§ 26-152. Definitions.

Unless specifically defined in this section, words or phrases used in this chapter shall be interpreted so as to give them the meaning they have in common usage, and to give this article the most reasonable application.

100-year flood elevation means the elevation of the 100-year flood at any given location.

500-year flood elevation means the elevation of the 500-year flood at any given location

1-year frequency storm means a storm event defined to be two and one-half inches in 24 hours or other such magnitude the director shall establish based upon scientific and engineering information.

2-year frequency storm means a storm event with a 50 percent chance of being equaled or exceeded in a given year. Defined to be 3.3 inches in 24 hours or other such magnitude the director shall establish based upon scientific and engineering information.

5-year frequency storm means a storm event with a 20 percent chance of being equaled or exceeded in any given year. Defined to be 4.1 inches in 24 hours or other such magnitude the director shall establish based upon scientific and engineering information.

10-year frequency storm means a storm event with a ten percent chance of being equaled or exceeded in any given year. Defined to be 4.8 inches in 24 hours or other such magnitude the director shall establish based upon scientific and engineering information.

25-year frequency storm means a storm event with a four percent chance of being equaled or exceeded in any given year. Defined to be five and one-half inches in 24 hours or other such magnitude the director shall establish based upon scientific and engineering information.

100-year frequency storm means a storm event with a one percent chance of being equaled or exceeded in any given year. Defined to be six and one-half inches in 24 hours or other such magnitude the director shall establish based upon scientific and engineering information.

500-year frequency storm means a storm event with a one-fifth of one percent chance of being equaled or exceeded in any given year. Defined to be 7.6 inches in 24 hours or other such magnitude the Director shall establish based upon scientific and engineering information.

Active channel means the area of the stream that is most subject to water flow and that includes the portion of the channel below the top-of-bank.

Aquatic Resource Alteration Permit (ARAP) means a permit issued by the Tennessee Department of Environment and Conservation for physically altering Waters (streams and wetlands) of the state.

As-built certification means as-built, field-verified plans signed and sealed by a registered professional engineer and/or a registered land surveyor, both licensed to practice in the state, which shows physical information about the development or redevelopment for purposes of verifying adherence to the approved stormwater management plan(s).

Base flood elevation (BFE) the 500-year flood elevation at any given location.

Best management practices (BMP or BMPs) schedules of activities, prohibitions of practices, maintenance procedures, structural controls and other management practices designed to prevent or reduce the pollution of waters of the United States. BMPs may include structural devices or non-structural practices.

Blue-line stream means any stream that is shown on a 7.5 minute USGS quadrangle map, unless determined otherwise by the Tennessee Department of Environment and Conservation.

Board of zoning appeals (BZA) means a group of nine citizens appointed by the County Commission to hear appeals and decide appeals and variances as authorized in section 6.60 of the county zoning ordinance.

CFR means Code of Federal Regulations.

Channel means a natural or man-made watercourse of perceptible extent, with definite bed and banks to confine and conduct continuously or periodically flowing water.

Clearing means in the definition of discharges associated with construction activity, clearing does not refer to clearing of vegetation along roadways, highways or power lines for sight distance or other maintenance and/or safety concerns, or cold planing, milling, and/or removal of concrete and/or bituminous asphalt roadway pavement surfaces. Clearing typically refers to removal of vegetation and/or disturbance of soil prior to grading or excavation in anticipation of construction activities. Clearing may also refer to wide area land disturbance in anticipation of non-construction activities; for instance, cleared forested land in order to convert forest land to pasture for wildlife management purposes.

Commencement of construction or commencement of land disturbing activities means the initial disturbance of soils associated with clearing, grading or excavating activities or other construction activities.

