A.Â
For any proposed subdivision or land development, the owner/developer shall submit phased stormwater management plans to the Dorchester County Department of Public Works for review and approval. At a minimum, plans shall be submitted for the sketch, preliminary and final land development phases of project design. Each plan submittal shall include the minimum content specified in § 134-14 of this chapter and meet the requirements of the Design Manual and Article IV of this chapter.
B.Â
The Dorchester County Department of Public Works shall perform a
comprehensive review of the stormwater management plans for each phase
of site design. Coordinated comments will be provided for each plan
phase that reflect input from all appropriate agencies, including
but not limited to the Soil Conservation District (SCD), the Departments
of Planning and Zoning, Public Works and Health. All comments from
the Dorchester County Department of Public Works and other appropriate
agencies shall be addressed and approval received at each phase of
project design before subsequent submissions.
C.Â
All plan submissions shall be made to the Dorchester County Planning
and Zoning Department, which shall coordinate planning reviews with
the appropriate reviewing agencies.
D.Â
The applicant for submission of a minor residential subdivision may request a waiver of the requirement to submit a preliminary plan in accordance with § 134-14B if environmental site design practices have been fully utilized.
E.Â
The subdivision and land development of a one-lot single-family residential unit utilizing the application of preapproved environmental site design features may utilize a standard stormwater management plan approved by the Dorchester County Department of Public Works as an alternative to the requirements of §§ 134-13 and 134-14.
F.Â
Notification of approval or reasons for disapproval or modification
shall be given to the applicant within 30 days after submission of
a complete stormwater plan. If a decision is not made within 30 days,
the applicant or designated representative shall be informed of the
status of the review process and the anticipated completion date.
The stormwater management plan shall not be considered approved without
the inclusion of the signature and date of signature of the Director
of the Dorchester County Department of Public Works on the plan.
A.Â
The owner/developer shall submit a sketch plan that provides sufficient information for an initial assessment of the proposed project and whether stormwater management can be provided according to § 134-11 of this chapter and the Design Manual. Plans submitted for sketch plan approval shall include but are not limited to:
(1)Â
A location map, for the purpose of locating the project site to be
developed, at a minimum scale of 2,000 feet to the inch, showing the
relation of the tract to adjoining property and to all streets and
municipal boundaries existing within 1,000 feet of any part of the
tract of land on which the project site is proposed to be developed;
(2)Â
The proposed name or identifying title of the project along with
plan date, date of latest revision, North point, graphic scale and
written scale. All plans shall be drawn at a common engineering scale;
(3)Â
Total acreage of the project site and the tract of land on which
the project site is located;
(4)Â
The proposed land use, number of lots and dwelling units and the
extent of commercial, industrial or other residential uses;
(5)Â
The name and address of the landowner and developer of the project
site;
(6)Â
The names of all owners of all immediately adjacent land, the names
of all proposed or existing developments immediately adjacent, and
the locations and dimensions of any adjacent streets or easements;
(7)Â
A site plan at a scale specified by the Dorchester County Department
of Public Works showing development site location, existing natural
features, water and other sensitive resources, topography, and natural
drainage patterns;
(8)Â
The location of any existing private and public drainage easements
and culvert pipes, including the designation of state and federal
regulated water bodies and streams;
(9)Â
The anticipated location and area computation of all proposed impervious
areas, buildings, roadways, parking, sidewalks, utilities, and other
site improvements;
(10)Â
The location of the proposed limit of disturbance (LOD), soil
types as designated by the USDA Natural Resources Conservation Service
for Dorchester County, wetlands, forest conservation areas, floodplain,
steep slopes, and other areas to be protected during construction;
(11)Â
The boundary and designation of any critical areas;
(12)Â
Preliminary estimates of stormwater management requirements,
the selection and location of environmental site design practices
to be used, and the location of all proposed points of discharge from
the site;
(13)Â
A narrative that supports the sketch plan design and describes
how environmental site design will be implemented to the maximum extent
practicable;
(14)Â
A certificate for review by the Dorchester County Department
of Public Works;
(15)Â
A certificate of approval by the Dorchester County Department
of Public Works; and
(16)Â
Any other information required by the Dorchester County Department
of Public Works.
