15A NCAC 02H .1002       DEFINITIONS

The definition of any word or phrase in this Section shall be the same as given in Article 21, Chapter 143 of the General Statutes of North Carolina, as amended.  Definitions set forth in 15A NCAC 02H .0150 and 40 CFR 122.2 and 122.26(b) (1 July 2015 Edition) are incorporated herein by reference, not including subsequent amendments and editions.  These federal regulations may be accessed at no cost at http://www.gpo.gov/fdsys/.  Other words and phrases used in this Section are defined as follows:

(1)           "Adverse impact" means a detrimental effect upon water quality or best usages, including a violation of water quality standards, caused by or contributed to by a discharge or loading of a pollutant or pollutants.

(2)           "Best usage" means those uses of waters specified for each classification as determined by the Commission in accordance with the provisions of G.S. 143-214.1 and as set forth in 15A NCAC 02B .0101, 15A NCAC 02B .0200, and 15A NCAC 02B .0300.

(3)           "Built-upon area" or "BUA" has the same meaning as in G.S. 143-214.7.

(4)           "CAMA Major Development Permits" means those permits or revised permits required by the Coastal Resources Commission as set forth in 15A NCAC 07J Sections .0100 and .0200. 

(5)           "Certificate of Stormwater Compliance" means the approval for activities that meet the requirements for coverage under a stormwater general permit for development activities that are regulated by this Section.

(6)           "Coastal Counties" means any of the following counties: Beaufort, Bertie, Brunswick, Camden, Carteret, Chowan, Craven, Currituck, Dare, Gates, Hertford, Hyde, New Hanover, Onslow, Pamlico, Pasquotank, Pender, Perquimans, Tyrrell, and Washington.

(7)           "Commission" means the North Carolina Environmental Management Commission.

(8)           "Common plan of development" means a site where multiple separate and distinct development activities may be taking place at different times on different schedules but governed by a single development plan regardless of ownership of the parcels.  Information that may be used to determine a "common plan of development" include plats, blueprints, marketing plans, contracts, building permits, public notices or hearings, zoning requests, and infrastructure development plans.

(9)           "Curb Outlet System" means curb and gutter with breaks or other outlets used to convey stormwater runoff to vegetated conveyances or other vegetated areas.

(10)         "Design volume" means the amount of stormwater runoff that an SCM or series of SCMs is designed to treat.

(11)         "Development" has the same meaning as in G.S. 143-214.7.

(12)         "Director" means the Director of the Division of Energy, Mineral, and Land Resources.

(13)         “Dispersed flow" means uniform shallow flow that is conveyed to a vegetated filter strip as defined in Rule .1059 of this Section, another vegetated area, or stormwater control measure.  The purpose of "dispersed flow" is to remove pollutants through infiltration and settling, as well as to reduce erosion prior to stormwater reaching surface waters.

(14)         "Division" means the Division of Energy, Mineral, and Land Resources.

(15)         "Drainage Area or Watershed" means the entire area contributing surface runoff to a single point.

(16)         "Erosion and Sedimentation Control Plan" means any plan, amended plan, or revision to an approved plan submitted to the Division of Energy, Mineral, and Land Resources or a delegated authority in accordance with G.S. 113A-57.

(17)         "Existing development" means those projects that are built or those projects that have established a vested right under North Carolina law as of the effective date of the state stormwater program or applicable local government ordinance to which the project is subject.

(18)         "General Permit" means a permit issued under G.S. 143-215.1(b)(3) and G.S. 143-215.1(b)(4) authorizing a category of similar activities or discharges.

(19)         "Geotextile fabric" means a permeable geosynthetic comprised solely of non-biodegradable textiles.

(20)         "Infiltration Systems" means stormwater control measures designed to allow runoff to move into the soil's pore space.

(21)         "Intermittent stream" has the same meaning as in 15A NCAC 02B .0233.

(22)         "Local government" has the same meaning as in 15A NCAC 02B .0202.

(23)         "Major modification" means a change of a state stormwater permit that is not a "minor modification" as that term is defined in this Rule.

(24)         "Minimum Design Criteria" or "MDC" means the requirements set forth in this Section for siting, site preparation, design and construction, and post-construction monitoring and evaluation necessary for the Department to issue stormwater permits that comply with State water quality standards adopted pursuant to G.S. 143-214.1.

(25)         "Minor modification" means a change of a state stormwater permit that does not increase the net built-upon area within the project or does not increase the overall size of the stormwater control measures that have been approved for the project.

(26)         "Non-erosive velocity" means the flow rate of water, usually measured in feet per second, that does not exceed the maximum permissible velocity for the condition and type of soil and groundcover over which the water is flowing.  Erosion occurs when the maximum permissible velocity is exceeded.

(27)         "Notice of Intent" means a written notification to the Division that an activity or discharge is intended to be covered by a general permit in lieu of an application for an individual permit.

(28)         "NPDES" means National Pollutant Discharge Elimination System.

(29)         "Off-site Stormwater Systems" means stormwater management systems that are located outside the boundaries of the specific project in question, but designed to control stormwater drainage from that project and other potential development sites. 

(30)         "One-year, 24-hour storm" means the maximum amount of rainfall during a 24 consecutive hour period expected, on average, to occur once a year.  One-year, 24-hour storm depths are estimated by the National Oceanic and Atmospheric Administration (NOAA) Precipitation Frequency Data Server (PFDS), which is herein incorporated by reference, including subsequent amendments and editions, and may be accessed at no cost at http://hdsc.nws.noaa.gov/hdsc/pfds/.

