(A) All projects not subject to more stringent standards shall meet the stormwater system design requirements set forth in 15A NCAC 02H .1003. Projects shall use a project density threshold of 24% built-upon area or greater, whereupon high-density stormwater design is required. All engineered stormwater controls will meet the standards set in the Manual of Standard Designs and Details (MSDD) and the state's Minimum Design Criteria (MDC), 15A NCAC 02H .1050 through .1062.
(B) Where high-density stormwater design is required, stormwater systems shall meet the standards set forth in 15A NCAC 02H .1003(3) and be designed to control and treat the volume of runoff generated from all built-upon area by one inch of rainfall or equivalent runoff volume in one or more primary SCMs or combination of primary and secondary SCMs that provides equal or better treatment. These projects may utilize offsite SCMs dedicated to treating an area encompassing the project.
(C) Phased projects may have a combination of low-density and high-density phases.
(D) Low density projects or phases may be expanded and redeveloped to increase to high-density at which time the high-density requirements in subsection (B) of this section shall apply to the project or phase.
(Ord. No. 24-021, § 1, passed 4-11-2024)