For the purpose of this chapter, the following definitions describe
the meaning of the terms used in this chapter:
ADMINISTRATION
The Maryland Department of the Environment (MDE), Water Management
Administration.
ADVERSE IMPACT
For purposes of stormwater management, any deleterious effect
on waters or wetlands, including their quality, quantity, surface
area, species, 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
Those methods and procedures used in the cultivation of land
in order to further crops or livestock production and conservation
of related soil and water resources. Logging and timber removal operations
shall not be considered a part of this definition.
APPLICANT
Any person, firm, or government 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 Town of Galena or the agency, department, person or firm
designated by the Town to administer and enforce the provisions of
this chapter.
AQUIFER
A porous water-bearing geologic formation generally restricted
to materials 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
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/or brush from the land but which
shall not include the ordinary mowing of grass.
CONCEPT PLAN
For stormwater management purposes: the first of three plan
approvals that includes information necessary to allow an initial
evaluation of a proposed project
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
that 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.
DIRECT DISCHARGE
The concentrated release of stormwater to tidal waters or
vegetated tidal wetlands from new development or redevelopment projects
in the Chesapeake Bay 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 a property owner of the right to
use an identifiable piece of land or right for a specified purpose
or purposes, and which must be included in the conveyance of land
affected by such easement.
ENVIRONMENTAL SITE DESIGN (ESD)
Using small-scale stormwater management practices, nonstructural
techniques, and site planning to mimic natural hydrologic runoff characteristics
and minimize the impact of land development on water resources. Methods
for designing practices are specified in the Design Manual.
EXEMPTION
Those land development activities that are not subject to
the stormwater management requirements contained in this chapter.
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 BMPs are specified in the Design Manual.
EXTREME FLOOD VOLUME
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 plan approvals that includes the information
necessary to allow all approvals and permits relating to stormwater
management 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 SURFACE
Any surface that does not allow stormwater to infiltrate
into the ground.
INFILTRATION
The passage or movement of water into the soil surface.
MAXIMUM EXTENT PRACTICABLE (MEP)
Designing stormwater management systems so that all reasonable
opportunities for using ESD planning techniques and treatment practices
are exhausted and only where absolutely necessary a structural BMP
is implemented.
OVERBANK FLOOD PROTECTION VOLUME
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.
PERSON
The federal government, the state, any county, municipal
corporation, or other political subdivision of the state, or any of
their units, or an individual receiver, trustee, guardian, executor,
administrator, fiduciary, or representative of any kind or any partnership,
firm, association, public or private corporation or any other entity.
PLANNING TECHNIQUES
For stormwater management purposes: a combination of strategies
employed early in the project design to reduce the impact from development
and to incorporate natural features into a stormwater management plan.
RECHARGE VOLUME
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 exceeding 5,000
square feet of land disturbance performed on sites where existing
land use is commercial, industrial, institutional, or multifamily
residential and existing site impervious area exceeds 40%.
RETENTION STRUCTURE
A permanent structure that provides for the storage of runoff
by means of a permanent pool of water.
RETROFITTING
The implementation of ESD practices, the construction of
a structural BMP or the modification of an existing structural BMP
in a previously developed area to improve water quality over current
conditions.
SEDIMENT
Soils or other surficial materials transported or deposited
by the action of wind, water, or artificial means.
SITE
Any tract, lot, or parcel of land or combination of tracts,
lots, or parcels of land which are under one ownership or are contiguous
and in diverse ownership where development is to be performed as a
part of a unit, subdivision, or project.
SITE DEVELOPMENT PLAN
The second of three 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
Water that originates from a precipitation event.
STORMWATER MANAGEMENT SYSTEM
Natural areas, ESD 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 chapter.
WAIVER
The reduction of stormwater management requirements by Galena
for a specific development on a case-by-case review basis.
WATER QUALITY VOLUME
The volume needed to capture and treat 90% of the average
annual rainfall events at a development site. Methods for calculating
the water quality volume are specified in the Design Manual.
WATERCOURSE and/or DRAINAGEWAY
Any natural or artificial watercourse (including but not
limited to streams, rivers, creeks, ditches, channels, canals, conduits,
culverts, drains, waterways, gullies, ravines, or washes) in which
waters flow in a definite direction or course, either continuously
or intermittently; and including any area adjacent thereto which is
subject to inundation by reason of overflow or floodwaters.
WATERSHED
The total drainage area contributing runoff to a single point.