[See also Ch. 27, Zoning, Part 11, Floodplain Districts]
[Ord. 8-4-81B, 8/4/1981, Article I]
In order to prevent excessive damage to buildings and structures
due to conditions of flooding, the following restrictions shall apply
to construction, development, and substantial improvements occurring
in any designated Floodplain Districts.
1.
Basements and First Floors.
A.
Lowest floor levels including basements in non-residential structures
and substantial improvements thereto shall be constructed at or above
an elevation of two feet above the Regulatory Flood or they may be
constructed below the level of the one-hundred-year flood provided
that they are floodproofed and designed to preclude inundation to
an elevation of at least two feet above the Regulatory Flood Elevation
and to withstand the hydrostatic and hydrodynamic load of the Regulatory
Flood.[1]
[1]
Note should be made of the publication entitled, "Flood-Proofing
Regulations" prepared by the U.S. Army Corps of Engineers, which contains
extensive information which can be of substantial benefit to municipalities
in regulating activities in areas subject to flooding.
B.
The lowest floor levels including basements in residential structures
and substantial improvements thereto shall be constructed at or above
an elevation of two feet above the Regulatory Flood Elevation.
2.
Fill. If fill is used to raise the finished surface of the lowest
floor two feet above the Regulatory Flood Elevation:
A.
Fill shall extend laterally 15 feet beyond the building line from
all points;
B.
Fill shall consist of soil or small rock materials only. Sanitary
land fills shall not be permitted.
C.
Fill material shall be compacted to provide the necessary permeability
and resistance to erosion, scouring, or settling;
D.
Fill slopes shall be no steeper than one vertical on two horizontal,
unless substantiating data, justifying steeper slopes are submitted
to and approved by the Zoning Officer;
E.
Fill shall be used only to the extent to which it does not adversely
affect adjacent properties.
3.
Placement of Buildings and Structures.
A.
All building and structures, including mobile homes, shall be constructed
and placed on the lot so as to offer the minimum obstruction to the
flow of water and shall be designed to have a minimum effect upon
the flow and height of flood water.
B.
The following shall not be placed or caused to be placed in any of
the designated Floodplain Districts: Fences, except two-wire fences,
other structures, or other matter which may impede, retard, or change
the direction of the flow of water, or that will catch or collect
debris carried by such water, or that is placed where the natural
flow of the stream of flood waters would carry the same downstream
to the damage or detriment of either public or private property adjacent
to the floodplain.
4.
Anchoring.
A.
All buildings, mobile homes, and structures shall be firmly anchored
in accordance with accepted engineering practices to prevent flotation,
collapse, or lateral movement, thus reducing the threat to life and
property and decreasing the possibility of the blockage of bridge
openings and other restricted sections of the watercourse.
B.
All air ducts, large pipes and storage tanks located at or below
the Regulatory Flood Elevation shall be firmly anchored to prevent
flotation, collapse, or lateral movement.
5.
Mobile Home - Special Anchoring and Site Requirements. All mobile
homes to be located in any designated Floodplain District shall be
anchored to resist flotation, collapse, or lateral movement by providing
over-the-top and frame ties to ground anchors as well as additional
precautions in the following manner:
A.
Over-the-top ties shall be provided at each of the four corners of
the mobile home, with two additional ties per side at intermediate
locations and mobile homes less than 50 feet long requiring one additional
tie per side.
B.
Frame ties shall be provided at each corner of the home with five
additional ties per side at intermediate points for mobile homes 50
feet or more in length and mobile homes less than 50 feet long requiring
four additional ties per side.
C.
All components of the anchoring system shall be capable of carrying
a force of 4,800 pounds.
D.
Any additions to mobile homes shall be similarly anchored.
E.
All individual mobile homes, new mobile home parks and mobile home
subdivisions, expansion to existing mobile home parks and mobile home
subdivisions, existing mobile home parks and mobile home subdivisions
where the repair, reconstruction, or improvement of the streets, utilities
and pads equals or exceeds 50% of the value of the streets, utilities,
and pads before the repair, reconstruction, or improvements have commenced,
shall be located and/or designed so that:
G.
An evacuation plan indicating alternate vehicular access and escape
routes for mobile home parks and mobile home subdivisions shall be
filed with the appropriate local officials where appropriate.
H.
Mobile homes shall not be placed in the Floodway or Approximated
Floodplain Districts, except in existing mobile home parks and existing
mobile home subdivisions.
6.
Floors, Walls, and Ceilings.
A.
Wood flooring used at or below the lowest floor level shall be installed
to accommodate a lateral expansion of the flooring, perpendicular
to the flooring grain, without incurring structural damage to the
building.
B.
Plywood used at or below the lowest floor level shall be of any exterior
or marine grade and of a water-resistant or waterproof variety.
C.
Basement ceilings in non-residential structures shall have sufficient
wet strength and be so installed as to survive inundation.
D.
Window frames, door frames, and door jambs used at or below the lowest
floor level shall be made of metal.
7.
Electrical Systems.
A.
All electric water heaters, electric furnaces, electric air conditioning
and ventilating systems, and other critical electrical installation
shall be permitted only at elevations of two feet or more above the
Regulatory Flood Elevation.
B.
No electrical distribution panels shall be allowed at an elevation
of less than two feet above the level of the Regulatory Flood Elevation.
C.
Separate electrical circuits shall serve lower levels and shall be
dropped from above.
8.
Plumbing.
A.
Water heaters, furnaces and other critical mechanical installations
shall be permitted only at elevations of two feet or more above the
Regulatory Flood Elevation.
B.
No part of any on-site sewage disposal system shall be constructed
within any Floodplain District.
C.
Water supply systems and sanitary sewage systems shall be designed
and located to preclude infiltration of flood waters into the system
and discharges from the system into flood water.
