All grading plans and specifications shall include the following
terms and conditions:
A.
The development shall be fitted to the topography and soils so as
to create the least erosion potential.
B.
The natural vegetation shall be retained and protected wherever possible.
C.
Only the smallest practical area shall be exposed for the shortest
practical period of time.
D.
Erosion control practices (such as interceptor ditches, berms, terraces,
contour ripping, soil erosion checks and sediment basins) shall be
installed to minimize soil and water losses.
E.
Temporary vegetation and/or mulching shall be used to protect critical
areas exposed during the time of development.
F.
During and after development, provisions shall be made to effectively
accommodate the increased runoff caused by changeable soil and surface
conditions and to not cause siltation of the receiving stream.
G.
Permanent vegetation and structures shall be installed in the development
as soon as the season permits.
In order to prevent abnormal or excessive grading, the following
additional requirements shall pertain to those areas where steep slopes
exist:
A.
All roads and streets shall be placed as close to the contour as
possible to minimize cutting and filling.
B.
The construction of all structures shall be preceded by the installation
of storm drainage system(s) and stabilization measures.
C.
In the case of a single lot development within such areas where no
central storm drainage system exists, runoff from driveways, roofs
and other improved surfaces shall be diverted and carried to an acceptable
outlet by one or a combination of the following methods: filtration
beds, subsurface dry wells, storm drainage systems and/or underground
conduit systems or other adequate or protected outlets.
D.
The extent of cutting and filling that will be permitted on any lot
will be based on the soil conditions at the site and as determined
by the Department of Code Enforcement, upon recommendation of the
Soil Conservation District or the Department of the Environment for
the State of Maryland. Construction on piling and/or supports shall
be permitted.
[Amended 3-4-1991 by Ord. No. 2-1-91]
Vegetative erosion and sediment control measures shall include
but not be limited to the following:
A.
Temporary vegetative stabilization. Areas where grading or cutting
and filling operations are carried out in several stages that expose
soil for prolonged periods of time (up to one year) to erosion shall
be temporarily stabilized by seeding. The necessary steps to be followed
to attain an adequate erosion control coverage with temporary seeding
shall be as follows:
C.
Mulching final grade. The necessary steps to protect soil from erosion
after final grading where permanent seeding is delayed until the next
season shall be as follows:
(1)
Installation of erosion control practices as previously provided
or required.
(2)
Application of required lime and fertilizer.
(3)
Preparation of final seedbed.
(4)
Mulching, as required.
(5)
Mulch anchoring, as required.
(6)
Permanent seeding shall be established during the first season following
mulching.
D.
Permanent vegetative stabilization. Adapted grasses, legumes and
other plants are available for stabilizing exposed areas. The final
choice of species should be determined by considering such factors
as adaptability to climate, soils and terrain and degree of maintenance.
Steps necessary to establish permanent vegetative stabilization are
as follows:
Structural erosion and sediment control measures shall include
but not be limited to the following:
A.
Diversions. The number of diversions and the physical extent and
spacing are dependent upon the land slope, soil and runoff. The surface
runoff shall be collected and conveyed laterally along the diversion
at nonerosive and nonscouring velocities and discharged into a protected
area or outlet channel.
B.
Bench terraces.
C.
Outlet channels. Outlet channels are constructed for the disposal
of storm runoff from diversions, bench terraces and other structures.
The design is based upon the runoff from predicted storm frequency
and includes the vegetative or structural measures required to protect
the channel from scour and erosion.
D.
Waterway stabilization structures. Structural devices such as drop
structures, grade stabilization structures and channel liners should
be utilized to dissipate the energy of flowing water by holding the
water slopes and velocities within nonscouring limits.
E.
Channel bank stabilization. Channel bank stabilization provides a
barrier that will withstand the erosive forces exerted by flowing
water or create a bank roughness that will reduce the erosive power
by dissipating the energy of the water as it moves along the bank
line. Methods commonly used include riprap, rock cribs (gabions),
groins, jetties, fencing, piling, etc.
