When used in this chapter, the following words and terms shall have the meaning set forth in this section, unless other provisions of this chapter specifically indicate otherwise.
BUILT-UPON AREA (BUA). That portion of a development project that is covered by impervious or partially impervious surface including, but not limited to, buildings; pavement and gravel areas such as roads, parking lots, and paths; and recreation facilities such as tennis courts. BUILT-UPON AREA does not include a wooden slatted deck, the water area of a swimming pool, or pervious or partially pervious paving material to the extent that the paving material absorbs water or allows water to infiltrate through the paving material.
COMMON PLAN OF DEVELOPMENT. 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.
CURB OUTLET SYSTEM. Curb and gutter with breaks or other outlets used to convey stormwater runoff to vegetated conveyances or other vegetated areas.
DESIGN VOLUME. The amount of stormwater runoff that an SCM or series of SCMs is designed to treat.
DEPARTMENT. The North Carolina Department of Environmental Quality.
DESIGN MANUAL. The stormwater design manual approved for use in Phase II jurisdictions by the Department for the proper implementation of the requirements of the federal Phase II stormwater program. All references herein to the Design Manual are to the latest published edition or revision.
DEVELOPMENT. Any land-disturbing activity that increases the amount of built-upon area or that otherwise decreases the infiltration of precipitation into the soil.
DIVISION. The Division means the Division of Energy, Mineral, and Land Resources.
HIGH DENSITY. More than 24% BUA or more than two dwelling units per acre.
LOW DENSITY. No more than 24% BUA or no more than two dwelling units per acre.
MDC. Minimum design criteria as set forth by the Department for stormwater control devices in the Design Manual.
NON-EROSIVE VELOCITY. The flow rate of water, usually measured in feet per second, that does not exceed the maximum permissible shear stress for the condition and type of soil and groundcover over which the water is flowing. Erosion occurs when the maximum permissible shear stress is exceeded.
NON-STRUCTURAL SCM. Preserved open space, natural systems and existing landscape utilized to manage stormwater at its source.
ONE-YEAR, 24-HOUR STORM. 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/pfdsj.
OWNER. The legal or beneficial owner of land, including but not limited to a mortgagee or vendee in possession, receiver, executor, trustee, or long-term or commercial lessee, or any other person or entity holding proprietary rights in the property or having legal power of management and control of the property. OWNER shall include long-term commercial tenants; management entities, such as those charged with or engaged in the management of properties for profit; and every person or entity having joint ownership of the property. A secured lender not in possession of the property does not constitute an owner, unless the secured lender is included within the meaning of OWNER under another description in this definition, such as a management entity.
PEAK ATTENUATION VOLUME. 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.
PRIMARY SCM. A wet pond, stormwater wetland, infiltration system, sand filter, bio-retention cell, permeable pavement, green roof, rainwater harvesting, or an approved new stormwater technology that is designed, constructed and maintained in accordance with the MDC.
PROJECT. The proposed development activity for which an applicant is seeking a stormwater permit from the town 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.
REDEVELOPMENT. Any development on previously developed land, other than a rebuilding activity that results in no net increase in built-upon area and provides equal or greater stormwater control than the previous development.
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 one inch in depth that is treated in one or more primary SCMs or a combination of primary and secondary SCMs that provides equal or better treatment.
RUNOFF VOLUME MATCH. The annual runoff volume after development shall not be more than 10% higher than the annual runoff volume before development.
SCM. Stormwater control measure; also known as BMP or best management practice; 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.
STRUCTURAL SCM. A physical device designed to trap, settle out, or filter pollutants from stormwater runoff; to alter or reduce stormwater runoff velocity, amount, timing, or other characteristics; to approximate the pre-development hydrology on a developed site; or to achieve any combination of these goals. Structural SCMs includes physical practices such as constructed wetlands, vegetative practices, filter strips, grassed swales, and other methods installed or created on real property. STRUCTURAL SCM is synonymous with "structural practice," "stormwater control facility," "stormwater control practice," "stormwater treatment practice," "stormwater management practice," "stormwater control measures," "structural stormwater treatment systems," and similar terms used in this chapter.
SUBSTANTIAL PROGRESS. For the purposes of determining whether sufficient progress has been made on an approved plan, one or more of the following construction activities toward the completion of a site or subdivision plan shall occur: obtaining a grading permit and conducting grading activity on a continuous basis and not discontinued for more than 30 days; or installation and approval of on-site infrastructure; or obtaining a building permit for the construction and approval of a building foundation. SUBSTANTIAL PROGRESS for purposes of determining whether an approved plan is null and void is not necessarily the same as "substantial expenditures" used for determining vested rights pursuant to applicable law.
TOWN. Town of Clayton, NC.
WORKING DAYS. Days exclusive of Saturday and Sunday and federal and state holidays observed by the town.
(Ord. 2020-11-01, passed 11-16-20)