[Added 8-6-2024 by Ord. No. 2024.08.06B]
The following words and terms, when used in this division, shall have the following meanings, unless the context clearly indicates otherwise.
ADEQUATE CHANNEL
Means a channel that will convey the designated frequency storm event without overtopping the channel bank nor causing erosive damage to the channel bed or banks.
AGREEMENT IN LIEU OF A PLAN
Means a contract between the Town of Abingdon and the owner or permittee that specifies methods that shall be implemented to comply with the requirements of the VESMA and this division for the construction of a: (i) single-family detached residential structure; or (ii) farm building or structure on a parcel of land with a total impervious cover percentage, including the impervious cover from the farm building or structure to be constructed, of less than 5%; such contract may be executed by the Town of Abingdon in lieu of a soil erosion control and stormwater management plan.
APPLICANT
Means person submitting a soil erosion control and stormwater management plan to a VESMP authority for approval in order to obtain authorization to commence a land-disturbing activity.
BEST MANAGEMENT PRACTICE or BMP
Means schedules of activities, prohibitions of practices, maintenance procedures, and other management practices, including both structural and nonstructural practices, to prevent or reduce the pollution of surface waters and groundwater systems.
(1)
NONPROPRIETARY BEST MANAGEMENT PRACTICE
Means both structural and nonstructural practices to prevent or reduce the pollution of surface waters and groundwater systems that are in the public domain and are not protected by trademark or patent or copyright.
(2)
PROPRIETARY BEST MANAGEMENT PRACTICE
Means both structural and non-structural practices to prevent or reduce the pollution of surface waters and groundwater systems that are privately owned and controlled and may be protected by trademark or patent or copyright.
BOARD
Means the State Water Control Board.
CAUSEWAY
Means a temporary structural span constructed across a flowing watercourse or wetland to allow construction traffic to access the area without causing erosion damage.
CHANNEL
Means a natural stream or manmade waterway.
CHESAPEAKE BAY PRESERVATION ACT
Means Article 2.5 (§ 62.1-44.15:67 et seq.) of Chapter 3.1 of Title 62.1 of the Code of Virginia.
CHESAPEAKE BAY PRESERVATION AREA
Means any land designated by a local government pursuant to Part III (9VAC25-830-70 et seq.) of the Chesapeake Bay Preservation Area Designation and Management Regulations and § 62.1-44.15:74 of the Code of Virginia. A Chesapeake Bay Preservation Area shall consist of a Resource Protection Area and a Resource Management Area as defined in the Chesapeake Bay Preservation Area Designation and Management Regulations (9VAC25-830).
CLEAN WATER ACT or CWA
Means the Federal Clean Water Act (33 USC § 1251 et seq.), formerly referred to as the Federal Water Pollution Control Act or Federal Water Pollution Control Act Amendments of 1972, Public Law 92-500, as amended by Public Law 95-217, Public Law 95-576, Public Law 96-483, and Public Law 97-117, or any subsequent revisions thereto.
COFFERDAM
Means a watertight temporary structure in a river, lake, etc., for keeping the water from an enclosed area that has been pumped dry so that bridge foundations, dams, etc., may be constructed.
COMMON PLAN OF DEVELOPMENT OR SALE
Means a contiguous area where separate and distinct construction activities may be taking place at different times on different schedules.
COMPREHENSIVE STORMWATER MANAGEMENT PLAN
Means a plan, which may be integrated with other land use plans or regulations that specifies how the water quality components, quantity components, or both of stormwater are to be managed on the basis of an entire watershed or a portion thereof. The plan may also provide for the remediation of erosion, flooding, and water quality and quantity problems caused by prior development.
CONSTRUCTION ACTIVITY
Means any clearing, grading, or excavation associated with large construction activity or associated with small construction activity.
CONTROL MEASURE
Means any BMP, stormwater facility, or other method used to minimize the discharge of pollutants to state waters.
CWA AND REGULATIONS
Means the Clean Water Act and applicable regulations published in the Code of Federal Regulations promulgated thereunder. For the purposes of this division, it includes state program requirements.
DAM
Means a barrier to confine or raise water for storage or diversion, to create a hydraulic head, to prevent gully erosion, or to retain soil, rock or other debris.