Community waters means any of the following waterbodies located within the unincorporated areas of the county are considered community waters:

(1)

Streams, as defined herein;

(2)

Wetlands, as defined by the any agency with authority to make legal wetland determinations (United States Army Corps of Engineers, United States Environmental Protection Agency, Tennessee Department of Environment and Conservation, United States Natural Resources Conservation Service);

(3)

Ponds that have a direct hydraulic connection to other community waters; and

(4)

Lakes.

Construction means any placement, assembly, or installation of facilities or equipment (including contractual obligations to purchase such facilities or equipment) at the premises where such equipment will be used, including preparation work at such premises.

Construction related wastes means refuse or unused materials that can result from construction activities. Construction related wastes can include, but are not limited to, unused building and landscaping materials, chemicals, litter, sanitary waste, and concrete truck washout.

Conveyance means the capacity of a channel or a pipe to carry stormwater.

Covenants for permanent maintenance of stormwater facilities and best management practices means a legal document executed by the property owner, or a homeowners' association as owner of record, and recorded with the county register of deeds which guarantees perpetual and proper maintenance of stormwater facilities and best management practices.

County means Knox County, Tennessee.

Cross drain means a pipe used to convey stormwater from one side of a county road to another. A cross drain can also be called a culvert.

Development means any land change that alters the hydrologic or hydraulic conditions of any property. Often referred to as "site development." Development includes, but is not limited to, providing access to a site, clearing of vegetation, grading, earth moving, providing utilities, roads and other services such as parking facilities, stormwater management and erosion control systems, potable water and wastewater systems, altering land forms, or construction or demolition of a structure on the land.

Director means the director of the county department of engineering and public works or designee.

Discharge means dispose, deposit, spill, pour, inject, seep, dump, leak or place by any means, or that which is disposed, deposited, spilled, poured, injected, seeped, dumped, leaked, or placed by any means including any direct or indirect entry of any solid or liquid matter into the stormwater system by any means intentional or otherwise.

Disturbed area means portion of any site that has been altered from existing conditions, including but not limited to the following: providing access to a site, clearing of vegetation, grading, earth moving, providing utilities and other services such as parking facilities, stormwater management and erosion control systems, potable water and wastewater systems, altering land forms, or construction or demolition of a structure on the land.

Drainage basin means the area contributing stormwater runoff to a single point.

Drainage system means the system of pipes, channels, culverts, and ditches that convey stormwater from and through public and private land in the county.

Erosion means the removal of soil particles by the action of water, wind, ice or other geological agents, whether naturally occurring or acting in conjunction with or promoted by anthropogenic activities or effects.

Excavation means a cavity or hole in the land surface that is caused by the cutting, digging, or scooping and removal of soil, rock, or other materials.

Exceptional Tennessee waters means surface waters of the State of Tennessee that satisfy characteristics of exceptional Tennessee waters as listed Chapter 1200-4-3-.06 of the official compilation - Rules and Regulations of the State of Tennessee. Characteristics include waters designated by the Water Quality Control Board as Outstanding National Resource Waters (ONRW); waters that provide habitat for ecologically significant populations of certain aquatic or semi-aquatic plants or animals; waters that provide specialized recreational opportunities; waters that possess outstanding scenic or geologic values; or waters where existing conditions are better than water quality standards.

FEMA means the Federal Emergency Management Agency, which administers the National Flood Insurance Program (NFIP).

Filling means any deposit or stockpiling of dirt, rocks, stumps, or other natural or man-made solid waste material.

Flood means water from a river, stream, watercourse, lake or other body of standing water that temporarily overflows and inundates adjacent lands and which may affect other lands and activities through increased surface water levels, and/or increased groundwater level.

Flood fringe means that portion of the special flood hazard area lying outside the floodway.

Flood insurance rate map (FIRM) means the official map on which the Federal Emergency Management Agency has delineated both the areas of special flood hazard and the risk premium zones.

Flood insurance study (FIS) means the official report provided by the Federal Emergency Management Agency. The report contains elevations of the base flood, floodway widths, flood velocities, and flood profiles.

