In order to prevent excessive flood damage and to allow for the protection
of the natural and beneficial floodplain functions, the following provisions
shall apply to all development, new construction and substantial improvements
to existing structures in all floodplain zones. In the event that a structure
is in more than one (1) zone, the more stringent provision shall apply to
the entire structure.
In all floodplain zones, any development which proposes to alter a watercourse
shall obtain a variance. All conditions for encroachment in the floodway shall
be met and adverse impacts to aquatic resources shall be minimized. Adjacent
communities and property owners, FEMA and the Maryland Water Resources Administration
shall be notified by the applicant prior to any modification of a watercourse.
The Water Resources Administration of the Department of Natural Resources
may require a waterway construction permit.
In addition to the regulations found in §§
182-7 through 194-11, the following specific standards shall be applied:
A. Placement of building and materials. In general, buildings
and accessory structures should be located entirely out of the floodplain,
out of the flood protection setback or on land that is least susceptible to
flooding. All structures permitted in the floodplain shall be oriented so
as to offer the least resistance to the flow of floodwaters. Materials which
are buoyant, flammable, explosive, hazardous to health or which at times of
flooding may be injurious to human, animal or plant life shall not be stored
below the flood protection elevation.
B. Enclosures below lowest floor. Buildings which have been
elevated and have fully enclosed areas below the flood protection elevation,
as well as garages and accessory structures which are not elevated, shall
be constructed with water-equalizing vents which meet or exceed the following
standards:
(1) A minimum of two (2) openings on different walls having
a total net area of not less than one (1) square inch for every square foot
of enclosed area subject to flooding shall be provided.
(2) The bottom of all openings shall be no higher than one
(1) foot above grade.
(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 to equalize hydrostatic forces on the walls.
(4) Fully enclosed areas below the flood protection elevation
shall be used solely for parking of vehicles, access to the building or storage.
If such areas are enclosed, a nonconversion agreement shall be signed by the
applicant.
(5) In coastal high hazard areas, enclosures below the flood protection elevation shall comply with the provisions of §
182-11 of this chapter.
C. Manufactured homes and manufactured home parks.
(1) New manufactured homes and manufactured home parks shall be prohibited in the coastal high hazard area and in the floodway. In other floodplain zones, all new, replacement or substantially improved manufactured homes, whether in a manufactured home park or not, shall comply with §
182-9B of this chapter.
(2) Methods of anchoring shall include use of over the top
and frame ties to ground anchors. Pilings or columns shall be used to maintain
the storage capacity of the floodplain. Concrete block support pilings shall
be reinforced by placing reinforcing bars inside and extending them into the
footing, filling the hollows with cement and using mortar to cement the blocks
together. FEMA Publication 85, Manufactured Home Installation in Flood Hazard
Areas, should be consulted for specific recommendations.
(3) Manufactured homes repaired or replaced due to substantial flooding or other causes shall be considered new structures and shall fully comply with §
182-9B of this chapter.
(4) Owners of manufactured home parks or subdivisions that
are partially or fully within the floodplain shall file an evacuation plan
with the Director of Emergency Management. New manufactured home parks shall
provide an access road elevated to the flood protection elevation.
D. Anchoring. All structures shall be firmly anchored in
accordance with acceptable engineering practices to prevent flotation, collapse
and lateral movement during flooding. All air ducts, large pipes and storage
tanks located below the flood protection elevation shall be firmly anchored
to resist flotation.
E. Utilities.
(1) Electric. Distribution panel boxes shall be installed
at least two (2) feet above the flood protection elevation. All outlets and
electrical installations, such as heat pumps, air conditioners, water heaters,
furnaces, generators and distribution systems shall be installed at or above
the flood protection elevation.
(2) Plumbing. Toilets, sinks, showers, water heaters, pressure
tanks, furnaces and other permanent plumbing installations shall be installed
at or above the flood protection elevation.
(3) Gas. Gas meters and gas appliances shall be installed
at or above the flood protection elevation.
(4) Water supply and sanitary facilities. Water supply distribution
and sanitary disposal collection systems shall be designed to minimize or
eliminate the infiltration of floodwaters into the systems or discharges from
the systems into floodwaters and shall be located and constructed so as minimize
or eliminate flood damage. On-site sewage disposal systems shall meet these
same standards.