Erosion, Flood, Stormwater & Watershed Standards 12.5 Stormwater Management
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(primarily, ongoing farming and forestry activities), are exempt from the stormwater management provisions of this section. C. Concurrency with State Neuse River Basin Standards: All development and redevelopment in the jurisdiction of this ordinance shall comply with the standards of the Neuse River Basin: Nutrient Sensitive Waters Management Strategy: Protection and Maintenance of Riparian Areas with Existing Forest Vegetation, adopted as a permanent rule 1 August 2000 (15A NCAC 2B.0233), as amended. D. Deed Restriction or Covenants Required: The approval of a stormwater permit shall require an enforceable restriction on property usage that runs with the land, such as a recorded deed restriction or protective covenants, to ensure that future development and redevelopment maintains the site consistent with the approved plan. E. Calculation Requirements: All stormwater calculations (runoff, pipe, ditch and inlet sizing, outlet protection, and detention routing (if required)) shall be submitted to the Administrator. Calculations shall consider inlet and outlet control, hydraulic grade line and backwater as applicable. All detention facilities shall be designed to attenuate developed condition peak discharges to the existing conditions for the given storm as described in the Manual of Specifications, Standards and Design.
12.5.2. Standards For Low Density Development/ Impervious Surface Projects
Low impervious surface projects shall include those developments that have no more than 24% built upon area for all residential and non-residential development. Total project area shall include total acreage in the tract on which the project is to be developed. In addition to complying with the project density development requirements of each water supply watershed in 12.6.1.D, low impervious surface projects shall comply with each of the following standards: A. Runoff Transport: Stormwater runoff shall be transported by vegetated conveyances to the maximum extent practicable. 1. Vegetated Conveyances. Stormwater runoff from the project shall be released to vegetated areas as dispersed flow or transported by vegetative conveyances to the maximum extent practicable. Vegetative conveyances shall be maintained in perpetuity to ensure that they function as designed. Vegetative conveyances shall meet the minimum design criteria of 15A NCAC 02B.0624 5 (a). 2. Curb Outlet Systems. Curb and gutter systems with outlets to convey stormwater to grassed swales or vegetated areas may be used in lieu of vegetated conveyances if designed and constructed to meet the minimum design criterial of 15A NCAC 02B.0624 5(b). 3. Treatment swales may be used in lieu of vegetated conveyances and curb outlet systems if designed in accordance with 15A NCAC 02H.1061. B. Watercourse Buffers (Minimum Each Side) : See Section 12.7. 12.5.3. Standards For High Density Development/ Impervious Surface Projects A. High impervious surface projects shall include those developments that have more than 24% built upon area for all residential and non-residential development. Total project area shall include total acreage in the tract on which the project is to be developed. In addition to complying with the project density requirements of each water supply watershed in 12.6.1.D, high impervious surface projects shall comply with each of the following standards: B. Runoff Volume: Stormwater control measures shall be installed that control and treat the difference in stormwater runoff volume leaving the project site between the pre- and post-development conditions for, at a minimum, the 1-year, 24-hour storm. The post-development peak runoff rate shall be limited to the predevelopment peak runoff
Town of Wake Forest Unified Development Ordinance – July 19, 2022
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