Floodplain means any land area susceptible to being inundated by water from any source. Floodplains that have been studied for purposes of flood insurance documentation are typically assigned a recurrence interval (i.e., the 100-year floodplain) which defines the magnitude of the flood event that causes the inundation in the floodplain to a specified flood elevation. The 100-year floodplain is the area subject to inundation during the 100-year flood.

Flood proofing means any combination of structural and nonstructural additions, changes, or adjustments to structures which reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures and their contents.

Floodway means the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the 100-year flood without cumulatively increasing the water surface elevation more than one foot.

Floodway encroachment means any obstruction, fill, construction, improvement or other alteration that changes the hydraulic characteristics of the regulatory floodway.

Grading means any clearing, excavating, filling or other disturbance of terrain.

Grading permit means a permit issued by the county authorizing the commencement of land disturbing activities.

Hotspot means an area where the land use or activities generate highly contaminated runoff, with concentrations of pollutants in excess of those typically found in stormwater.

Human occupancy means any portion of any enclosed structure wherein humans principally live, work, or sleep such as mobile homes, residential activities, basements, health care facilities, restaurants, office buildings, etc.

Illicit discharge means any discharge to the stormwater system that is not composed entirely of stormwater and not specifically exempted in sections 26-312—26-316.

Impervious area means impermeable surfaces which prevent the percolation of water into the soil including, but not limited to, pavement, parking areas and driveways, packed gravel or soil, or rooftops.

Lake means an inland body of standing water, usually of considerable size.

Land disturbing activity means any activity on a property that results in a change in the existing soil (both vegetative and non-vegetative) and/or the existing soil topography. Land disturbing activities include, but are not limited to, development, re-development, demolition, construction, reconstruction, clearing, grading, filling, logging and/or tree chipping operations, haul roads associated with the development, and excavation.

Letter of map revision (LOMR) means a letter written by FEMA that officially revises the FIS and FIRM.

Municipal separate storm sewer system (MS4) means a conveyance or system of conveyances (including roads with drainage systems, streets, catch basins, curbs, gutters, ditches, constructed channels, and storm drains) designed or used for collecting or conveying stormwater. However, sanitary and combined sewers are not included in the definition of the municipal separate storm sewer system.

National pollutant discharge elimination system (NPDES) means the program administered by the United States Environmental Protection Agency to eliminate or reduce pollutant discharges to the waters of the United States.

Natural resources conservation service (NRCS) means an organization within the U.S. Department of Agriculture that has published standard drainage procedures in the form of Technical Release No. 55. Formerly known as the Soil Conservation Service (SCS).

No rise means a floodway encroachment that causes no increase to the base flood elevation, and to the 100-year floodway width and water surface elevation.

Outfall means the terminus of a stormwater system where the contents are released into a larger public or private stormwater management system, or into a stream.

Owner or operator means any party associated with a construction project that meets either of the following two criteria:

(1)

The party has operational control over construction plans and specifications, including the ability to authorize modifications to those plans and specifications (this will typically be the owner or developer); or

(2)

The party has day-to-day operational control of those activities at a project which are necessary to ensure compliance with a stormwater pollution prevention plan (SWPPP) for the site or other permit conditions, e.g., they are authorized to direct workers at a site to carry out activities required by the SWPPP or comply with other permit conditions. (This will typically include the general contractor and would also include erosion control contractors.)

Pond means an inland body of standing water that is usually smaller than a lake.

Priority construction activity means land disturbing activities that are located in a watershed that discharges to waters recognized by the state as impaired for siltation, or exceptional Tennessee waters.

Peak discharge means the maximum instantaneous rate of flow of water at a particular point resulting from a storm event. Also, the maximum discharge computed for a given design flood event.

Person means any individual, firm, corporation, partnership, association, organization or entity, including governmental entities, or any combination thereof.

Public water means stormwater runoff that originates in whole or part from or is conveyed by publicly owned facilities such as roads.