DENUDED
Means a term applied to land that has been physically disturbed and no longer supports vegetative cover.
DEPARTMENT
Means the Virginia Department of Environmental Quality.
DEVELOPMENT
Means land disturbance and the resulting landform associated with the construction of residential, commercial, industrial, institutional, recreation, transportation, or utility facilities or structures or the clearing of land for non-agricultural or non-silvicultural purposes. The regulation of discharges from development, for purposes of stormwater management, does not include the exclusions found in 9VAC25-875-860.
DIKE
Means an earthen embankment constructed to confine or control water, especially one built along the banks of a river to prevent overflow of lowlands; levee.
DISCHARGE
When used without qualification, means the discharge of a pollutant.
DISCHARGE OF A POLLUTANT
Means
(1)
Any addition of any pollutant or combination of pollutants to state waters from any point source; or
(2)
Any addition of any pollutant or combination of pollutants to the waters of the contiguous zone or the ocean from any point source other than a vessel or other floating craft which is being used as a means of transportation.
DISTRICT or SOIL AND WATER CONSERVATION DISTRICT
Means a political subdivision of the Commonwealth organized in accordance with the provisions of Article 3 (§ 10.1-506 et seq.) of Chapter 5 of Title 10.1 of the Code of Virginia.
DIVERSION
Means a channel with a supporting ridge on the lower side constructed across or at the bottom of a slope for the purpose of intercepting surface runoff.
DORMANT
Means denuded land that is not actively being brought to a desired grade or condition.
DRAINAGE AREA
Means a land area, water area, or both from which runoff flows to a common point.
ENERGY DISSIPATOR
Means a nonerodable structure which reduces the velocity of concentrated flow to reduce its erosive effects.
ENVIRONMENTAL PROTECTION AGENCY or EPA
Means the United States Environmental Protection Agency.
EROSION AND SEDIMENT CONTROL PLAN
Means a document containing material for the conservation of soil and water resources of a unit or group of units of land. It may include appropriate maps, an appropriate soil and water plan inventory and management information with needed interpretations, and a record of decisions contributing to conservation treatment. The plan shall contain all major conservation decisions to ensure that the entire unit or units of land will be treated to achieve the conservation objectives.
EROSION IMPACT AREA
Means an area of land that is not associated with a current land-disturbing activity but is subject to persistent soil erosion resulting in the delivery of sediment onto neighboring properties or into state waters. This definition shall not apply to any lot or parcel of land of 10,000 square feet or less used for residential purposes or to shorelines where the erosion results from wave action or other coastal processes.
ESC
Means erosion and sediment control.
ESM PLAN
Means a soil erosion control and stormwater management plan, commonly referred to as the erosion control and stormwater management plan.
FARM BUILDING OR STRUCTURE
Means the same as that term is defined in § 36-97 of the Code of Virginia and also includes any building or structure used for agritourism activity, as defined in § 3.2-6400 of the Code of Virginia, and any related impervious services including roads, driveways, and parking areas.
FLOOD FRINGE
Means the portion of the floodplain outside the floodway that is usually covered with water from the 100-year flood or storm event. This includes the flood or floodway fringe designated by the Federal Emergency Management Agency.
FLOOD-PRONE AREA
Means the component of a natural or restored stormwater conveyance system that is outside the main channel. Flood-prone areas may include the floodplain, the floodway, the flood fringe, wetlands, riparian buffers, or other areas adjacent to the main channel.
FLOODING
Means a volume of water that is too great to be confined within the banks or walls of the stream, water body, or conveyance system and that overflows onto adjacent lands, thereby causing or threatening damage.
FLOODPLAIN
Means the area adjacent to a channel, river, stream, or other water body that is susceptible to being inundated by water normally associated with the 100-year flood or storm event. This includes the floodplain designated by the Federal Emergency Management Agency.
FLOODWAY
Means the channel of a river or other watercourse and the adjacent land areas, usually associated with flowing water, that must be reserved in order to discharge the 100-year flood or storm event without cumulatively increasing the water surface elevation more than one foot. This includes the floodway designated by the Federal Emergency Management Agency.
