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Little Canada Zoning Code Stormwater Management 928-5 (8) Hydrologic calculations for volume runoff, velocities, and peak flow rates by watershed, for the 2.0-yr, 10-yr, and 100-yr 24-hour storm events. These shall include: (a) Pre and Post construction peak flow rates (b) Assumed runoff curve numbers. (c) Time of concentration used in calculations. (d) If a flood insurance study has been done by the National Flood Insurance Program, the 100-year flood elevation with and without the floodway. (9) Hydrologic calculations documenting pollution reduction of 90% total suspended solids removal for new construction and 45% total suspended solids removal for redevelopment sites from the runoff generated by a NURP water quality storm (2.5” rainfall). (10) Bankfull discharge rate (1.5 year recurrence interval) of creek or stream if there is a waterway on the site or if the site discharges directly to the waterway. (11) Locations of all stormwater management practices, infiltration areas, and areas not to be disturbed during construction (12) Steep slopes where areas of 12% or more existing over a distance for 50 feet or more. (13) Location of temporary sedimentation basins - If more than 10 acres are disturbed and drained to a single point of discharge temporary sediment basins must be installed, however, if the site has sensitive features as determined by the City or the potential of off site impacts, then temporary sediment basins must be installed to protect the resource. This is determined on a site by site basis. When site restrictions do not allow for a temporary sediment basin, equivalent measures such as smaller basins, check dams, and vegetated buffer strips can be included. (14) Location and engineered designs for structural stormwater management practices including stormwater treatment devices that remove oil and floatable material (e.g., basin outlets with submerged entrances). (15) Normal water level, high water level, and emergency overflow elevations for the site. (16) Floodway and flood fringe boundary, if available. d. All proposed stormwater practices, hydrologic models, and design methodologies shall be reviewed by City and certified for compliance by the City in accordance with their plans and specifications.