Redevelopment means the improvement of a lot or lots that have been previously developed.

Riprap means a combination of large stone, cobbles and boulders used to line channels, stabilize stream banks, and reduce runoff velocities.

Runoff means the water resulting from precipitation that is not absorbed by the soil. Also can be referred to as stormwater runoff.

Sanitary sewer means a system of underground conduits that collects and delivers wastewater from toilets, sinks and other plumbing fixtures to a wastewater treatment plant.

Sediment means solid material, either inorganic (mineral) or organic, that is in suspension, is being transported, or has been moved from the site of origin by wind, water, gravity, or ice as a product of erosion.

Sewage means human wastes carried by water from residences, buildings, industrial establishments or other places, together with such industrial wastes, stormwater or other water as may be present; or any substance discharged from a sanitary sewer collection system.

Sinkhole means a depression characterized by closed contours on a topographic map. A sinkhole throat, or opening to the subsurface, may or may not be visible. Field verification may be required in areas where the depth of the depression is below the tolerance of currently available topographic mapping. The extent of the area considered to be a sinkhole is, at a minimum, the limits determined by the sinkhole floodplain elevation, assuming plugged conditions (0 cfs outflow).

Sinkhole floodplain elevation means the elevation at the sinkhole lip or the flood elevation expected under extreme flood conditions outlined in section 26-198.

Sinkhole floodplain storage volume means the storage volume below the sinkhole floodplain elevation.

Sinkhole lip elevation means the elevation of the highest closed contour around a sinkhole. If the flood elevation is above the sinkhole lip, water will flow away from the sinkhole.

Small lot, for purposes of a building permit, means a construction site that results in the disturbance of less than one acre of land and is not part of a larger common plan of development or sale that would disturb one acre or more.

Special flood hazard area (SFHA) means an area having special flood, mudslide (i.e., mudflow) and/or flood-related erosion hazards and shown on a flood hazard boundary map or flood insurance rate map as zone A, AO, A1-30, AE, A99 or AH.

Stormwater means runoff from rain, snow or other forms of precipitation, which results in surface runoff and drainage.

Stormwater management facilities means structures and constructed features designed for the collection, conveyance, storage, treatment and disposal of stormwater runoff into and through the stormwater system. Stormwater management facilities include vegetative or structural measures, or both, to control the increased volume, rate, and quality of stormwater runoff caused by manmade changes to the land.

Stormwater management plan means an engineering study for the design of the drainage system for a proposed development that includes a map showing the extent of the land development activity, a stormwater pollution prevention plan (SWPPP), stormwater control plan, and may contain as-built certifications and Covenants for Permanent Maintenance of Stormwater Facilities and Best Management Practices. The stormwater management plan also includes sufficient hydrologic calculations to determine the impact of the development on stormwater discharges.

Stormwater management manual means a document prepared and maintained by the county department of engineering which contains design standards and criteria, technical specifications and guidelines, maintenance guidelines, methodology for engineering computations, and other supporting documentation to be used as the technical guidance for implementation of the provisions of this article.

Stormwater master plan means an engineering and planning study for the drainage system of a watershed that consists of a plan for stormwater management in the watershed. Stormwater master plans can address flooding problems, water quality problems, potential stormwater capital improvements, land use patterns, and regulatory issues for existing and future conditions.

Stormwater Pollution Prevention Plan (SWPPP) means a written plan required by the Tennessee General NPDES Permit for Discharges of Stormwater Associated with Construction Activities (TN-CGP) that includes site map(s), an identification of construction/contractor activities that could cause pollutants in the stormwater, and a description of measures or practices to control these pollutants. It must be prepared and approved before construction begins. In order to effectively reduce erosion and sedimentation impacts, best management practices (BMPs) must be designed, installed, and maintained during land disturbing activities. The SWPPP should be prepared in accordance with the Tennessee Erosion and Sediment Control Handbook. The handbook is designed to provide information to planners, developers, engineers, and contractors on the proper selection, installation, and maintenance of BMPs. The handbook is intended for use during the design and construction of projects that require erosion and sediment controls to protect waters of the state. It also aids in the development of SWPPPs and other reports, plans, or specifications required when participating in Tennessee's water quality regulations.