F.
Stream channel improvement. Stream channel improvement may require
the straightening, realignment or the construction of a new channel
to designed cross section and grade, as necessary. The design shall
include considerations regarding the stability of the bed and banks
of the proposed channel under the predicted runoff conditions.
G.
Sediment basins. "Sediment basins" are temporary earth-fill-type
dams constructed downstream from a development area which serve to
regulate runoff and trap sediment. Sediment shall be removed mechanically
as the basin behind the dam becomes filled. The structure can be removed
once stability is reached in the development area.
H.
Installation and maintenance. The installation and maintenance of the specified erosion and sediment control measures shall be accomplished in accordance with the procedures as set forth in § 233-23.
I.
Cut and fill slopes. The face of all such slopes shall be planted or otherwise protected from erosion prior to the release of the permit obligations. Responsibility shall remain on the permittee until such planting is well-established in accordance with § 233-23. Other exposed areas susceptible to erosion shall be similarly protected.
[Amended 3-4-1991 by Ord. No. 2-1-91]
Approval for clearing and grading shall be obtained from the Department of Code Enforcement subject to the granting of temporary easements and other conditions deemed necessary by said Department in order to inspect and enforce the performance of the specified erosion and sediment control measures provided for in this Article V.
The grading plans and specifications shall specify and delineate
the use and extent of fills in accordance with the following classifications:
A.
Type I fill: load-bearing fills proposed for support of buildings,
walls and other structures, the function thereof which would be especially
impaired by settlement.
[Amended 3-4-1991 by Ord. No. 2-1-91]
B.
Type II fill: load-bearing fills proposed for support of roadways,
pavements, utility lines and structures which would not be especially
impaired by moderate settlement.
C.
Type III fill: common fills proposed for landscaping or for other
non-load-bearing usage.
All load-bearing fills shall meet the following requirements:
A.
No inclusions of organic or other deleterious materials which may
be subject to decay shall be permitted. All fills shall also be free
of inclusions of ice or snow.
B.
No rock or similar irreducible material with a maximum dimension
greater than eight inches shall be buried or placed in any load-bearing
fill within two feet of finished grade or within two feet of foundation
base elevation. When such material is placed in fills, it shall be
done under the direction and supervision of an engineer.
A.
The natural ground surface shall be prepared to receive fill by removing
all organic surface materials, noncomplying fill and unsuitable soils
in accordance with the following provisions, except as otherwise approved
by the Department of Code Enforcement and based on the recommendations
of the professional engineer.
[Amended 3-4-1991 by Ord. No. 2-1-91]
B.
Prior to placing Type I and Type II fills, the ground surface, if within five feet of finished grade or foundation base elevation, shall be compacted so as to achieve a density of not less than 90% of maximum density as defined under § 233-32 within the top six inches.
C.
No fill shall be placed on frozen ground.
All fills will be compacted in accordance with the following
provisions:
A.
All Type I and II fills shall be compacted to a minimum of 95% and
90%, respectively, of maximum density, as determined in the laboratory
by ASTM Test Method D1557-66T, also known as the "Proctor Test." Type
III fill shall be compacted sufficiently so as to be stable and to
prevent an erosion hazard.
B.
In-place (field) density shall be determined by ASTM test or the
American Society of State Highway and Transportation Officials (AASHTO)
equivalent test, Method D1556-64T, or by equivalent test(s) approved
by the Building Inspector.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. III)]
C.
Fills shall be placed in approximately horizontal layers, each having
a loose thickness of not more then eight inches.
Fills constructed predominantly of large rock, such as sandstone
and iron concretions, will be permitted only if the specifications
for such fill are prepared by and construction done under the direction
and supervision of an engineer.
A.
No fill shall be made which creates an exposed surface steeper in
slope than two horizontal to one vertical.
B.
