rate Map adopted in § 182-3.2, no new construction, substantial improvements or other development in the floodway (including fill) shall be permitted unless:
(a)
A technical evaluation by a licensed professional engineer demonstrates
through hydrologic and hydraulic analyses performed in accordance
with standard engineering practice that such an encroachment shall
not result in any increase in flood levels during occurrence of the
base flood; or
(b)
The Town of Lancaster agrees to apply to the Federal Emergency
Management Agency (FEMA) for a conditional FIRM and floodway revision,
FEMA approval is received and the applicant provides all necessary
data, analyses and mapping and reimburses the Town of Lancaster for
all fees and other costs in relation to the application. The applicant
must also provide all data, analyses and mapping and reimburse the
Town of Lancaster for all costs related to the final map revision.
(3)
In Zones A1-A30, AE and AH, and also Zone A if base flood elevation
data are available, if any development is found to increase or decrease
base flood elevations, the Town of Lancaster shall, as soon as practicable,
but not later than six months after the date such information becomes
available, notify FEMA and the New York State Department of Environmental
Conservation of the changes by submitting technical or scientific
data in accordance with standard engineering practice.
(4)
Whenever any portion of a floodplain is authorized for development,
the volume of space occupied by the authorized fill or structure below
the base flood elevation shall be compensated for and balanced by
a hydraulically equivalent volume of excavation taken from below the
base flood elevation at or adjacent to the development site. All such
excavations shall be constructed to drain freely to the watercourse.
No area below the waterline of a pond or other body of water can be
credited as a compensating excavation.
The following standards apply to new development, including new and substantially improved structures, in the areas of special flood hazard shown on the Flood Insurance Rate Map designated in § 182-3.2.
A.
Anchoring. New structures and substantial improvement to structures
in areas of special flood hazard shall be anchored to prevent flotation,
collapse or lateral movement during the base flood. This requirement
is in addition to applicable state and local anchoring requirements
for resisting wind forces.
B.
Construction materials and methods.
(1)
New construction and substantial improvements to structures
shall be constructed with materials and utility equipment resistant
to flood damage.
(2)
New construction and substantial improvements to structures
shall be constructed using methods and practices that minimize flood
damage.
(3)
Enclosed areas.
(a)
For enclosed areas below the lowest floor of a structure within
Zone A1-A30, AE, AO or A, new and substantially improved structures
shall have fully enclosed areas below the lowest floor that are usable
solely for parking of vehicles, building access or storage in an area
other than a basement and which are subject to flooding, designed
to automatically equalize hydrostatic flood forces on exterior walls
by allowing for the entry and exit of floodwaters. Designs for meeting
this requirement must either be certified by a licensed professional
engineer or architect or meet or exceed the following minimum criteria:
[1]
A minimum of two openings of each enclosed area having a total
net area of not less than one square inch for every square foot of
enclosed area subject to flooding; and
[2]
The bottom of all such openings no higher than one foot above
the lowest adjacent finished grade; and
[3]
Openings shall not be less than three inches in any direction.
(b)
Openings may be equipped with louvers, valves, screens or other
coverings or devices, provided that they permit the automatic entry
and exit of floodwaters. Enclosed areas subgrade on all sides are
considered basements and are not permitted.
C.
Utilities.
(1)
New and replacement electrical equipment, heating, ventilating,
air conditioning, plumbing connections, and other service equipment
shall be located at least two feet above the base flood elevation,
or at least three feet above the highest adjacent grade in a Zone
A without an available base flood elevation where permitted or be
designed to prevent water from entering and accumulating within the
components during a flood and to resist hydrostatic and hydrodynamic
loads and stresses. Electrical wiring and outlets, switches, junction
boxes and panels shall be elevated or designed to prevent water from
entering and accumulating within the components unless they conform
to the appropriate provisions of the electrical part of the Building
Code of New York State or the Residential Code of New York State for
location of such items in wet locations.
(2)
New and replacement water supply systems shall be designed to
minimize or eliminate infiltration of floodwaters into the system.
(3)
New and replacement sanitary sewage systems shall be designed
to minimize or eliminate infiltration of floodwaters. Sanitary sewer
and storm drainage systems for buildings that have openings below
the base flood elevation shall be provided with automatic backflow
valves or other automatic backflow devices that are installed in each
discharge line passing through a building's exterior wall.
(4)
On-site waste disposal systems shall be located to avoid impairment
to them or contamination from them during flooding.
Elevation. The following standards, in addition to the requirements in § 182-5.1A, Subdivision proposals, and § 182-5.1B, Encroachments, and § 182-5.2, Standards for all structures, apply to new and substantially improved residential structures located in areas of special flood hazard, as indicated:
A.