Stormwater system means the system of roadside drainage, roadside curbs and gutters, curb inlets, swales, catch basins, manholes, gutters, ditches, pipes, lakes, ponds, sinkholes, channels, creeks, streams, storm drains, water quality best management practices, and similar conveyances and facilities, both natural and manmade, located within the county which are designated or used for collecting, storing, or conveying stormwater, or through which stormwater is collected, treated, stored or conveyed, whether owned or operated by the county or other person.

Stream, for the specific purpose of water quality buffers, means a linear surface water conveyance that can be characterized with either perennial or ephemeral base flow and:

(1)

Has published floodplain elevations that have been computed as part of an approved flood study;

(2)

Is identified as a blue line on a 7.5-minute USGS quadrangle, unless otherwise designated by TDEC; or

(3)

Is identified by the property owner as a stream; or

(4)

Is or has been identified by the county, USACE or TDEC as a stream.

Structure means anything constructed or erected such that the use of it requires a more or less permanent location on or in the ground. Such construction includes, but is not limited to, objects such as buildings, towers, smokestacks, overhead transmission lines, carports and walls.

TDEC means the Tennessee Department of Environment and Conservation.

Top of bank means the uppermost limit of the active channel of a stream containing normal flows, usually marked by a break in slope.

Total maximum daily load (TMDL) a calculation of the maximum amount of a pollutant that a waterbody can receive and still meet water quality standards, and an allocation of that amount to the source(s) of the pollutant.

Transporting means any moving of earth materials from one place to another, other than such movement incidental to grading, as authorized on an approved plan.

USACE means United States Army Corps of Engineers.

Utility, public or private means any agency which under public franchise or ownership, or under certification of convenience and necessity provides the public with electricity, natural gas, steam, communication, rail transportation, water, sewage collection, or other similar service.

Vegetation means [the] collection of plant life, including trees, shrubs, bushes, and grass.

Wastes, industrial/commercial means liquid or other wastes resulting from any process of industry, manufacture, trade or business, or from the development of any natural resources.

Wastes, other means decayed wood; sawdust; shavings; fallen bark; fallen leaves; lawn clippings; animal wastes; used or previously applied lime; garbage; trash; refuse, loose used paper, paper products, plastic containers, or metal containers; ashes, offal, discarded tar; discarded paint; discarded or uncontained solvents; used, discarded, or spilled petroleum products, antifreeze, motor vehicle fluids; used or discarded tires, gas tanks, or chemicals; or any other used, uncontained, or unpackaged, or disposed of materials which may discharge to or otherwise enter the stormwater system.

Waters or waters of the state mean any and all water, public or private, on or beneath the surface of the ground, which are contained within, flow through or border upon the state or any portion thereof except those bodies of water confined to and retained within the limits of private property in single ownership which do not combine or effect a junction with natural surface or underground waters.

Water quality buffer means a use-restricted, vegetated area that is located along the perimeter of community waters, containing natural vegetation and grasses, enhanced or restored vegetation.

Watercourse means a channel, natural depression, gully, stream, creek, pond, reservoir or lake in which stormwater runoff and floodwater flows either regularly or infrequently. This includes major drainageways for carrying urban stormwater runoff.

Watershed means a region or area bounded peripherally by a divide and draining ultimately to a particular watercourse or body of water.

Wetlands means 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. Wetland determination shall be made by the United States Army Corps of Engineers, and/or the state department of environment and conservation, and/or the natural resources conservation service.

(Ord. No. O-07-12-101, § 2(§ 2), 1-28-08; Ord. No. O-12-11-102, § 1, 12-17-12)