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Article 6: Development Standards 82 <br /> Section 6.14: Stormwater Management <br /> 6.14.4 General Methods <br /> The following general approaches shall be utilized to minimize the effects of stormwater pollution <br /> on hydrologically connected aquatic ecosystems and144 drinking water supplies in Orange <br /> County: <br /> (A) Non-Structural Stormwater Control Measures (SCMs)Methods145 <br /> (1) The stormwater run-off generated by one inch of rain from all project area <br /> surfaces shall be controlled to the extent possible through on-site infiltration and <br /> through the use of methods which rely on natural soil properties for absorption <br /> and treatment. <br /> (2) Run-offStormwater runoff from roads, parking lots, and/or sidewalks shall be <br /> directed to undisturbed areas through use of berms, grassed diversion ditches or <br /> swales, or other acceptable means to reduce run e stormwater runoff velocity <br /> and volume, and filter out pollutants. <br /> (3) Impervious Surface Limits <br /> (a) In order to promote infiltration of stormwater runoff into the soil and <br /> minimize direct and immediate runoff into streams and water supply <br /> impoundments, the maximum percentage of the total lot area which may <br /> be covered with an impervious surface shall be specified. This limit is <br /> referred to as the "impervious surface ratio". <br /> (b) Impervious surface calculations for an individual development shall be <br /> cumulative for original construction and any subsequent additions. One- <br /> half of the width of any of any existing or proposed road adjacent to an <br /> individual lot shall be included as impervious surface for that lot, except <br /> in the case where an existing road was contained within a dedicated <br /> public right-of-way at the time that the watershed regulations were first <br /> applied to the watershed within which the development is located. <br /> (4) Infiltration Tech,�`hn:,uesSystems146 <br /> (a) The benefits of onfoltratiGR teGhR'queslnfiltration Systems include, but are <br /> not limited t0147: <br /> (i) Removal of both suspended and dissolved pollutants, <br /> (ii) They require loos maintenanGoRelatively low maintenance <br /> requirements, <br /> (iii) They reduce flood ^^Flood reduction, <br /> (iv) They prom GtePromotion of groundwater recharge, and <br /> (v) They help maiRtaORMaintenance of stream flow during dry <br /> periods.148 <br /> 144 Added "hydrologically connected aquatic ecosystems"—NOTE: This is a staff recommendation to help the <br /> general public understand that Orange County is not just trying to protect human focused drinking water <br /> supplies,but also our aquatic ecosystems that are hydrologically connected. <br /> 141 Replaced "Non-Structural Stormwater Control Measures(SCMs)"with "Non-Structural Methods"so as to avoid <br /> confusion with permanent Stormwater Control Measures(SCMs)—NOTE: "Non-Structural Methods"is integrated <br /> through the remainder of Section 6.14, where applicable. <br /> 141"Infiltration Techniques" replaced with "Infiltration Systems"so as to better reflect the definition and <br /> terminology contained in 15A NCAC 02H.1002(Definitions)—NOTE: 'Infiltration Systems"is integrated through <br /> the remainder of Section 6.14, where applicable. <br /> 141 Text correction—added ", but not limited to". <br /> 141 Text correction—grammar fixes within list. <br /> Orange County, North Carolina—Unified Development Ordinance Page 6-98 <br />