FLUME
Means a constructed device lined with erosion-resistant materials intended to convey water on steep grades.
GENERAL PERMIT
Means a permit authorizing a category of discharges under the CWA and the VESMA within a geographical area.
HYDROLOGIC UNIT CODE or HUC
Means a watershed unit established in the most recent version of Virginia's 6th Order National Watershed Boundary Dataset unless specifically identified as another order.
IMPERVIOUS COVER
Means a surface composed of material that significantly impedes or prevents natural infiltration of water into soil.
INCORPORATED PLACE
Means a city, town, township, or village that is incorporated under the Code of Virginia.
INSPECTION
Means an on-site review of the project's compliance with any applicable design criteria, or an on-site review to obtain information or conduct surveys or investigations necessary in the implementation or enforcement of the VESMA and applicable regulations.
KARST AREA
Means any land area predominantly underlain at the surface or shallow subsurface by limestone, dolomite, or other soluble bedrock regardless of any obvious surface karst features.
KARST FEATURES
Means sinkholes, sinking and losing streams, caves, large flow springs, and other such landscape features found in karst areas.
LAND DISTURBANCE or LAND-DISTURBING ACTIVITY
Means a manmade change to the land surface that may result in soil erosion or has the potential to change its runoff characteristics, including construction activity such as the clearing, grading, excavating, or filling of land.
LAND-DISTURBANCE APPROVAL
Means an approval allowing a land-disturbing activity to commence issued by the VESMP authority after the requirements of § 62.1-44.15:34 of the Code of Virginia have been met.
LARGE CONSTRUCTION ACTIVITY
Means construction activity including clearing, grading, and excavation, except operations that result in the disturbance of less than five acres of total land area. Large construction activity also includes the disturbance of less than five acres of total land area that is a part of a larger common plan of development or sale if the larger common plan will ultimately disturb five acres or more. Large construction activity does not include routine maintenance that is performed to maintain the original line and grade, hydraulic capacity, or original purpose of the facility.
LINEAR DEVELOPMENT PROJECT
Means a land-disturbing activity that is linear in nature, such as, but not limited to: (i) the construction of electric and telephone utility lines, and natural gas pipelines; (ii) construction of tracks, rights-of-way, bridges, communication facilities and other related structures of a railroad company; (iii) highway construction projects; (iv) construction of stormwater channels and stream restoration activities; and (v) water and sewer lines. Private subdivision roads or streets shall not be considered linear development projects.
LIVE WATERCOURSE
Means a definite channel with bed and banks within which concentrated water flows continuously.
LOCALITY
Means Town of Abingdon.
LOCALIZED FLOODING
Means smaller scale flooding that may occur outside of a stormwater conveyance system. This may include high water, ponding, or standing water from stormwater runoff, which is likely to cause property damage or unsafe conditions.
MAIN CHANNEL
Means the portion of the stormwater conveyance system that contains the base flow and small frequent storm events.
MANMADE
Means constructed by man.
MINIMIZE
Means to reduce or eliminate the discharge of pollutants to the extent achievable using stormwater controls that are technologically available and economically practicable.
MINOR MODIFICATION
Means modifications and amendments not requiring extensive review and evaluation including changes in EPA promulgated test protocols, increasing monitoring frequency requirements, changes in sampling locations, and changes to compliance dates within the overall compliance schedules. A minor permit modification or amendment does not substantially alter permit conditions, substantially increase or decrease the amount of surface water impacts, increase the size of the operation, or reduce the capacity of the facility to protect human health or the environment.
NATURAL CHANNEL DESIGN CONCEPTS
Means the utilization of engineering analysis and fluvial geomorphic processes to create, rehabilitate, restore, or stabilize an open conveyance system for the purpose of creating or recreating a stream that conveys its bankfull storm event within its banks and allows larger flows to access its bankfull bench and its floodplain.
NATURAL STREAM
Means a tidal or nontidal watercourse that is part of the natural topography. It usually maintains a continuous or seasonal flow during the year and is characterized as being irregular in cross-section with a meandering course. Constructed channels such as drainage ditches or swales shall not be considered natural streams; however, channels designed utilizing natural channel design concepts may be considered natural streams.