Within special flood hazard areas, new construction and substantial
improvements shall have the lowest floor (including basement) elevated
to or above two feet above the base flood elevation.
B.
Within Zone A, if the base flood elevation is not specified, a base
flood elevation shall be determined by either of the following:
(1)
Obtain and reasonably use data available from a federal, state
or other source plus two feet of freeboard; or
(2)
Determine the base flood elevation in accordance with accepted
hydrologic and hydraulic engineering practices, plus freeboard. Determinations
shall be undertaken by a registered design professional who shall
be documented that the technical methods used reflect currently accepted
engineering practices. Studies, analyses, and computations shall be
submitted in sufficient detail to allow thorough review and approval.
C.
Within Zone AO, new construction and substantial improvements shall have the lowest floor (including basement) elevated above the highest adjacent grade at least as high as the depth number specified in feet on the community's Flood Insurance Rate Map enumerated in § 182-3.2, plus two feet of freeboard, or not less than three feet if a depth number is not specified.
D.
Within Zones AH and AO, adequate drainage paths are required to guide
floodwaters around and away from proposed structures on slopes.
The following standards, in addition to the requirements in § 182-5.1A, Subdivision proposals, and § 182-5.1B, Encroachments, and § 182-5.2, Standards for all structures, apply to new and substantially improved commercial, industrial and other nonresidential structures located in areas of special flood hazard.
A.
Within Zones A1-A30, AE and AH and also Zone A, if base flood elevation
data is available, new construction and substantial improvements of
any nonresidential structure shall either:
(1)
Have the lowest floor, including basement or cellar, elevated
to or above two feet above the base flood elevations; or
(2)
Be floodproofed so that the structure is watertight below two
feet above the base flood elevation, including attendant utility and
sanitary facilities, with walls substantially impermeable to the passage
of water. All structural components located below the base flood level
must be capable of resisting hydrostatic and hydrodynamic loads and
the effects of buoyancy.
B.
Within Zone AO, new construction and substantial improvements of
nonresidential structures shall:
(1)
Have the lowest floor (including basement) elevated above the
highest adjacent grade at least as high as the depth number specified
in feet on the community's FIRM, plus two feet (at least three feet
if no depth number is specified); or
(2)
Together with attendant utility and sanitary facilities, be completely floodproofed to that level to meet the floodproofing standard specified in § 182-5.4A(2).
C.
If the structure is to be floodproofed, a licensed professional engineer or architect shall develop and/or review structural design, specifications and plans for construction. A floodproofing certificate or other certification shall be provided to the local administrator that certifies that the design and methods of construction are in accordance with accepted standards of practice for meeting the provisions of § 182-5.4A(2), including the specific elevation (in relation to mean sea level) to which the structure is to be floodproofed.
D.
Within Zones AH and AO, adequate drainage paths are required to guide
floodwaters around and away from proposed structures on slopes.
E.
Within Zone A, when no base flood elevation data is available, the
lowest floor (including basement) shall be elevated at least three
feet above the highest adjacent grade.
The following standards, in addition to the standards in § 182-5.1, General standards, and § 182-5.2, Standards for all structures, apply, as indicated, in areas of special flood hazard to manufactured homes and to recreational vehicles which are located in areas of special flood hazard.
A.
B.
A manufactured home that is placed or substantially improved in Zones
A1-A30, AE and AH and Zone A shall be elevated on a permanent foundation
such that the bottom of the frame of the manufactured home chassis
is elevated to or above two feet above the base flood elevation and
is securely anchored to an adequately anchored foundation system to
resist flotation, collapse and lateral movement.
The following standards apply to new and substantially improved accessory structures, including detached garages, in the areas of special flood hazard shown on the Flood Insurance Rate Map designated in § 182-3.2.
A.
Within Zones A1-A30, AE, AO, AH, and A, accessory structures must meet the standards of § 182-5.2A, Anchoring.
B.
Within Zones A1-A30, AE, and AH, and also Zone A, if base flood elevation
data are available, areas below two feet above the base flood elevation
shall be constructed using methods and practices that minimize flood
damage.
C.
Within Zones AO and Zone A, if base flood elevation data are not
available, areas below three feet above the highest adjacent grade
shall be constructed using methods and practices that minimize flood
damage.
D.
Structures must be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for entry and exit of floodwaters in accordance with § 182-5.2B(3).
In order to prevent potential flood damage to certain facilities
that would result in serious danger to life and health, or widespread
social or economic dislocation, no new critical facility shall be
located within any area of special flood hazard, or within any 500-year
flood zone shown as a B Zone or a Shaded X Zone on the community's
Flood Insurance Rate Maps.
