Definitions of words and phrases. For
the purposes of this Title, the following definitions shall apply:
ADMINISTRATION
The Maryland Department of the Environment (MDE) Water Management
Administration.
ADVERSE IMPACT
Any deleterious effect on waters or wetlands, including their
quality, quantity, surface area, species composition, aesthetics or
usefulness for human or natural uses which are or may potentially
be harmful or injurious to human health, welfare, safety or property,
to biological productivity, diversity, or stability or which unreasonably
interfere with the enjoyment of life or property, including outdoor
recreation.
AGRICULTURAL LAND MANAGEMENT PRACTICES
Those methods and procedures used in the cultivation of land
in order to further crop and livestock production and the conservation
of related soil and water resources.
APPLICANT
Any person, firm or governmental agency who executes the
necessary forms to procure official approval of a project or a permit
to carry out construction of a project.
APPROVING AGENCY
The entity responsible for the review and approval of stormwater
management plans.
AQUIFER
A porous water-bearing geologic formation generally restricted
to materials capable of yielding an appreciable supply of water.
BEST MANAGEMENT PRACTICE (BMP)
A structural device or nonstructural practice designed to
temporarily store or treat stormwater runoff in order to mitigate
flooding, reduce pollution, and provide other amenities.
CHANNEL PROTECTION STORAGE VOLUME (Cpv)
The volume used to design structural management practices
to control stream channel erosion. Methods for calculating the channel
protection storage volume are specified in the 2000 Maryland Stormwater
Design Manual, Volumes I and II.
CLEARING
The removal of trees and brush from the land, but not including
the ordinary mowing of grass.
CONCEPT PLAN
The first of three required plan approvals that includes
the information necessary to allow an initial evaluation of a proposed
project.
DEPARTMENT
The County department designated by the County Commissioners
to administer and enforce this Subtitle.
DESIGN MANUAL
The 2000 Maryland Stormwater Design Manual, and all subsequent
revisions, that serves as the official guide for stormwater management
principles, methods, and practices.
DETENTION STRUCTURE
A permanent structure for the temporary storage of runoff
which is designed so as not to create a permanent pool of water.
DEVELOP LAND
To change the runoff characteristics of a parcel of land
in conjunction with residential, commercial, industrial, or institutional
construction or alteration.
DEVELOPER
Anyone involved in or authorizing any disturbance, alteration,
modification, change or transformation of land.
DIRECT DISCHARGE
The concentrated release of stormwater to tidal waters or
vegetated tidal wetlands from new development or redevelopment projects
in the Critical Area.
DRAINAGE AREA
That area contributing runoff to a single point measured
in a horizontal plane, which is enclosed by a ridge line.
EASEMENT
A grant or reservation by the owner of land for the use of
such land by others for a specific purpose or purposes, and which
must be included in the conveyance of land affected by such easement.
ENVIRONMENTAL SITE DESIGN (ESD)
The use of small-scale stormwater management practices, nonstructural
techniques, and better site planning to mimic natural hydrologic runoff
characteristics and minimize the impact of land development on water
resources. Methods for designing environmental site design practices
are specified in the Design Manual.
EXEMPTION
Those land development activities that are not subject to
the stormwater management requirements contained in this Subtitle.
EXTENDED DETENTION
A stormwater design feature that provides gradual release
of a volume of water in order to increase settling of pollutants and
protect downstream channels from frequent storm events. Methods for
designing extended detention best management practices are specified
in the Design Manual.
EXTREME FLOOD VOLUME (Qf)
The storage volume required to control those infrequent but
large storm events in which overbank flows reach or exceed the boundaries
of the one-hundred-year floodplain.
FINAL STORMWATER MANAGEMENT PLAN
The last of three required plan approvals that includes the
information necessary to allow all approvals and permits to be issued
by the approving agency.
FLOW ATTENUATION
Prolonging the flow time of runoff to reduce the peak discharge.
GRADING
Any act by which soil is cleared, stripped, stockpiled, excavated,
scarified, filled or any combination thereof.
IMPERVIOUS AREA
Any surface that does not allow stormwater to infiltrate
into the ground.
INFILTRATION
The passage or movement of water into the soil surface.
LIMITS OF DISTURBANCE (LOD)
The boundaries of that area of land to be cleared of trees
and other vegetation or otherwise disturbed or modified by any means
from its original condition in conjunction with a proposed development
or land use.
LOT OF RECORD
A plot or parcel of land delineated upon the land records
of the County as of July 27, 1965, or any validly recorded platted
lot of a subdivision or parcel of land which, at the time of its recording,
complied with all applicable laws, ordinances and regulations.
MAXIMUM EXTENT PRACTICABLE (MEP)
The design of stormwater management systems so that all reasonable
opportunities for using environmental site design planning techniques
are exhausted, with structural best management practices implemented
only where absolutely necessary.
OFF-SITE STORMWATER MANAGEMENT
The design and construction of a facility necessary to control
stormwater for a development located on a site different than that
on which the stormwater management facility itself is located.
