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<br /> <br />(c) Outlets. Discharges from new construction sites must have a stable outlet capable of <br />carrying designed flow at a non-erosive velocity. Outlet design must consider flow capacity <br />and flow duration. This requirement applies to both the site outlet and the ultimate outlet <br />to the storm sewer system or waterbody. Measures to trap floatables for energy dissipation <br />must also be constructed. <br />(d) Minimize impervious surface area and maximize infiltration. Where directed <br /> <br />b. <br />by the city and based on site feasibility, projects shall use existing natural drainage <br />ways and vegetated soil surfaces to convey, store, filter, and retain stormwater <br />runoff before discharge into public waters or a storm sewer system (permanent <br />pool areas of wet ponds tend to lose infiltration capacity and will not be accepted <br />as an infiltration practice). <br />Redevelopment. Projects shall have no increase in runoff from <br />the pre-project peak runoff rates for the 2, 10, and 100 year 24 hour storm events. <br /> <br />8.Treatment design sequencing for sites with restrictions (as found in the MIDS Design <br />Sequence Flowchart). <br />Applicant shall fully attempt to comply with the appropriate performance goals described <br />above. Options considered and presented shall examine the merits of relocating project <br />elements to address, varying soil conditions and other constraints across the site. If full <br />compliance is not possible due to any of the factors listed below, the applicant must <br />document the reason. If site constraints or restrictions limit the full treatment goal, the <br />following treatment design sequence shall be followed: <br />Applicant shall document the treatment sequence starting with Alternative #1. If Alternative <br />#1 cannot be met, then Alternative #2 shall be analyzed. Applicants must document the <br />specific reasons why Alternative #1 cannot be met based on the factors listed below. If <br />Alternative #2 cannot be met then Alternative #3 shall be met. Applicants must document <br />the specific reasons why Alternative #2 cannot be met based on the factors listed below. <br />When all of the conditions are fulfilled within an alternative, this sequence is completed. <br />Volume reduction techniques considered shall include infiltration, reuse & rainwater <br />harvesting, and canopy interception & evapotranspiration and/or additional techniques <br />included in the MIDS calculator and the Minnesota Stormwater Manual. <br />Higher priority shall be given to BMPs that include volume reduction. Secondary preference <br />is to employ filtration techniques, followed by rate control BMPs. Factors to be considered <br />for each alternative will include: <br /> <br />i.Karst geology <br /> <br />ii.Shallow bedrock <br /> <br />iii.High groundwater <br /> <br />iv.Hotspots or contaminated soils <br /> <br />v.Drinking Water Source Management Areas or within 200 feet of drinking water <br />well <br /> <br />vi.Zoning, setbacks or other land use requirements <br /> <br />vii.Excessive cost <br /> <br />viii.Poor soils (infiltration rates that are too low or too high, problematic urban <br />soils) <br />Alternative #1: <br />Applicant Attempts to Comply with the Following Conditions: <br /> Page <br />17 <br />