NONERODABLE
Means a material, e.g., riprap, concrete, plastic, etc., that will not experience surface wear due to natural forces.
NONPOINT SOURCE POLLUTION
Means pollution such as sediment, nitrogen, phosphorus, hydrocarbons, heavy metals, and toxics whose sources cannot be pinpointed but rather are washed from the land surface in a diffuse manner by stormwater.
OPERATOR
Means the owner or operator of any facility or activity subject to the VESMA and this division. In the context of stormwater associated with a large or small construction activity, operator means any person associated with a construction project that meets either of the following two criteria: (i) the person has direct operational control over construction plans and specifications, including the ability to make modifications to those plans and specifications; or (ii) the person has day-to-day operational control of those activities at a project that are necessary to ensure compliance with a stormwater pollution prevention plan for the site or other permit or VESMP authority permit conditions (i.e., they are authorized to direct workers at a site to carry out activities required by the stormwater pollution prevention plan or comply with other permit conditions).
OWNER
Means the same as that term is defined in § 62.1-44.3 of the Code of Virginia. For a regulated land-disturbing activity that does not require a permit, "owner" also means the owner or owners of the freehold of the premises or lesser estate therein, mortgagee or vendee in possession, assignee of rents, receiver, executor, trustee, lessee, or other person, firm, or corporation in control of a property.
PEAK FLOW RATE
Means the maximum instantaneous flow from a prescribed design storm at a particular location.
PERCENT IMPERVIOUS
Means the impervious area within the site divided by the area of the site multiplied by 100.
PERMIT
Means a VPDES permit issued by the department pursuant to § 62.1-44.15 of the Code of Virginia for stormwater discharges from a land-disturbing activity.
PERMITTEE
Means the person to whom the permit is issued.
PERSON
Means any individual, partnership, firm, association, joint venture, public or private corporation, trust, estate, commission, board, public or private institution, utility, cooperative, county, city, town, or other political subdivision of the Commonwealth, governmental body, including a federal or state entity as applicable, any interstate body, or any other legal entity.
POINT OF DISCHARGE
Means a location at which concentrated stormwater runoff is released.
POINT SOURCE
Means any discernible, confined, and discrete conveyance including any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, landfill leachate collection system, vessel, or other floating craft from which pollutants are or may be discharged. This term does not include return flows from irrigated agriculture or agricultural stormwater runoff.
POLLUTANT DISCHARGE
Means the average amount of a particular pollutant measured in pounds per year or another standard reportable unit as appropriate, delivered by stormwater runoff.
POLLUTION
Means such alteration of the physical, chemical, or biological properties of any state waters as will or is likely to create a nuisance or render such waters: (a) harmful or detrimental or injurious to the public health, safety, or welfare, or to the health of animals, fish or aquatic life; (b) unsuitable with reasonable treatment for use as present or possible future sources of public water supply; or (c) unsuitable for recreational, commercial, industrial, agricultural, or other reasonable uses, provided that: (i) an alteration of the physical, chemical, or biological property of state waters, or a discharge or deposit of sewage, industrial wastes or other wastes to state waters by any owner which by itself is not sufficient to cause pollution, but which, in combination with such alteration of or discharge or deposit to state waters by other owners, is sufficient to cause pollution; (ii) the discharge of untreated sewage by any owner into state waters; and (iii) contributing to the contravention of standards of water quality duly established by the State Water Control Board, are "pollution" for the terms and purposes of this division.
POST-DEVELOPMENT
Refers to conditions that reasonably may be expected or anticipated to exist after completion of the land development activity on a specific site or tract of land.
PREDEVELOPMENT
Refers to the conditions that exist at the time that plans for the land-disturbing activity are submitted to the VESMP authority. Where phased development or plan approval occurs (preliminary grading, demolition of existing structures, roads and utilities, etc.), the existing conditions at the time prior to the commencement of land-disturbing activity shall establish predevelopment conditions.
PRIOR DEVELOPED LANDS
Means land that has been previously utilized for residential, commercial, industrial, institutional, recreation, transportation, or utility facilities or structures, and that will have the impervious areas associated with those uses altered during a land-disturbing activity.
