Section 12A-5 Definitions.
Prior to the adoption of Ord. 19442 on 03/05/2007, Section 12A-5 read as follows.
For the purposes of this chapter, the following words and
phrases shall have the meaning given
Agricultural activity. Normal farming operations including improvements
conducted under the
auspices of the
Natural Resource Conservation Service
Best management practices (BMP). Activities, practices
and procedures which control soil loss
and reduce or prevent water quality degradation caused by nutrients, animal wastes, toxins,
organics and sediment in the runoff. BMPs may either be structural (grass swales, terraces,
retention and detention ponds, and others); or nonstructural (disconnection of impervious
surfaces, directing downspouts onto grass surfaces and educational activities).
Central business district. The area bounded by
College Avenue on the east, Elm Street and
Elm Street extended on the south, Garth Avenue on the west, and Park Avenue and Park Avenue
extended on the north.
City utility service customer. A purchaser of city water, electric, sewage or refuse collection
Clean fill. Uncontaminated soil, rock, sand, gravel, concrete, asphaltic concrete, cinder-blocks,
brick, minimal amounts of wood and metal, and inert solids which are approved by rule or policy
of the State Department of Natural Resources for fill, reclamation or other beneficial use.
Clear cutting. The practice of removing over half of the standing
climax forest area
on a site.
Climax forest. Any woodland community of over twenty thousand (20,000) square feet which
is dominated by climax species such as oak, hickory, sugar maple or bottomland hardwoods such
as river birch, basswood, sycamore and hornbeam and which includes an area of five thousand
(5,000) square feet with a maximum aspect ratio of 4:1.
Critical downstream location. A location within the drainage reach downstream of the subject
site, consisting of a channel section, drainage swale, bridge, box culvert, storm sewer, or other
conveyance facility or structure having a conveyance capacity which would be exceeded by
storm water runoff from a 10-year frequency, 24-hour duration storm under existing land use
conditions; or an existing structure or building located downstream of the subject site which has
its lowest floor elevation less than one (1) foot above the maximum elevation in an adjacent
channel attained by the 100-year frequency, 24-hour duration storm, assuming existing land use
conditions with the proposed ultimate development of the subject site in place. The conveyance
capacity of a structure operating under inlet control conditions shall be determined with a
maximum headwater to diameter ration (HW/D) of 1.25 or with a headwater elevation equal to
the top of curb, whichever is less.
dbh (diameter breast height). Trunk diameter at 4.5 feet about ground.
Design year storm. The selected or established frequency or return period of rainfall time-duration
for which drainage facilities are to be designed.
Developed land. Real estate altered by the addition of impervious surface which changes the
hydrology of the property from its natural state.
Developer. A person whose intent or function is to bring about any change of land use or
improvement on any parcel of land.
Any change of land use or improvement on any parcel
1) The improvement of property for any purpose involving construction; 2) the preparation of
land for construction; or, 3) land disturbance that requires the issuance of a land disturbance
Director. The director of public works or
Drainage basin (or watershed). The catchment area from which storm water is carried off by a
watercourse or storm drainage system. The area served by a drainage system receiving storm and
other surface-borne water. Drainage basin boundaries are a product of natural topography and
drainage system configuration.
Drainage facility. A man-made structure or natural watercourse for the conveyance of storm
runoff. Examples are channels, pipes, ditches, swales, catch basins, and street gutters.
Dwelling unit. A building or portion thereof, designed to house a family.
Forest land. Forested land area with the aerial canopy dominated by trees greater than
inches in diameter, measured four and one-half (4 1/2) feet above the ground.
Forest parcel. An envelope of trees delineated by the boundaries of grading limits or land
Impervious surface. A surface on real property where infiltration of storm water into the earth
has been virtually eliminated by the works of man. Impervious surfaces shall include, but not be
limited to: Roofs, paved driveways, patio areas, sidewalks, parking lots, storage areas, and other
oil or macadam surfaced areas which prevent percolation of storm waters into the earth's surface.
Infiltration. The process of percolating stormwater into the
Land disturbance. Any activity, including mechanized clearing, which removes the vegetative
Land disturbance permit. A permit issued by the City of Columbia
that authorizes the
commencement of land disturbance activities
Logging. The removal of more than three (3) existing trees for commercial purposes on any
tract of land larger than one (1) acre.
Main floor area. The area within the perimeter of the exterior walls of a building excluding
any attached garage. The main floor area does not include the area of decks, porches, patios or
Maximum aspect ratio of 4:1. A means of defining the configuration of an area of trees such
that the measurement of length of the area shall not be more than four (4) times as long as the
measurement of width of the area.