(31)         "On-site Stormwater Systems" means the systems necessary to control stormwater within an individual development project and located within the project boundaries.

(32)         "Peak attenuation volume" means stormwater runoff in excess of the design volume that is conveyed to an SCM where it is not treated in accordance with the applicable MDC, but is released by the SCM in a controlled manner to address potential downstream erosion and flooding impacts to meet federal, State, or local regulations beyond the requirements of this Section.

(33)         "Perennial waterbody" has the same meaning as in 15A NCAC 02B .0233.

(34)         "Perennial stream" has the same meaning as in 15A NCAC 02B .0233.

(35)         "Permeable pavement" means paving material that absorbs water or allows water to infiltrate through the paving material.  "Permeable pavement" materials include porous concrete, permeable interlocking concrete pavers, concrete grid pavers, porous asphalt, and any other material with similar characteristics.

(36)         "Person" has the same meaning as in G.S. 143-212(4).

(37)         "Primary SCM" means a wet pond, stormwater wetland, infiltration system, sand filter, bioretention cell, permeable pavement, green roof, rainwater harvesting, or an approved new stormwater technology that is designed, constructed and maintained in accordance with the MDC.

(38)         "Project" means the proposed development activity for which an applicant is seeking a stormwater permit from the state or other entity in accordance with this Section.  "Project" shall exclude any land adjacent to the area disturbed by the project that has been counted as pervious by any other development regulated under a federal, State, or local stormwater regulation.  Owners and developers of large developments consisting of many linked projects may consider developing a master plan that illustrates how each project fits into the design of the large development.

(39)         "Public linear transportation project" means a project consisting of a road, bridge, sidewalk, greenway, or railway that is on a public thoroughfare plan or provides improved access for existing development and that is owned and maintained by a public entity.

(40)         "Required storm depth" means the minimum amount of rainfall that shall be used to calculate the required treatment volume or to evaluate whether a project has achieved runoff volume match.

(41)         "Redevelopment" has the same meaning as in G.S. 143-214.7.

(42)         "Residential development" has the same meaning as in 15A NCAC 02B .0202.

(43)         "Runoff treatment" means that the volume of stormwater runoff generated from all of the built-upon area of a project at build-out during a storm of the required storm depth is treated in one or more primary SCMs or a combination of Primary and Secondary SCMs that provides equal or better treatment. 

(44)         "Runoff volume match" means that the annual runoff volume after development shall not be more than ten percent higher than the annual runoff volume before development, except in areas subject to SA waters requirements per Rule .1019 of this Section where runoff volume match means that the annual runoff volume after development shall not be more than five percent higher than the annual runoff volume before development.

(45)         "Seasonal High Water Table" or "SHWT" means the highest level of the saturated zone in the soil during a year with normal rainfall.  SHWT may be determined in the field through identification of redoximorphic features in the soil profile, monitoring of the water table elevation, or modeling of predicted groundwater elevations.

(46)         "Secondary SCM" means an SCM that does not achieve the annual reduction of Total Suspended Solids (TSS) of a "Primary SCM" but may be used in a treatment train with a primary SCM or other Secondary SCMs to provide pre-treatment, hydraulic benefits, or a portion of the required TSS removal.

(47)         "Stormwater" has the same meaning as in G.S.143-213(16a).

(48)         "Stormwater Collection System" means any conduit, pipe, channel, curb, or gutter for the primary purpose of transporting (not treating) runoff.  A stormwater collection system does not include vegetated swales, swales stabilized with armoring, or alternative methods where natural topography or other physical constraints prevents the use of vegetated swales (subject to case-by-case review), curb outlet systems, or pipes used to carry drainage underneath built-upon surfaces that are associated with development controlled by the provisions of Rule .1003 in this Section.

(49)         "Stormwater Control Measure" or "SCM," also known as "Best Management Practice" or "BMP," means a permanent structural device that is designed, constructed, and maintained to remove pollutants from stormwater runoff by promoting settling or filtration; or to mimic the natural hydrologic cycle by promoting infiltration, evapo-transpiration, post-filtration discharge, reuse of stormwater, or a combination thereof.

(50)         "Ten-year storm intensity" means the maximum rate of rainfall of a duration equivalent to the time of concentration expected, on the average, once in 10 years. Ten-year storm intensities are estimated by the National Oceanic and Atmospheric Administration (NOAA) Precipitation Frequency Data Server (PFDS), which is herein incorporated by reference, including subsequent amendments and editions, and may be accessed at no cost at http://hdsc.nws.noaa.gov/hdsc/pfds/.

(51)         "Vegetated setback" means an area of natural or established vegetation adjacent to surface waters, through which stormwater runoff flows in a diffuse manner to protect surface waters from degradation due to development activities.

(52)         "Vegetated conveyance" means a permanent, designed waterway lined with vegetation that is used to convey stormwater runoff at a non-erosive velocity within or away from a developed area.

(53)         "Water Dependent Structures" means a structure that requires access, proximity to, or siting within surface waters to fulfill its basic purpose, such as boat ramps, boat houses, docks, or bulkheads. Ancillary facilities such as restaurants, outlets for boat supplies, parking lots, and boat storage areas shall not be considered water dependent structures.

 

History Note:        Authority G.S. 143-213; 143-214.1; 143-214.7; 143-215.3(a)(1);

Eff. January 1, 1988;

Amended Eff. August 1, 2012 (see S.L. 2012-143, s.1. (f)); July 3, 2012; December 1, 1995; September 1, 1995;

Temporary Amendment Eff. March 28, 2014;

Amended Eff. January 1, 2015;

Readopted Eff. January 1, 2017.