Baltimore City Code, Article 7, § 21-1 Definitions.
§ 21-1. Definitions.
(a) In general.
In this Division II, the following terms have the meaning indicated.
(b) Adverse impact.
“Adverse impact” means any effect on waters or wetlands, including their quality, quantity, surface area, species composition, aesthetics, or usefulness for human or natural uses, that:
(1) is deleterious; and
(2) either:
(i) is or potentially can be harmful or injurious to human health, welfare, or safety, to property, or to biological productivity, diversity, or stability; or
(ii) unreasonably interferes with the enjoyment of life or property, including outdoor recreation.
(b-1) Approval.
(1) In general.
“Approval” means a documented action by the Department following a comprehensive review to determine and acknowledge that submitted materials demonstrate compliance with the requirements of a specified stage in a project’s process.
(2) Exclusions.
“Approval” does not include an acknowledgment by the Department that material has been received for review.
(c) Best management practice .
“Best management practice” means a structural or nonstructural practice designed to store temporarily or treat stormwater runoff in order to mitigate flooding, reduce pollution, and provide other amenities.
(d) Channel protection storage volume.
“Channel protection storage volume” means the volume, calculated in accordance with the State’s Design Manual, used to design structural management practices to control stream channel erosion.
(e) Department.
“Department” means the Baltimore City Department of Public Works.
(e-1) Design Guidelines, City.
“Design Guidelines, City” means the 2010 Baltimore City Stormwater Design Guidelines, and all subsequent additions, revisions, and amendments to it, as adopted by the Department and approved by the State Water Management Administration.
(f) Design Manual.
“Design Manual, State” means the 2000 Maryland Stormwater Design Manual and all subsequent additions, revisions, and amendments to it.
(g) Develop.
“Develop” means to change the runoff characteristics of a parcel of land in conjunction with residential, commercial, industrial, or institutional construction or alteration.
(h) Disturb.
(1) “Disturb” means to:
(i) clear or remove trees and brush from land;
(ii) grade, stockpile, remove, excavate, scarify, or fill soil;
(iii) grub or remove stumps; or
(iv) strip or remove vegetative surface cover.
(2) “Disturb” does not include:
(i) mowing of grass;
(ii) trimming of trees; or
(iii) other maintenance activities that do not create unvegetated ground.
(i) Drainage area.
“Drainage area” means an area, measured in a horizontal plane, that:
(1) contributes runoff to a single point; and
(2) is enclosed by a ridge line.
(i-1) Environmental site design.
“Environmental site design” means using small-scale stormwater management practices, nonstructural techniques, and better site planning that, in accordance with methods specified in the State’s Design Manual, are used to mimic natural hydrologic runoff characteristics and minimize the impact of land development on water resources.
(j) Extreme flood volume.
“Extreme flood volume” means the storage volume required to control infrequent, large storm events in which overbank flows reach or exceed the boundaries of the 100- year floodplain.
(j-1) Impervious area.
“Impervious area” means any surface that does not allow stormwater to infiltrate into the soil surface.
(k) {Repealed}
(l) Infiltration.
“Infiltration” means the passage or movement of water into the soil surface.
(l-1) Maximum extent practicable.
“Maximum extent practicable” means stormwater management systems designed so that:
(1) all reasonable opportunities for using environmental site design planning techniques and treatment practices are exhausted; and
(2) a structural best management practice is implemented only where absolutely necessary.
(m) Off-site ... management.
“Off-site ... management” means the design and construction of a facility necessary to control stormwater from more than one development.
(n) On-site ... management.
“On-site ... management” means the design and construction of systems necessary to control stormwater within one development.
(o) Overbank flood protection volume.
“Overbank flood protection volume” means the volume, calculated in accordance with the State’s Design Manual, controlled by structural practices to prevent an increase in the frequency of out of bank flooding generated by development.
(p) Person.
(1) In general.
“Person” has the meaning stated in § 1-107(a) {“Person: In general”} of the City Code’s General Provisions Article.
(2) Qualified inclusion of governmental entities.
Notwithstanding § 1-107(b) {“Person: Exclusion”} of the General Provisions Article, in this Division II “person” also includes, except as used in § 28-13{“Criminal penalties”}, a governmental entity or an instrumentality or unit of a governmental entity.
(p-1) Planning techniques.
“Planning techniques” means 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.
(q) Qualitative Control.
See “Stormwater management – Qualitative control”.
(r) Quantitative Control.
See “Stormwater management – Quantitative control”.
(s) Recharge volume.
“Recharge volume” means that portion of the water quality volume, calculated in accordance with the State’s Design Manual, used to maintain groundwater recharge rates at development sites.
(t) Redevelopment.
“Redevelopment” means any construction, alteration, or improvement that:
(1) disturbs more than 5,000 square feet of land;
(2) is performed on a site where:
(i) the existing land use is commercial, industrial, institutional, or multi-family residential; and
(ii) the existing impervious area of the site is more than 40% of the total area of the site.
(t-1) Retrofitting.
“Retrofitting” means the implementation of environmental site design practices, the construction of a structural best management practice, or the modification of an existing structural best management practice in a previously developed area to improve water quality over current conditions.
(u) Sediment.
“Sediment” means soils or other surficial materials that are the product of erosion and are transported or deposited by the action of wind, water, ice, gravity, or artificial means.
(v) Site.
“Site” means any tract, lot, parcel of land, or area of construction, or combination of tracts, lots, parcels of land, or areas of construction that are:
(1) in one ownership; or
(2) in diverse ownership, but where:
(i) development is to be performed as part of a unit, subdivision, or project; and
(ii) either:
A. the tracts, lots, or parcels of land are contiguous; or
B. the development is a cooperative public-private undertaking.
(w) Stabilization.
“Stabilization” means the prevention of soil movement by any of various vegetative or structural means.
(w-1) Stormwater.
“Stormwater” means water that originates from a precipitation event.
(w-2) Stormwater management system.
“Stormwater management system” means a system of natural areas, environmental site design practices, stormwater management practices, and any structure through which stormwater flows, infiltrates, or discharges from a site.
(x) Stormwater management – Qualitative control.
(1) In general.
“Stormwater management” means, for qualitative control, a system of vegetative, structural, and nonstructural practices, natural areas, environmental site design practices, stormwater management measures, and any other structure that reduces or eliminates pollutants that might otherwise be carried by surface runoff.
(2) Inclusions.
“Stormwater management” includes, for qualitative control, design parameters for:
(i) water quality volume; and
(ii) recharge volume.
(y) Stormwater management – Quantitative control.
(1) In general.
“Stormwater management” means, for quantitative control, a system of vegetative, structural, and nonstructural practices, natural areas, environmental site design practices, stormwater management measures, and any other structure that controls the increased volume and rate of surface runoff caused by man-made changes to the land.
(2) Inclusions.
“Stormwater management” includes, for quantitative controls, design parameters for:
(i) channel protection storage volume;
(ii) overbank flood protection volume; and
(iii) extreme flood volume.
(z) {Vacant}
(aa) Watershed.
“Watershed” means the total drainage area contributing runoff to a single point.
(bb) Water quality volume.
“Water quality volume” means the volume needed, calculated in accordance with the State’s Design Manual, to capture and treat the runoff from 90% of the average annual rainfall at a development site.
(cc) Wetlands.
“Wetlands” means an area that has saturated soils or periodic high groundwater levels and vegetation adapted to wet conditions and periodic flooding.
(Ord. 22-125; Ord. 13- 095; Ord. 10-277; Ord. 04-672; Ord. 02-367.)