Mechanized clearing. Clearing of land by tracked or wheeled vehicles which scrape, cultivate
or scarify the surface of the ground exposing bare soil and uprooting vegetation.
Multiple-family building. A building with more than one dwelling unit.
Non-point source pollution. Pollution which is generated by
various land use activities rather
than from an identifiable or discrete source, and which is conveyed to waterways through natural
processes, such as rainfall, stormwater runoff, or ground water seepage and infiltration rather
than through direct discharge.
Nonresidential use. The use of developed land for any purpose other than for a single-family
residence or a multiple-family building.
Occupant. The person in possession or lawfully entitled to possession of a parcel of land.
Owner. Any person having legal title to, or a proprietary interest in real property. Proprietary
shall include, but not be limited to, estate administration, trusteeship, guardianship, and actions
under a valid power of attorney.
Peak runoff. The maximum rate at which storm water travels across the surface of the ground.
Pollutant. Anything which causes or contributes
to pollution. Pollutants may include, but are
not limited to: paints, varnishes, and solvents; oil and other automotive fluids; non-hazardous
liquid and solid wastes, yard wastes; refuse, rubbish, garbage, litter, or other discarded or
abandoned objects, articles, and accumulations, which may cause or contribute to pollution;
floatables; pesticides, herbicides, and fertilizers; hazardous substances and wastes; sewage, fecal
coliform and pathogens; dissolved and particulate metals; animal wastes; wastes and residues
that result from constructing a building or structure; including but not limited to sediments,
slurries and concrete rinsate and noxious or offensive matter of any kind.
Redevelopment. Any reconstruction, rehabilitation, addition
or other improvement of a
property (exclusive of R-1 and R-2 zoned properties) the cost of which equals or exceeds fifty
percent (50%) of the market value of the structure before the start of construction of the
Site. The total area of the parcel, tract, lot or ownership of land upon which development or
land disturbance is proposed irrespective of the actual limits or size of the proposed development
or land disturbance activity.
Storm drain. A closed conduit or open ditch, natural or specifically constructed, for
conducting or conveying collected storm water. Conduits and paved open ditches are termed
"improved"; unpaved ditches are termed "unimproved".
Storm drainage design manual. A City manual intended primarily for use by land developers
in the design of minor storm drainage systems, such as a storm drains, relatively small culverts,
associated streets and gutter flow hydraulics, natural drainage swales, storm inlets and detention
facilities. The manual includes drainage policy to be followed, standard design methods,
computation forms, and City standards.
Storm drainage system. All drainage facilities used for collecting and conducting storm water
to, through and from drainage areas to the points of final outlet including, but not limited to, the
following: Conduits and appurtenant features, canals, ditches, streams, gullies, flumes, culverts,
streets, gutters, and pump stations.
Stormwater: Any surface flow, runoff, and drainage consisting
entirely of water from any form
of natural precipitation, and resulting from such precipitation including snowmelt.
Stormwater management facilities. This term includes measures,
primarily structural, which
are determined to be the most effective, practical means of preventing or reducing point source or
non-point source pollution inputs to stormwater runoff and subsequently into water bodies. These
facilities are also used to control volume and peak rates of runoff from development and
Stream channel. A naturally or artificially created water course
with definite bed and banks
which conducts continuously or periodically flowing water.
Swale. A wide shallow ditch used to carry storm runoff.
Total suspended solids. Matter suspended in stormwater excluding
litter, debris, and other
gross solids exceeding one (1) millimeter in diameter.
Tree. Any self-supporting woody perennial plant, usually with one (1) main stem or trunk.
Tree, existing. A tree which meets or exceeds the following size standards: Deciduous shade
trees shall have a four (4) inch
, measured four and one-half (4 1/2) feet above the
ground and ornamental and evergreen species shall be a minimum of six (6) feet in height.
Unimproved land. Land or property having little or no "impervious surface."
Water quality volume. The storage needed to capture and treat
ninety percent (90%) of an
average annual stormwater runoff volume. It is calculated by multiplying the water quality storm
times the volumetric runoff coefficient and site area.
Watercourse. A stream, usually flowing in a particular direction (though it need not flow
continuously in a definite channel), having a bed or banks and usually discharging into some
other stream or body of water.
A drainage basin.
All the land area which drains to a given body of water.
(Ord. No. 13019, § 1, 7-1-91; Ord. 13374, § 1, 7-20-92; Ord. No. 13590
§ 1, 2-15-93; Ord. No.
14389 § 1, 3-6-95; Ord. No. 018164, § 1, 7-19-04)