D.
All gas and oil supply systems shall be designed to preclude the
infiltration of flood waters into the system and discharges from the
systems into flood waters. Additional provisions shall be made for
the drainage of these systems in the event that flood water infiltration
occurs.
9.
Paints and Adhesives.
A.
Adhesive used at or below the lowest floor level shall have a bonding
strength that is unaffected by inundation.
B.
Doors and all wood trim at or below the lowest floor level shall
be sealed with a waterproof paint or similar product.
C.
Paints or other finishes used at or below the lowest floor level
shall be capable of surviving inundation.
[Ord. 8-4-81B, 8/4/1981, Article II]
To insure that the aforementioned flood damage controls are
being employed in all construction, development, and substantial improvements
within any Floodplain District, the Zoning Officer shall provide the
applicant with information concerning the location of the Floodway,
Flood Fringe, and Approximated Floodplain District boundary relative
to his proposed construction and the water surface elevation of the
Regulatory Flood at the proposed construction site.
1.
Plan Requirements. The Zoning Officer shall require the following
specific information to be included as part of an application for
a building permit and shall maintain a permanent record of all such
information.
A.
A plan which details size of structure, finished ground elevation,
finished floor elevation, elevation of lowest floor (including basement),
whether or not such structures contain a basement, the elevation of
the first floor and other elevations which indicate the level of floodproofing.
B.
A document certified by a registered professional engineer or architect
that the design of any proposed building or structure, and plans for
the proposed development of the site comply with the provisions of
this Part 1 and any other applicable ordinance and that the floodproofing
measures applied to such development are adequate to withstand flood
depths and pressures, velocities, impacts, and uplift forces, and
any other factors associated with the Regulatory Flood.
C.
A record of such certificates indicating the specific elevation (in
relation to National Geodetic Vertical Datum of 1929) to which such
structures are floodproofed shall be maintained by the Zoning Officer.
D.
All other necessary governmental permits such as those required by
state and federal law including Federal Water Pollution Control Act
Amendments of 1972 (33 U.S.C. 1334) shall be presented for review
upon permit application.
2.
Review by the County Conservation District.
A.
A copy of all plans for proposed development in any designated Floodplain
District shall be submitted by the Zoning Officer to the County Conservation
District for review and comment prior to the issuance of a permit.
The recommendations of the County Conservation District may be incorporated
into the plan to provide for protection against predictable hazards.
[Ord. 8-4-81B, 8/4/1981, Article III]
The Approximated Floodplain District shall be that floodplain
area for which no specific flood profiles have been provided. Where
the specific one-hundred-year flood elevation cannot be determined
for this area using other sources of data such as the U.S. Army Corps
of Engineers, Flood Plain Information Reports, U.S. Geological Survey
Flood Prone Quadrangles, etc., then the applicant for the proposed
use, development and/or activity shall determine this elevation in
accordance with hydrologic and hydraulic engineering techniques. Consideration
shall be given to the methods specified by the U.S. Water Resource
Council's Technical Bulletin No. 17. This elevation information shall
be subject to review by the Municipality and other agencies that it
shall designate such as the Corps of Engineers, the Department of
Environmental Resources, a River Basin Commission, etc.
The term "construction" shall include the building, reconstruction,
extension, expansion, alteration, substantial improvements, erection
or relocation of a building or structure, including mobile homes.
For floodplain purposes, "construction" includes structures for which
the "start of construction" commenced on or after the effective date
of a floodplain management regulation adoption by the municipality.
The zoning district that establishes the bounds of the one-hundred-year
floodplain as identified by the Federal Insurance Administrator with
flood elevations so that necessary floodplain management control measures
can be instituted in flood prone areas. This district has been divided
into three subdistricts: The Floodway, Flood Fringe, and Approximated
Floodplain District.
Any combination of structural and non-structural additions,
changes, or adjustments to structures which reduce or eliminate flood
damage to real estate or improved real property, water and sanitary
facilities, structures and their contents. It is additionally defined
as constructing or altering a structure to be watertight with walls
substantially impermeable to the passage of water. Furthermore, structural
components have the capability of resisting hydrostatic and hydrodynamic
loads and the effects of buoyancy. (See the Army Corps of Engineers
publication concerning Floodproofing, June 1972 for details on floodproofing
methods.)
A transportable, single family dwelling intended for permanent
occupancy, office or place of assembly contained in one unit or in
two units, designed to be joined into one integral unit capable of
again being separated for repeated towing, which arrives at a site
complete and ready for occupancy except for minor and incidental unpacking
and assembly operations, and constructed 80 that it may be used without
a permanent foundation.
A flood that, on the average, is likely to occur once every
100 years (i.e. that has a 1% chance of occurring each year, although
the flood may occur in any year).
The flood which has been selected to serve as the basis upon
which the floodplain management provisions of this and other ordinances
have been prepared, for the purposes of this Ordinance, the one-hundred-year
flood, as defined by the Federal Insurance Administrator.
The one-hundred-year flood elevation based upon the information
contained in the Official Flood Insurance Study. Where flood elevations
have not been provided, the regulatory flood elevation shall be the
elevation at a point on the boundary of the identified floodplain
area which is nearest to the construction site in question.
Any reconstruction, major alteration, or improvement (not
including general maintenance or repair) of a structure, the cost
of which equals or exceeds 50% of the market value of the structures
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 Ordinance, substantial improvement
is considered to have occurred 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. The term does not, however, include either (1) any
project for improvement of a structure to comply with existing or
local health, sanitary, or safety code specifications which are solely
necessary to assure safe living conditions or (2) any alteration of
a structure listed on the National Register of Historic Places or
a State Inventory of Historic Places.
