§ 17.10.050. Definitions.

For the purpose of this chapter, the following terms shall have the definitions indicated:

A.

"Administration" means the Maryland Department of the Environment (MDE) Water Management Administration (WMA).

B.

"Adverse impact" means 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.

C.

"Agricultural land management practices" means those methods and procedures used in the cultivation of land in order to further crop and livestock production and conservation of related soil and water resources.

D.

"Applicant" means any person, firm, or governmental agency that executes the necessary forms to procure official approval of a project or of a permit to carry out construction of a project.

E.

"Approving agency" means the entity responsible for the review and approval of stormwater management plans.

F.

"Aquifer" means a porous water bearing geologic formation generally restricted to materials capable of yielding an appreciable supply of water.

G.

"Best management practices" (BMP) means a structural or nonstructural practice designed to temporarily store or treat stormwater runoff in order to mitigate flooding, reduce pollution, and provide other amenities.

H.

"Channel protection storage volume (CPV)" means 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 & II.

I.

"Clearing" means the removal of trees and brush from the land but shall not include the ordinary mowing of grass.

J.

"Design manual" means the 2000 Maryland Stormwater Design Manual Volumes I & II (Maryland Department of the Environment, April 2000), and all subsequent revisions, that serves as the official guide for stormwater management principles, methods, and practices.

K.

"Detention structure" means a permanent structure for the temporary storage of runoff, which is designed so as not to create a permanent pool of water.

L.

"Develop land" means to change the runoff characteristics of a parcel of land in conjunction with residential, commercial, industrial, or institutional construction or alteration.

M.

"Direct discharge" means the concentrated release of stormwater to tidal waters or vegetated tidal wetlands from new development or redevelopment projects in the Critical Area.

N.

"Drainage area" means that area contributing runoff to a single point measured in a horizontal plane, which is enclosed by a ridgeline.

O.

"Easement" means 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.

P.

"Environmental site design (ESD)" means using 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 ESD practices are specified in the Design Manual.

Q.

"Exemption" means those land development activities that are not subject to the stormwater management requirements contained in this chapter.

R.

"Extended detention" means 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 BMP's are specified in the Design Manual.

S.

"Extreme flood volume (Qf)" means the storage volume required controlling those infrequent but large storm events in which overbank flows reach or exceed the boundaries of the one hundred-year floodplain.

T.

"Final stormwater management plan" means the last of three required plan approvals that includes all required information to allow all approvals and permits to be issued by the approving agency.

U.

"Flow attenuation" means prolonging the flow time of runoff to reduce the peak discharge.

V.

"Grading," means any act by which soil is cleared, stripped, stockpiled, excavated, scarified, filled or any combination thereof.

W.

"Impervious area" means any surface that does not allow stormwater to infiltrate into the ground.

X.

"Infiltration" means the passage or movement of water into the soil surface.

Y.

"Maximum extent practicable (MEP)" means 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.

Z.

"Modification" means the change to the minimum stormwater management requirements for specific circumstances granted by the Director of Public Works based upon a showing by the applicant that strict adherence to the requirements would result in an unreasonable necessary hardship and not fulfill the intent of this chapter.

AA.

"New development" means any construction, alteration, or improvement exceeding five thousand square feet of land disturbance performed on sites where existing land use is rural, agricultural or single family residential or any site with impervious coverage of less than forty percent imperviousness.

BB.

"Off-site stormwater management" means the design and construction of a stormwater management facility necessary to control stormwater from more than one development.

CC.

"On-site stormwater water management" means the design and construction of facilities necessary to control stormwater within a site.

DD.

"Overbank flood protection volume (Qp)" means 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.

EE.

"Person" means 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.

FF.

"Planning techniques" means a combination of strategies employed early in project design to reduce the impact from development and to incorporate nature features into a stormwater management plan.

GG.

"Recharge volume (Rev)" means 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.

HH.

"Redevelopment" means any construction, alteration, or improvement exceeding five thousand square feet of land disturbance performed on sites where existing land use is commercial, industrial, institutional, multifamily residential and existing site impervious area exceeds forty percent.

II.

"Regional stormwater management facility" means a stormwater management facility intended to control stormwater runoff from several separately owned parcels or developments within a watershed. "Regional stormwater management facility" does not include multi-lot stormwater management facilities, subdivision facilities or other stormwater management facilities constructed in connection with development or redevelopment, whether concurrently or in phases, of a site, or contiguous sites, by a single owner or a single owner's successor in title.

JJ.

"Retention structure" means a permanent structure that provides for the storage of runoff by means of a permanent pool of water.

KK.

"Retrofitting" means the implementation of ESD practices, the construction of a structural BMP in a previously developed area, the modification of an existing structural BMP, or the implementation of a nonstructural practice to improve water quality over current conditions.

LL.

"Sediment" means soils or other surficial materials transported or deposited by the action of wind, water, ice, or gravity as a product of erosion.

MM.

"Site" means any tract, lot, or parcel of land, or combination of tracts, lots, parcels of land that are in one ownership, or are contiguous and in diverse ownership, where development is to be performed as part of a unity, subdivision, or project.

NN.

"Site development plan" means the second of three required plan approvals that includes the information necessary to allow a detailed evaluation of a proposed project.

OO.

"Stabilization" means the prevention of soil movement by any of various vegetative and/or structural means.

PP.

"Stormwater" means water that originates from a precipitation event.

QQ.

"Stormwater management system" means natural areas, ESD practices, stormwater management measures, and any other structure through which stormwater flows, infiltrates, or discharges from a site.

RR.

"Stripping" means any activity that removes the vegetative surface cover including tree removal, clearing, grubbing and storage or removal of topsoil.

SS.

"Waiver" means the relinquishment from stormwater management requirements by the Director of Public Works for a specific development on a case-by-case review basis.

1.

"Qualitative stormwater management waiver" means a reduction of water quality volume and recharge volume parameters.

2.

"Quantitative stormwater management waiver" means a reduction of channel protection storage volume, overbank flood protection volume, and extreme flood volume design parameter.

TT.

"Watercourse" means 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 flood water.

UU.

"Watershed" means the total drainage area contributing runoff to a single point.

VV.

"Water quality volume (WQv)" means 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.

(Ord. O-10-02 § 1 (part))

(Ord. No. O-59-09, § I, 12-21-2009; Ord. No. O-12-16 Amended, § I, 5-23-2016)