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<br />. <br /> <br />. <br /> <br />. <br /> <br />(c) Outlets. <br /> <br />Discharges from new construction sites must have a stable outlet capable of carrying <br />designed flow at a non-erosive velocity. Outlet design must consider flow capacity and <br />flow duration. This requirement applies to both the site outlet and the ultimate outlet to <br />the storm sewer system or waterbody. Measures to trap floatables for energy dissipation <br />must also be constructed. <br /> <br />(d) Minimize impervious surface area and maximize inf1ltration. <br /> <br />Where directed by the city and based on site feasibility, projects shall use existing natural <br />drainage ways and vegetated soil surfaces to convey, store, f1lter, and retain storm water <br />runoff before discharge into public waters or a storm sewer system (permanent pool <br />areas of wet ponds tend to lose inf1ltration capacity and will not be accepted as an <br />inf1ltration practice). The applicant shall attempt to limit the impervious surface of the <br />developed site or subdivision by incorporating the following design considerations, <br />consistent with zoning, subdivision, and PUD requirements: <br /> <br />1. Natural vegetation preserved wherever practical <br /> <br />2. Narrowing street widths <br /> <br />3. Reducing parking lot space <br /> <br />4. Sidewalk locations <br /> <br />5. Reducing setbacks and driveways <br /> <br />6. Maximizing open space while incorporating smaller lot sizes to conserve natural <br />areas and reduce the amount of storm water runoff generated at the site <br /> <br />7. Using landscaping and soils to treat and infIltrate storm water runoff <br /> <br />8. Eliminate curb and gutter where practicable, and use vegetated swales or equivalent <br /> <br />9. Look for vegetated areas that can futer sheet flow, removing sediment and other <br />pollutants, and increasing the time of concentration <br /> <br />10. Disconnect impervious areas by allowing runoff from small impervious areas to be <br />directed to pervious areas where it can be inf1ltrated or f1ltered <br /> <br />11. All runoff from downspouts, driveways and other impervious areas shall be directed <br />to pervious surfaces, where feasible, or unless the applicant can demonstrate that the <br />practice is likely to result in groundwater contamination <br /> <br />12. Increase buffers around streams, steep slopes, and wetlands to protect from flood <br />damage and provide additional water quality treatment <br /> <br />13 <br />