B.Â
Following sketch plan approval by the Dorchester County Department
of Public Works, the owner/developer shall submit preliminary land
development plans that reflect comments received during the previous
review phase. Plans submitted for preliminary land development approval
shall be of sufficient detail to allow site development to be reviewed
and include but not be limited to:
(1)Â
All information provided during the sketch plan review phase;
(2)Â
Final site layout, exact impervious area locations and acreages,
proposed topography with contour lines at one-foot intervals for slopes
of 5% or less or two-foot intervals for more steeply sloped land,
delineated drainage areas at all points of discharge from the site;
(3)Â
A written and bound hydrologic and hydraulic report including or
prepared in accordance with the following:
(a)Â
Stormwater runoff calculations for both pre-development and
post-development conditions for peak discharge and pollutant removal;
(b)Â
Stormwater volume computations for environmental site design
practices and quantity control structure;
(c)Â
Geotechnical investigations, including soil maps, borings, site-specific
recommendations, and any additional information necessary for the
final stormwater management design;
(d)Â
Hydrologic computations of the applicable environmental site
design and unified sizing criteria according to the Design Manual
for all points of discharge from the site;
(e)Â
Hydraulic and structural computations for all environmental
site design practices and structural stormwater management measures
to be used;
(f)Â
For all proposed detention basins and retention basins, and
temporary sedimentation basins, the documentation shall include a
plotting or tabulations of storage volumes with corresponding water
surface elevations and the outflow rates for those water surfaces;
(g)Â
A plan showing the delineation of pre- and post-development
drainage areas, including the path used to determine the time of concentration;
(h)Â
An analysis of all existing and proposed drainage conveyance
facilities capacity. The analysis shall include any off-site watercourses
determined to be potentially impacted by the Dorchester County Department
of Public Works;
(i)Â
A narrative that supports the final stormwater management design;
and
(j)Â
Any other information required by the Dorchester County Department
of Public Works.
(4)Â
A proposed erosion and sediment control plan that contains the construction
sequence, any phasing necessary to limit earth disturbances and impacts
to natural resources and an overlay plan showing the types and locations
of environmental site design and erosion and sediment control practices
to be used;
(5)Â
A narrative that supports the preliminary land development design,
describes how environmental site design will be used to meet the minimum
control requirements, and justifies any proposed structural stormwater
management measure; and
(6)Â
Any other information required by the approving agency.
C.Â
Following preliminary land development approval by the Dorchester
County Department of Public Works, the owner/developer shall submit
final erosion and sediment control and stormwater management plans
that reflect the comments received during the previous review phase.
Plans submitted for final approval shall be of sufficient detail to
allow all approvals and permits to be issued according to the following:
(1)Â
All information provided during the preliminary plan review phase;
(2)Â
Final erosion and sediment control plans shall be submitted according
to COMAR 26.17.01.05;
(3)Â
Final stormwater management plans shall be submitted for approval
in the form of construction drawings and be accompanied by a report
that includes sufficient information to evaluate the effectiveness
of the proposed runoff control design;
(4)Â
An engineer's cost opinion for construction of all stormwater management
facilities and practices;
(5)Â
A signed stormwater permit application;
(6)Â
Payment of permit fees. Permit fees will be determined after review
of the cost opinion; and
(7)Â
Submittal of any required maintenance, conservation and development
improvement agreements;
D.Â
Construction drawings submitted for final stormwater management plan
approval shall include but are not limited to:
(1)Â
A location map in accordance with § 134-14A(1);
(2)Â
Existing and proposed topography and proposed drainage areas, including
areas necessary to determine downstream analysis for proposed stormwater
management facilities;
(3)Â
Any proposed improvements, including location of buildings or other
structures, impervious surfaces, storm drainage facilities, and all
grading;
(4)Â
The location of existing and proposed structures and utilities;
(5)Â
Any easements and rights-of-way;
(6)Â
A note on the plan indicating the ownership and maintenance responsibilities
for all stormwater management facilities;
(7)Â
The delineation along with the signature and date of the person responsible,
if applicable, of any on-site wetlands;
(8)Â
The delineation and basis for determination of the one-hundred-year
floodplain;
(9)Â
Structural and construction details, including representative cross
sections for all components of the proposed drainage system or systems,
and stormwater management facilities;
(10)Â
All necessary construction specifications;
(11)Â
A sequence of construction;
(12)Â
Data for total site area, disturbed area, new impervious area,
and total impervious area;
(13)Â
A table showing the environmental site design and unified sizing
criteria volumes required in the Design Manual;
(14)Â
A table of materials to be used for stormwater management facility
planting;
(15)Â
All soil boring logs and locations;
(16)Â
An inspection and maintenance schedule;
(17)Â
Certification by the owner/developer that all stormwater management
construction will be done according to this plan;
(18)Â
A note that record drawings will be provided within 90 days
following completion of construction;
(19)Â
A record drawing certification signature block to be executed
after project completion;
(20)Â
A certificate for review by the Dorchester County Department
of Public Works;
(21)Â
The plans need to identify the person responsible for preparation
of the stormwater management plan; and
(22)Â
Any other information required by the Dorchester County Department
of Public Works.
A.Â
The design of stormwater management plans shall be prepared by any
individual whose qualifications are acceptable to the Dorchester County
Department of Public Works. The design shall be prepared by a professional
engineer, professional land surveyor, or landscape architect licensed
in the state, as necessary to protect the public or the environment.
B.Â
If a stormwater best management practice requires either a dam safety
permit from the Maryland Department of the Environment or small pond
approval from the soil conservation district, the Dorchester County
Department of Public Works shall require that the design be prepared
by a professional engineer licensed in the state.