QUALIFIED PERSONNEL
Means a person knowledgeable in the principles and practices of erosion and sediment and stormwater management controls who possesses the skills to assess conditions at the construction site for the operator that could impact stormwater quality and quantity and to assess the effectiveness of any sediment and erosion control measures or stormwater management facilities selected to control the quality and quantity of stormwater discharges from the construction activity.
RESPONSIBLE LAND DISTURBER or RLD
Means an individual holding a certificate issued by the department who is responsible for carrying out the land-disturbing activity in accordance with the approved erosion and sediment control plan or ESM plan. The RLD may be the owner, applicant, permittee, designer, superintendent, project manager, contractor, or any other project or development team member. The RLD must be designated on the erosion and sediment control plan. ESM plan, or permit as defined in this division as a prerequisite for engaging in land disturbance.
RUNOFF CHARACTERISTICS
Includes maximum velocity, peak flow rate, volume, and flow duration.
RUNOFF or STORMWATER RUNOFF
Means that portion of precipitation that is discharged across the land surface or through conveyances to one or more waterways.
RUNOFF VOLUME
Means the volume of water that runs off the land development project from a prescribed storm event.
SEDIMENT BASIN
Means a temporary impoundment built to retain sediment and debris with a controlled stormwater release structure.
SEDIMENT TRAP
Means a temporary impoundment built to retain sediment and debris which is formed by constructing an earthen embankment with a stone outlet.
SHEET FLOW (also called OVERLAND FLOW)
Means shallow, unconcentrated and irregular flow down a slope. The length of strip for overland flow usually does not exceed 200 feet under natural conditions.
SHORELINE EROSION CONTROL PROJECT
Means an erosion control project approved by local wetlands boards, the Virginia Marine Resources Commission, the department, or the United States Army Corps of Engineers and located on tidal waters and within non-vegetated or vegetated wetlands as defined in Title 28.2 of the Code of Virginia.
SITE
Means the land or water area where any facility or land-disturbing activity is physically located or conducted, including adjacent land used or preserved in connection with the facility or land-disturbing activity. Areas channel-ward of mean low water in tidal Virginia shall not be considered part of a site.
SITE HYDROLOGY
Means the movement of water on, across, through, and off the site as determined by parameters including soil types, soil permeability, vegetative cover, seasonal water tables, slopes, land cover, and impervious cover.
SLOPE DRAIN
Means tubing or conduit made of nonerosive material extending from the top to the bottom of a cut or fill slope with an energy dissipator at the outlet end.
SMALL CONSTRUCTION ACTIVITY
Means:
(1)
Construction activities including clearing, grading, and excavating that result in land disturbance of equal to or greater than one acre and less than five acres. Small construction activity also includes the disturbance of less than one acre of total land area that is part of a larger common plan of development or sale if the larger common plan will ultimately disturb equal to or greater than one and less than five acres. Small construction activity does not include routine maintenance that is performed to maintain the original line and grade, hydraulic capacity, or original purpose of the facility. The department may waive the otherwise applicable requirements in a general permit for a stormwater discharge from construction activities that disturb less than five acres where stormwater controls are not needed based on an approved "total maximum daily load" (TMDL) that addresses the pollutants of concern or, for nonimpaired waters that do not require TMDLs, an equivalent analysis that determines allocations for small construction sites for the pollutants of concern or that determines that such allocations are not needed to protect water quality based on consideration of existing in-stream concentrations, expected growth in pollutant contributions from all sources, and a margin of safety. For the purpose of this subdivision, the pollutants of concern include sediment or a parameter that addresses sediment (such as total suspended solids, turbidity, or siltation) and any other pollutant that has been identified as a cause of impairment of any water body that will receive a discharge from the construction activity. The operator shall certify to the department that the construction activity will take place, and stormwater discharges will occur, within the drainage area addressed by the TMDL or provide an equivalent analysis. As of the start date in Table 1 of 9VAC25-31-1020, all certifications submitted in support of the waiver shall be submitted electronically by the owner or operator to the department in compliance with this subdivision and 40 CFR Part 3 (including, in all cases, 40 CFR Part 3 Subpart D), 9VAC25-875-940, and Part XI (9VAC25-31-950 et seq.) of the Virginia Pollutant Discharge Elimination System (VPDES) Permit Regulation. Part XI of 9VAC25-31 is not intended to undo existing requirements for electronic reporting. Prior to this date, and independent of Part XI of 9VAC25-31, permittees may be required to report electronically if specified by a particular permit.
