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Article 6: Development Standards 111 <br /> Section 6.14: Stormwater Management <br /> (B) Additional Standards— Falls Lake Watershed <br /> (1) In addition to the standards contained in Section 6.14.6 (A) of the UD9this <br /> Ordinance168, development shall observe a no net increase in peak flow leaving <br /> the site from predevelopment conditions for the 1 year, 24 hour, storm. <br /> (2) Proposed new development using a Runoff Volume Match design approach for <br /> satisfying stormwater management requirements must also include the <br /> estimation of pre-development and post-development nutrient export rates (e.q. <br /> Nitrogen and Phosphorous)for the proposed development, using the nutrient <br /> accounting methodologies approved by the North Carolina Division of Water <br /> Resources (NCDWR). Nutrient export estimates are required for Runoff Volume <br /> Match record-keeping purposes.169 <br /> (C) Additional Standards—Jordan Lake Watershed <br /> � �naa �o��a <br /> 0) IR a.dditiOR to the standards GGRtaiRed OR SeGtien F 1n 6 (A) of the I Inn!bk <br /> fdiRaP,Ge47-0 development shall abode by 15 A NGAG 02H 1002 inns 171 <br /> ti <br /> 6.14.66.14.7 Nutrient Load <br /> (A) Nitrogen and phosphorus loads contributed by proposed new development shall not <br /> exceed the following unit-area mass loading rates: <br /> (1) Falls Lake Watershed <br /> (a) Nitrogen, 2.2 pounds per acre per year <br /> (b) Phosphorus, 0.33 pounds per acre per year <br /> (B) The nutrient export from each new development shall be calculated in pounds per acre <br /> per year(using the approved accounting tools172) in accordance with the methodologies <br /> approved by the North Carolina Division of Water Resources (NCDWR).173 <br /> (C) If a proposed development subject to nutrient load requirements contributes nutrients <br /> greater than the standards listed above, the developer may install sterrnwateF,.GRtFGI <br /> rReasures (SCnn&)SCMs to meet the required nutrient load standards or do a combination <br /> of SCMs and offset payments-to achieve the standard. <br /> (D) Offset Payments <br /> (1) Offset fees may be permitted to meet the nutrient export levels set for new <br /> development. In order to utilize offset fees, the proposed new development <br /> subject to the nutrient load standards must attain nitrogen and phosphorus <br /> loading rate reductions on-site that meet the following criteria prior to using an <br /> offsite offset measure: <br /> (a) Falls Lake Watershed <br /> (i) 30% or more reduction in both nitrogen and phosphorus loading <br /> from the untreated conditions for any single-family, detached and <br /> duplex residential development disturbing one half acre but less <br /> than one acre; <br /> (ii) 50% or more reduction in both nitrogen and phosphorus loading <br /> 16s Consistent reference to"this Ordinance". <br /> "I Required per the state's most current Neuse-Tar-Pamlico Rules. <br /> Consistent reference to "this 9rd-inance". <br /> 171 Section 6.14.6(C) is no longer needed, as the allowable use of"Runoff Volume Match" methodology applies to <br /> both the Falls Lake Watershed and the Jordan Lake Watershed, as specified in revised Section 6.14.6(A). <br /> 171 Text correction—added "s". <br /> 171 Revised to refer to NCDWR for approved nutrient accounting tools, rather than NCDEQ. <br /> Orange County, North Carolina—Unified Development Ordinance Page 6-101 <br />