Orange County NC Website
Article 6: Development Standao'll <br /> Section 6.14:Stormwater Management <br /> (1) Allowable on-site SCMs for nutrient <br /> reduction shall include those listed in the most current version179 of the North <br /> Carolina Administrative Code Title 15A, Subchapter 02H, Sections .1000 through <br /> .1062, and the most current version of the NCDEQ Stormwater Design Manual. <br /> (2) Design, maintenance and operation of 180SCMs shall follow <br /> standards provided in the most current version181 of the North Carolina <br /> Administrative Code Title 15A, Subchapter 02H, Sections .1000 through .1062, <br /> and the most current version of the NCDEQ Stormwater Design Manual. <br /> (3) Deviations from these standards may be allowed as approved on a case by case <br /> basis. <br /> (F) Total Nutrient Removal Rates <br /> Total nutrient removal rates of SCMs, as well as SCMs in a series, will be calculated <br /> pursuant to the approved accounting tools 182. <br /> 6476.14.8 Peak Runoff Volume <br /> (A) Standards for Falls Lake Watershed <br /> (1) For all new development, there shall be no net increase in peak flow leaving the <br /> site from the pre development conditions for the 1,--year, 24--hour storm. <br /> (B) Standards for Jordan Lake Watershed <br /> (1) For all new development there shall be no net increase greater than 10% in peak <br /> flow leaving the site from the pre-development conditions consistent with 15-A <br /> NCAC 02H.1002 (44 <br /> 184 <br /> (C) Calculating Peak Runoff Volume <br /> (1) The following are acceptable methodologies for computing the pre- and post- <br /> development conditions for the 1--year, 24_-hour storm: <br /> (a) Rational Method, <br /> (b) Peak Discharge Method as described in the USDA Soil Conservation <br /> Service's Technical Release Number 55 (TR-55), <br /> (c) Alternative methods must be approved by the County. <br /> (2) The same method must be used for both the pre- and post-development <br /> conditions. <br /> 614 86.14.9 Stormwater Management Plan SMP 18s <br /> (A) Required Approval <br /> 179 Consistent reference to "most current versions"of Subchapter 02H andthe NCDEQ Stormwater Design Manual. <br /> 180 Text correction—deleted "stormwater". <br /> 181 Consistent reference to "most current versions"of Subchapter 02H andthe NCDEQ Stormwater Design Manual. <br /> 182 Text correction—added "s". <br /> 184 Reference to 15A NCAC 02H.1002 (44)is sufficient. <br /> 185 Title of Section 6.14.9 revised to includethe appropriate acronym for Stormwater Management Plans(SMPs)— <br /> NOTE. "Stormwater Management Plan"and"SMP"are integrated through the remainder of Section 6.14, <br /> where applicable. <br /> Orange County, North Carolina— Unified Development Ordinance Page 6-103 <br />