In addition to the general requirements of Article
IV, the requirements of this section shall:
A. Apply in flood hazard areas that are not identified as coastal high-hazard
areas (V Zones) and Coastal A Zones. These flood hazard areas, referred
to collectively as "A Zones," include special flood hazard areas along
nontidal waters of the state, landward of coastal high-hazard areas
(V Zones), and landward of Coastal A Zones (if delineated).
B. Apply to all development, new construction, substantial improvements
(including repair of substantial damage), and placement, replacement,
and substantial improvement (including repair of substantial damage)
of manufactured homes.
Within areas defined by flood protection setbacks along nontidal
waters of the state:
A. No new buildings, structures, or other development shall be permitted
unless the applicant demonstrates that the site cannot be developed
without such encroachment into the flood protection setback and the
encroachment is the minimum necessary after consideration of varying
other siting standards such as side, front, and back lot line setbacks.
B. Disturbance of natural vegetation shall be minimized and any disturbance
allowed shall be vegetatively stabilized.
C. Public works and temporary construction may be permitted.
New residential structures and residential portions of mixed use structures, and substantial improvement (including repair of substantial damage) of existing residential structures and residential portions of mixed use structures shall comply with the applicable requirements of Article
IV and this section. See §
149-36 for requirements for horizontal additions.
A. Elevation requirements.
(1) Lowest floors shall be elevated to or above the flood protection
elevation.
(2) In areas of shallow flooding (Zone AO), the lowest floor (including
basement) shall be elevated at least as high above the highest adjacent
grade as the depth number specified in feet on the FIRM plus two feet,
or at least four feet if a depth number is not specified.
(3) Enclosures below the lowest floor shall meet the requirements of Subsection
C.
B. Limitations on use of fill to elevate structures. Unless otherwise restricted by these regulations, especially by the limitations in §
149-33A,
B and
C, fill placed for the purpose of raising the ground level to support a building or structure shall:
(1) Consist of earthen soil or rock materials only.
(2) Extend laterally from the building footprint to provide for adequate
access as a function of use; the Floodplain Administrator may seek
advice from the State Fire Marshal's office and/or the local
fire services agency;
(3) Comply with the requirements of the building code and be placed and
compacted to provide for stability under conditions of rising and
falling floodwaters and resistance to erosion, scour, and settling;
(4) Be sloped no steeper than one vertical to two horizontal, unless
approved by the Floodplain Administrator;
(5) Be protected from erosion associated with expected velocities during
the occurrence of the base flood; unless approved by the Floodplain
Administrator, fill slopes shall be protected by vegetation if the
expected velocity is less than five feet per second, and by other
means if the expected velocity is five feet per second or more; and
(6) Be designed with provisions for adequate drainage and no adverse
effect on adjacent properties.
C. Enclosures below the lowest floor.
(1) Enclosures below the lowest floor shall be used solely for parking
of vehicles, building access, crawl/underfloor spaces, or limited
storage.
(2) Enclosures below the lowest floor shall be constructed using flood-damage-resistant
materials.
(3) Enclosures below the lowest floor shall be provided with flood openings
which shall meet the following criteria: (NOTE: See NFIP Technical
Bulletin No. 1, "Openings in Foundation Walls and Walls of Enclosures."]
(a)
There shall be a minimum of two flood openings on different
sides of each enclosed area; if a building has more than one enclosure
below the lowest floor, each such enclosure shall have flood openings
on exterior walls.
(b)
The total net area of all flood openings shall be at least one
square inch for each square foot of enclosed area (nonengineered flood
openings), or the flood openings shall be engineered flood openings
that are designed and certified by a licensed professional engineer
to automatically allow entry and exit of floodwaters; the certification
requirement may be satisfied by an individual certification or an
evaluation report issued by the ICC Evaluation Service, Inc.
(c)
The bottom of each flood opening shall be one foot or less above
the higher of the interior floor or grade, or the exterior grade,
immediately below the opening.
(d)
Any louvers, screens or other covers for the flood openings
shall allow the automatic flow of floodwaters into and out of the
enclosed area.
(e)
If installed in doors, flood openings that meet requirements of Subsection
C(3)(a) through
(d), are acceptable; however, doors without installed flood openings do not meet the requirements of this section.
New nonresidential structures and nonresidential portions of mixed use structures, and substantial improvement (including repair of substantial damage) of existing nonresidential structures and nonresidential portions of mixed use structures shall comply with the applicable requirements of Article
IV and the requirements of this section. See §
149-36 for requirements for horizontal additions.
A. Elevation requirements. Elevated structures shall:
(1) Have the lowest floor (including basement) elevated to or above the
flood protection elevation; or
(2) In areas of shallow flooding (Zone AO), have the lowest floor (including
basement) elevated at least as high above the highest adjacent grade
as the depth number specified in feet on the FIRM plus two feet, or
at least four feet if a depth number is not specified; and
(3) Have enclosures below the lowest floor, if any, that comply with the requirements of §
149-34C; or
(4) If proposed to be elevated on fill, meet the limitations on fill in §
149-34B.
B. Floodproofing requirements.
(1) Floodproofing of new nonresidential buildings:
(a)
Is not allowed in nontidal waters of the state [COMAR 26.17.04.11(B)(7)].
(b)
Is not allowed in Coastal A Zones.
(2) Floodproofing for substantial improvement of nonresidential buildings:
(a)
Is allowed in nontidal waters of the state.
(b)
Is allowed in Coastal A Zones.
(3) If floodproofing is proposed, structures shall:
(a)
Be designed to be dry floodproofed such that the building or
structure is watertight with walls and floors substantially impermeable
to the passage of water to the level of the flood protection elevation
plus 1.0 foot; or
(b)
If located in an area of shallow flooding (Zone AO), be dry
floodproofed at least as high above the highest adjacent grade as
the depth number specified on the FIRM plus three feet, or at least
five feet if a depth number is not specified; and
(c)
Have structural components capable of resisting hydrostatic
and hydrodynamic loads and effects of buoyancy;
(d)
Have floodproofing measures that are designed taking into consideration
the nature of flood-related hazards; frequency, depth and duration
of flooding; rate of rise and fall of floodwater; soil characteristics;
flood-borne debris; at least 12 hours of flood warning time from a
credible source; and time necessary to implement any measures that
require human intervention;
(e)
Have at least one door above the applicable flood elevation
that allows human ingress and egress during conditions of flooding;
(f)
Have an operations and maintenance plan that is filed with local
emergency management officials and that specifies the owner/occupant's
responsibilities to monitor flood potential; the location of any shields,
doors, closures, tools, or other goods that are required for implementation;
maintenance of such goods; methods of installation; and periodic inspection;
and
(g)
Be certified by a licensed professional engineer or licensed architect, through execution of a floodproofing certificate that states that the design and methods of construction meet the requirements of this section. The floodproofing certificate shall be submitted with the construction drawings as required in §
149-15A(14).