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.
A.
Development in designated floodways.
(1)
For proposed development that will encroach into a designated floodway, § 78-15A(7) requires the applicant to submit an evaluation of alternatives to such encroachment, including different uses of the site or the portion of the site within the floodway, and minimization of such encroachment. This requirement does not apply to fences that do not block the flow of floodwaters or trap debris.
(2)
Proposed development in a designated floodway may be permitted only
if:
(a)
The applicant has been issued a permit by MDE; and
(b)
The applicant has developed hydrologic and hydraulic engineering
analyses and technical data prepared by a licensed professional engineer
reflecting such changes, and the analyses, which shall be submitted
to the Floodplain Administrator, demonstrate that the proposed activity
will not result in any increase in the base flood elevation; or
(c)
If the analyses demonstrate that the proposed activities will
result in an increase in the base flood elevation, the applicant has
obtained a conditional letter of map revision and a letter of map
revision from FEMA upon completion of the project. Submittal requirements
and fees shall be the responsibility of the applicant.
B.
Development that includes the placement of fill in nontidal waters of the state. For proposed development that includes the placement of fill in nontidal waters of the state, other than development that is subject to Subsection D, a hydraulically-equivalent volume of excavation is required. Such excavations shall be designed to drain freely.
C.
Development in areas with base flood elevations but no designated
floodways. For development in special flood hazard areas of nontidal
waters of the state with base flood elevations but no designated floodways:
(1)
The applicant shall develop hydrologic and hydraulic engineering analyses and technical data reflecting the proposed activity and shall submit such technical data to the Floodplain Administrator as required in § 78-15A(6). The analyses shall be prepared by a licensed professional engineer in a format required by FEMA for a conditional letter of map revision and a letter of map revision upon completion of the project. Submittal requirements and fees shall be the responsibility of the applicant.
(2)
The proposed development may be permitted if the applicant has received
a permit by MDE and if the analyses demonstrate that the cumulative
effect of the proposed development, when combined with all other existing
and potential flood hazard area encroachments, will not increase the
base flood elevation more than 1.0 foot at any point.
D.
Construction of roads, bridges, culverts, dams and in-stream ponds.
Construction of roads, bridges, culverts, dams, and in-stream ponds
in nontidal waters of the state shall not be approved unless they
comply with this section and the applicant has received a permit from
MDE.
E.
Alteration of a watercourse.
(1)
For any proposed development that involves alteration of a watercourse not subject to Subsection C, unless waived by MDE, the applicant shall develop hydrologic and hydraulic engineering analyses and technical data reflecting such changes, including the floodway analysis required in § 78-15A, and submit such technical data to the Floodplain Administrator and to FEMA. The analyses shall be prepared by a licensed professional engineer in a format required by MDE and by FEMA for a conditional letter of map revision or letter of map revision. Submittal requirements and fees shall be the responsibility of the applicant.
(2)
Alteration of a watercourse may be permitted only upon submission,
by the applicant, of the following:
(a)
A description of the extent to which the watercourse will be
altered or relocated;
(b)
A certification by a licensed professional engineer that the
flood-carrying capacity of the watercourse will not be diminished;
(c)
Evidence that adjacent communities, the U.S. Army Corps of Engineers,
and MDE have been notified of the proposal, and evidence that such
notifications have been submitted to FEMA; and
(d)
Evidence that the applicant shall be responsible for providing
the necessary maintenance for the altered or relocated portion of
the watercourse so that the flood-carrying capacity will not be diminished.
The Floodplain Administrator may require the applicant to enter into
an agreement with the Town of Leonardtown specifying the maintenance
responsibilities; if an agreement is required, the permit shall be
conditioned to require that the agreement be recorded on the deed
of the property which shall be binding on future owners.
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 § 78-36 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.
B.
Limitations on use of fill to elevate structures. Unless otherwise restricted by these regulations, especially by the limitations in § 78-33A, § 78-33B, and § 78-33C, 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 #1, "Openings in Foundation Walls and Walls of Enclosures
Below Elevated Buildings."]
(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 (non-engineered
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.
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 § 78-36 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
B.
Floodproofing requirements.
(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 § 78-15A(13).
B.
In nontidal waters of the state that are subject to the regulatory authority of MDE, all horizontal additions shall comply with the applicable requirements of Article IV and this section and:
(1)
If the addition is structurally connected to the base building, the requirements of Subsection C apply.
(2)
If the addition has an independent foundation and is not structurally
connected to the base building and the common wall with the base building
is modified by no more than a doorway, the base building is not required
to be brought into compliance.
C.
For horizontal additions that are structurally connected to the base
building:
D.
For horizontal additions with independent foundations that are not
structurally connected to the base building and the common wall with
the base building is modified by no more than a doorway, the base
building is not required to be brought into compliance.
E.
A horizontal addition to a building or structure that is not substantial
improvement, and is not located in nontidal waters of the state, is
not required to comply with this section.
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[Note: See "Substantial Improvement/Substantial Damage Desk
Reference" (FEMA P-758).]
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A.
Accessory structures shall be limited to not more than 300 square
feet in total floor area.
B.
Accessory structures shall comply with the elevation requirements and other requirements of § 78-34, the floodproofing requirements of § 78-35B, or shall:
(1)
Be useable only for parking of vehicles or limited storage;
(2)
Be constructed with flood-damage-resistant materials below the base
flood elevation;
(3)
Be constructed and placed to offer the minimum resistance to the
flow of floodwaters;
(4)
Be anchored to prevent flotation;
(5)
Have electrical service and mechanical equipment elevated to or above
the base flood elevation; and