(2)
Any other construction activity designated by either the department or the EPA regional administrator, based on the potential for contribution to a violation of a water quality standard or for significant contribution of pollutants to surface waters.
SOIL EROSION
Means the movement of soil by wind or water into state waters or onto lands in the Commonwealth.
SOIL EROSION CONTROL AND STORMWATER MANAGEMENT PLAN
Commonly referred to as the erosion control and stormwater management plan, or "ESM plan" means a document describing methods for controlling soil erosion and managing stormwater in accordance with the requirements adopted pursuant to the VESMA. The ESM plan may consist of aspects of the erosion and sediment control plan and the stormwater management plan as each is described in this division.
STABILIZED
Means land that has been treated to withstand normal exposure to natural forces without incurring erosion damage.
STATE
Means the Commonwealth of Virginia.
STATE APPLICATION or APPLICATION
Means the standard form or forms, including any additions, revisions, or modifications to the forms, approved by the administrator and the department for applying for a permit.
STATE WATER CONTROL LAW
Means Chapter 3.1 (§ 62.1-44.2 et seq.) of Title 62.1 of the Code of Virginia.
STATE WATERS
Means all water, on the surface and under the ground, wholly or partially within or bordering the Commonwealth or within its jurisdiction, including wetlands.
STORM SEWER INLET
Means a structure through which stormwater is introduced into an underground conveyance system.
STORMWATER CONVEYANCE SYSTEM
Means a combination of drainage components that are used to convey stormwater discharge, either within or downstream of the land-disturbing activity. This includes:
(1)
MANMADE STORMWATER CONVEYANCE SYSTEM
Means a pipe, ditch, vegetated swale, or other stormwater conveyance system constructed by man except for restored stormwater conveyance systems;
(2)
NATURAL STORMWATER CONVEYANCE SYSTEM
Means the main channel of a natural stream and the flood-prone area adjacent to the main channel; or
(3)
RESTORED STORMWATER CONVEYANCE SYSTEM
Means a stormwater conveyance system that has been designed and constructed using natural channel design concepts. Restored stormwater conveyance systems include the main channel and the flood-prone area adjacent to the main channel.
STORMWATER DETENTION
Means the process of temporarily impounding runoff and discharging it through a hydraulic outlet structure to a downstream conveyance system.
STORMWATER MANAGEMENT FACILITY
Means a control measure that controls stormwater runoff and changes the characteristics of that runoff including the quantity and quality, the period of release or the velocity of flow.
STORMWATER MANAGEMENT PLAN
Means a document containing material describing methods for complying with the requirements of the VESMP.
STORMWATER POLLUTION PREVENTION PLAN or SWPPP
Means a document that is prepared in accordance with good engineering practices and that identifies potential sources of pollutants that may reasonably be expected to affect the quality of stormwater discharges. A SWPPP required under the VESMP for construction activities shall identify and require the implementation of control measures and shall include or incorporate by reference an approved erosion and sediment control plan, an approved stormwater management plan, and a pollution prevention plan.
STORMWATER
For the purposes of the VESMA, means precipitation that is discharged across the land surface or through conveyances to one or more waterways and that may include stormwater runoff, snow melt runoff, and surface runoff and drainage.
SUBDIVISION
Means the same as defined in § 15.2-2201 of the Code of Virginia.
SURFACE WATERS
Means:
(1)
All waters that are currently used, were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters that are subject to the ebb and flow of the tide;
(2)
All interstate waters, including interstate wetlands;
(3)
All other waters such as intrastate lakes, rivers, streams (including intermittent streams), mudflats, sandflats, wetlands, sloughs, prairie potholes, wet meadows, playa lakes, or natural ponds the use, degradation, or destruction of which would affect or could affect interstate or foreign commerce including any such waters:
a.
That are or could be used by interstate or foreign travelers for recreational or other purposes:
b.