OVERBANK FLOOD PROTECTION VOLUME (Qp)
The volume controlled by structural practices to prevent
an increase in the frequency of out-of-bank flooding generated by
development. Methods for calculating the overbank flood protection
volume are specified in the Design Manual.
OWNER
The person or persons holding actual title to the land which
may be subject to the regulations of this Subtitle.
PLANNING TECHNIQUES
A combination of strategies employed early in project design
to reduce the impact from development and to incorporate natural features
into a stormwater management plan.
RECHARGE VOLUME (Rev)
That portion of the water quality volume used to maintain
groundwater recharge rates at development sites. Methods for calculating
the recharge volume are specified in the Design Manual.
REDEVELOPMENT
Any construction, alteration, or improvement performed on
sites where existing land use is commercial, industrial, institutional,
or multifamily residential and existing site imperviousness area exceeds
forty percent, regardless of total site disturbance area.
RETENTION STRUCTURE
A permanent structure that provides for the storage of runoff
by means of a permanent pool of water.
RETROFITTING
The implementation of environmental site design practices,
the construction of a structural best management practice, or a modification
of an existing structural best management practice in a previously
developed area to improve water quality over current conditions.
REVIEWING AGENT
The agency or individual designated by the County Commissioners
to review stormwater management plans and related documentation as
required under this Subtitle.
SEDIMENT
Soils or other surficial materials transported or deposited
by the action of wind, water, ice, or gravity as a product of erosion.
SITE
(1)
For new development, any tract, lot, or parcel of land or combination
of tracts, lots, or parcels of land, which are in one ownership, or
are contiguous and in diverse ownership where development is to be
performed as part of a unit, subdivision, or project.
(2)
For redevelopment, the area of new construction as shown on
an approved site plan; or the original parcel. Final determination
of the applicable area shall be made by the Department.
SITE DEVELOPMENT PLAN
The second of three required plan approvals that includes
the information necessary to allow a detailed evaluation of a proposed
project.
STABILIZATION
The prevention of soil movement by any of various vegetative
and/or structural means.
STORMWATER
The water that originates from a precipitation event.
STORMWATER MANAGEMENT
For quantitative control, a system of vegetative and structural
measures that controls the increased volume and rate of surface runoff
caused by man-made changes to the land; and, for qualitative control,
a system of vegetative, structural, and other measures that reduces
or eliminates pollutants that might otherwise be carried by surface
runoff.
STORMWATER MANAGEMENT PLAN
A set of drawings or other documents submitted by a person
as a prerequisite to obtaining a stormwater management approval, which
contain all of the information and specifications pertaining to stormwater
management.
STORMWATER MANAGEMENT SYSTEM
The natural areas, environmental site design practices, stormwater
management measures, and any other structure through which stormwater
flows, infiltrates, or discharges from a site.
STRIPPING
Any activity which removes the vegetative surface cover,
including tree removal, clearing, grubbing and storage or removal
of topsoil.
VARIANCE
The modification of the minimum stormwater management requirements
for specific circumstances such that strict adherence to the requirements
would result in unnecessary hardship and not fulfill the intent of
this Subtitle.
WAIVER
The reduction of stormwater management requirements by the
Department for a specific development on a case-by-case basis. A qualitative
stormwater management waiver includes water quality volume and recharge
volume design parameters. A quantitative stormwater management waiver
includes channel protection storage volume, overbank flood protection
volume, and extreme flood volume design parameters.
WATERCOURSE
Any natural or artificial stream, river, creek, ditch, channel,
canal, conduit, culvert, drain, waterway, gully, ravine or wash, in
and including any adjacent area that is subject to inundation from
overflow or floodwater.
WATERSHED
The total drainage area contributing runoff to a single point.
WATER QUALITY VOLUME (WQv)
The volume needed to capture and treat the runoff from ninety
percent of the average annual rainfall at a development site. Methods
for calculating the water quality volume are specified in the Design
Manual.
WETLANDS, NONTIDAL
An area that is inundated or saturated by surface water or
groundwater at a frequency and duration sufficient to support, and
that under normal circumstances does support, a prevalence of vegetation
typically adapted for life in saturated soil conditions, commonly
known as "hydrophytic vegetation." Nontidal wetlands are identified
by the most recent federal definition and guidelines for identifying
and delineating jurisdictional wetlands.
WETLANDS, PRIVATE
Any land not considered state wetlands bordering on or lying
beneath tidal waters, which is subject to regular or periodic tidal
action and supports aquatic growth. This includes wetlands, transferred
by the state by a valid grant, lease, patent or grant confirmed by
Article 5 of the Declaration of Rights of the Constitution, to the
extent of the interest transferred.
WETLANDS, STATE
Any land under the navigable waters of the state below the
mean high tide, affected by the regular rise and fall of the tide.
Wetlands of this category which have been transferred by the state
by valid grant, lease, patent or grant confirmed by Article 5 of the
Declaration of Rights of the Constitution shall be considered private
wetlands to the extent of the interest transferred.
WETLANDS, TIDAL
"Tidal wetlands" shall include all private and state wetlands
as defined herein.