The Department of Code Enforcement may require that the fill be constructed
with an exposed surface with a grade flatter than two horizontal to
one vertical or may require such other measures it deems necessary
for stability, vegetative establishment and maintenance and safety.
[Amended 3-4-1991 by Ord. No. 2-1-91]
C.
Fills toeing out on natural slopes at a grade steeper than three
horizontal to one vertical shall not be made unless approved by the
Department of Code Enforcement.
[Amended 3-4-1991 by Ord. No. 2-1-91]
Existing features which would add value to development of natural
or man-made assets of the Town, such as trees, watercourses, falls,
beaches, vistas, historic or architecturally significant buildings
and similar irreplaceable assets, should be preserved, insofar as
possible, through harmonious and careful development.
A.
Cuts shall not be more steep in slope than two horizontal to one
vertical.
B.
The Department of Code Enforcement shall require at any time that
the excavation be made with a cut face with a grade flatter than two
horizontal to one vertical, or said Department may require such other
measures as it deems necessary for stability, vegetative establishment
and safety.
[Amended 3-4-1991 by Ord. No. 2-1-91]
A.
Cut and fill slopes in excess of 30 feet but not more than 40 feet
in vertical height shall be terraced at approximate midheight. Terraces
in slopes with a vertical height greater than 40 feet shall be made
at equal vertical intervals not more than 20 feet apart. Depending
on soil conditions, terraces may be required of closer intervals by
the Department of Code Enforcement as it deems necessary for stability,
vegetative establishment and maintenance and safety. Bench terraces
shall be a minimum of five feet wide with an absolute minimum invert
gradient of 1% if sodded or 1/2% if paved and with a 10:1 lateral
slope towards the toe of the upper bank and must convey water with
minimum six-inch freeboard to an acceptable outlet.
[Amended 3-4-1991 by Ord. No. 2-1-91]
B.
Cuts and fills shall be set back from property lines and buildings
shall be set back from cut or fill slopes in accordance with the diagrams
entitled "Slope Setback from Property Line" and "Building Setback,"
which diagrams are incorporated herein by reference and a certified
copy of which shall permanently be kept on file in the office of the
Town Council of Indian Head.
C.
Fill placed above the top of an existing or proposed surface with
a slope steeper than three horizontal to one vertical shall be set
back from the top of the slope a minimum distance of six feet.
D.
The setbacks established by this section are minimum and, depending
on soil conditions, may be increased by the Department of Code Enforcement
if deemed necessary for safety or stability or to prevent possible
damage from water, soil or debris.
[Amended 3-4-1991 by Ord. No. 2-1-91]
E.
Notwithstanding anything to the contrary, the Department of Code
Enforcement may reduce the required setback where the necessity for
the setback may be eliminated or if the owner has a letter of authorization
to extend slopes onto the adjacent property.
[Amended 3-4-1991 by Ord. No. 2-1-91]
The following provisions apply to the conveyance and disposal
of surface water runoff:
A.
Disposal. All drainage facilities shall be designed to convey surface
water in such a manner as to prevent erosion, overflow or ponding.
Said water shall be conveyed to an acceptable outlet in accordance
with such applicable design criteria, standards and procedures as
required by the Town specifications. The ponding of water shall not
be permitted above cut or fill slopes or on drainage terraces. Adequate
drainage facilities shall be provided to prevent such ponding.
B.
Erosion prevention. The permittee and the owner shall make adequate
provisions to prevent any surface water and/or groundwater from materially
damaging the face of any cut or fill. All slopes shall be protected
from surface runoff from above by berms, swales or brow ditches.
C.
Grading around buildings. All areas shall be graded to provide for
positive drainage away from the building toward the approved disposal
area.
D.
Retention and infiltration. Subject to the requirements and recommendations
of the Charles County Soil Conservation District and the Department
of the Environment, measures such as infiltration beds, dry wells
and retention ponds may be used to allow stormwater runoff to percolate
into the soil.