From which fish or shellfish are or could be taken and sold in interstate or foreign commerce; or
c.
That are used or could be used for industrial purposes by industries in interstate commerce;
(4)
All impoundments of waters otherwise defined as surface waters under this definition;
(5)
Tributaries of waters identified in subdivisions (1) through (4) of this definition;
(7)
Wetlands adjacent to waters (other than waters that are themselves wetlands) identified in subdivisions 1 through 6 of this definition.
SWM
Means stormwater management.
TEMPORARY VEHICULAR STREAM CROSSING
Means a temporary nonerodable structural span installed across a flowing watercourse for use by construction traffic. Structures may include bridges, round pipes or pipe arches constructed on or through nonerodable material.
TEN-YEAR STORM
Means a storm that is capable of producing rainfall expected to be equaled or exceeded on the average of once in 10 years. It may also be expressed as an exceedance probability with a 10% chance of being equaled or exceeded in any given year.
TOTAL MAXIMUM DAILY LOAD or TMDL
Means the sum of the individual wasteload allocations for point sources, load allocations (LAs) for nonpoint sources, natural background loading, and a margin of safety. TMDLs can be expressed in terms of either mass per time, toxicity, or other appropriate measure. The TMDL process provides for point versus nonpoint source trade-offs.
TOWN
Means Town of Abingdon.
TWO-YEAR STORM
Means a storm that is capable of producing rainfall expected to be equaled or exceeded on the average of once in two years. It may also be expressed as an exceedance probability with a 50% chance of being equaled or exceeded in any given year.
VIRGINIA EROSION AND STORMWATER MANAGEMENT ACT or VESMA
Means Article 2.3 (§ 62.1-44.15:24 et seq.) of Chapter 3.1, State Water Control Law, of Title 62.1 of the Code of Virginia.
VIRGINIA EROSION AND STORMWATER MANAGEMENT PROGRAM AUTHORITY or VESMP AUTHORITY
Means Town of Abingdon approved by the department to operate the VESMP.
VIRGINIA EROSION AND STORMWATER MANAGEMENT PROGRAM or VESMP
Means a program established by the VESMP authority for the effective control of soil erosion and sediment deposition and the management of the quality and quantity of runoff resulting from land-disturbing activities to prevent the unreasonable degradation of properties, stream channels, waters, and other natural resources. The program shall include such items as local ordinances, rules, requirements for permits and land-disturbance approvals, policies and guidelines, technical materials, and requirements for plan review, inspection, and enforcement consistent with the requirements of the VESMA.
VIRGINIA POLLUTANT DISCHARGE ELIMINATION SYSTEM (VPDES) PERMIT or VPDES PERMIT
Means a document issued by the department pursuant to the State Water Control Law authorizing, under prescribed conditions, the potential or actual discharge of pollutants from a point source to surface waters.
VIRGINIA STORMWATER BMP CLEARINGHOUSE
Means a collection that contains detailed design standards and specifications for control measures that may be used in Virginia to comply with the requirements of the VESMA and associated regulations.
VIRGINIA STORMWATER MANAGEMENT HANDBOOK
Means a collection of pertinent information that provides general guidance for compliance with the VESMA and associated regulations and is developed by the department with advice from a stakeholder advisory committee.
WASTELOAD ALLOCATION or WASTELOAD
Means the portion of a receiving surface water's loading or assimilative capacity allocated to one of its existing or future point sources of pollution. Wasteload allocations are a type of water quality-based effluent limitation.
WATER QUALITY TECHNICAL CRITERIA
Means standards set forth in regulations adopted pursuant to the VESMA that establish minimum design criteria for measures to control nonpoint source pollution.
WATER QUANTITY TECHNICAL CRITERIA
Means standards set forth in regulations adopted pursuant to the VESMA that establish minimum design criteria for measures to control localized flooding and stream channel erosion.
WATERSHED
Means a defined land area drained by a river or stream, karst system, or system of connecting rivers or streams such that all surface water within the area flows through a single outlet. In karst areas, the karst feature to which water drains may be considered the single outlet for the watershed.
WETLANDS
Means those areas that are inundated or saturated by surface water or groundwater at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs, and similar areas.