Code of Maryland Regulations › Title 26 - DEPARTMENT OF ENVIRONMENT › Part 3 - SUBTITLES 13-18 › Subtitle 17 - WATER MANAGEMENT › Chapter 26.17.02 - Stormwater Management › Section 26.17.02.09 - Stormwater Management Plans

Current through Register Vol. 51, No. 14, July 12, 2024
A.
				  The design of stormwater management plans shall be prepared by any individual
				  whose qualifications are acceptable to the approving agency. The approving
				  agency may require that the design be prepared by either a professional
				  engineer, professional land surveyor, or landscape architect licensed in the
				  State, as necessary to protect the public or the environment. If a stormwater
				  BMP requires either a dam safety permit from the Department or small pond
				  approval by the appropriate soil conservation district, the approving agency
				  shall require that the design be prepared by a professional engineer licensed
				  in the State.
B. Stormwater
				  management and development plans shall be consistent with adopted and approved
				  watershed management plans or flood management plans as approved by the
				  Department in accordance with the Flood Hazard Management Act of 1976
				  (Environment Article, Title 5, Subtitle 8, Annotated Code of
				  Maryland).
C. An operation and
				  maintenance plan shall be required as a condition of stormwater management plan
				  approval.
D. If a stormwater
				  management plan involves direction of some or all runoff off of the site, it is
				  the responsibility of the developer to obtain from adjacent property owners any
				  easements or other necessary property interests concerning flowage of water.
				  Approval of a stormwater management plan does not create or affect any right to
				  direct runoff onto adjacent property without that property owner's
				  permission.
E. Contents and
				  Submission of Stormwater Management Plans.
(1)
				  The owner/developer is responsible for submitting phased stormwater management
				  plans for development projects according to the comprehensive review and
				  approval process specified in Regulation .04 of this chapter, the Design
				  Manual, and county and municipal stormwater management ordinances. Plans shall
				  be submitted for the concept, site development, and final stormwater management
				  construction phases of project design. Comments from the appropriate approval
				  authority shall be addressed and approval received at each phase of project
				  design before subsequent submissions.
(2) The owner/developer shall submit a
				  concept plan that provides sufficient information for an initial assessment of
				  the proposed project and whether stormwater management can be provided
				  according to this chapter and the Design Manual. Plans submitted for concept
				  approval shall include, but are not limited to:
(a) A map at a scale specified by the
				  appropriate approval authority showing site location, existing natural
				  features, water and other sensitive resources, topography, and natural drainage
				  patterns;
(b) The anticipated
				  location of all proposed impervious areas, buildings, roadways, parking,
				  sidewalks, utilities, and other site improvements;
(c) The location of the proposed limit of
				  disturbance, erodible soils, steep slopes, and areas to be protected during
				  construction;
(d) Preliminary
				  estimates of stormwater management requirements, the selection and location of
				  ESD practices to be used, and the location of all points of discharge from the
				  site;
(e) A narrative that supports
				  the concept design and describes how ESD will be implemented to the MEP;
				  and
(f) Any other information
				  required by the approving Agency.
(3) Following concept plan approval by the
				  appropriate authority, the owner or developer shall submit site development
				  plans that reflect comments received during the previous review phase. Plans
				  submitted for site development approval shall be of sufficient detail to allow
				  site development to be reviewed and include but not be limited to:
(a) All information provided during the
				  concept plan review phase;
(b)
				  Final site layout, exact impervious area locations and acreages, proposed
				  topography, delineated drainage areas at all points of discharge from the site,
				  and stormwater volume computations for ESD practices and quantity control
				  structures;
(c) 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 ESD and erosion and sediment
				  control practices to be used;
(d) A
				  narrative that supports the site development design, describes how ESD will be
				  used to meet the minimum control requirements, and justifies any proposed
				  structural stormwater management measure; and
(e) Any other information required by the
				  approving Agency.
(4)
				  Following site development approval by the appropriate authority, 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:
(a) Final erosion and sediment control plans
				  shall be submitted according to COMAR
				  26.17.01.05 a; and
(b) 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.
(5) Reports submitted for final stormwater
				  management plan approval shall include, but are not limited to:
(a) Geotechnical investigations including
				  soil maps, borings, site-specific recommendations, and any additional
				  information necessary for the final stormwater management design;
(b) Drainage area maps depicting
				  predevelopment and postdevelopment runoff flow path segmentation and land
				  use;
(c) Hydrologic computations of
				  the applicable ESD and unified sizing criteria according to the Design Manual
				  for all points of discharge from the site;
(d) Hydraulic and structural computations for
				  all ESD practices and structural stormwater management measures to be
				  used;
(e) A narrative that supports
				  the final stormwater management design; and
(f) Any other information required by the
				  approving agency.
(6)
				  Construction drawings submitted for final stormwater management plan approval
				  shall include, but are not limited to:
(a) A
				  vicinity map;
(b) Existing and
				  proposed topography and proposed drainage areas, including areas necessary to
				  determine downstream analysis for the proposed stormwater management
				  facilities;
(c) Any proposed
				  improvements including the location of buildings or other structures,
				  impervious surfaces, storm drainage facilities, and all grading;
(d) The location of existing and proposed
				  structures;
(e) Any easements and
				  rights-of-way;
(f) The delineation,
				  if applicable, of the 100-year floodplain and any on-site wetlands;
(g) Structural and construction details
				  including representative cross sections for all components of the proposed
				  drainage system or systems and stormwater management facilities;
(h) All necessary construction
				  specifications;
(i) A sequence of
				  construction;
(j) Data for total
				  site area, disturbed area, new impervious area, and total impervious
				  area;
(k) A table showing the ESD
				  and unified sizing criteria volumes required in the Design Manual;
(l) A table of materials to be used for
				  stormwater management facility planting;
(m) All soil boring logs and
				  locations;
(n) An inspection and
				  maintenance schedule;
(o)
				  Certification by the owner/developer that all stormwater management
				  construction will be done according to this plan;
(p) An as-built certification signature block
				  to be executed after project completion; and
(q) Any other information required by the
				  approving agency.