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ORDINANCE 2012-036 (e) Discharges from the development project shall be conveyed to a point of legal positive outfall. Tailwater stages of receiving waters must be taken into account in design, and off-site conveyance improvements or enlargement of existing downstream facilities may be required. (f) A dry detention area shall have an outlet device, and the elevation of that device shall not be lower than the elevation of the off-site receiving channel or water body unless protected by a suitably designed flap gate. If the project site is-leeated has direct outfall i -s to an agency system, the use of a flap gate must be approved by that agency. The bottom elevation of a dry detention or retention system or area used for storage, must be a minimum of one (1) foot above the established wet season water table. (g) Where permitted, open drainage -ways shall retain natural design characteristics and be so designed and protected that they do not present a hazard to life or property. The design shall include measures to protect against scour and erosion and provide for stable side slopes. Whenever possible, such waterways shall provide for adequate flushing action by prevailing winds and currents to ensure the prevention of stagnant water and debris accumulation. (h) Disposition of stormwater runoff. The stormwater management system for developments located predominantly on excessively drained soils shall maximize stormwater infiltration. This shall be accomplished through the use of bottomless inlets, perforated pipes, under drains, grading to retard runoff, natural or artificial retention or detention basins, or other methods, depending on the characteristics of the land area. Specific guidelines are as follows: 1. Areas and lots shall be developed to maximize the amount of rainfall which is percolated into the soil and to minimize direct overland runoff into adjoining streets and water courses. Stormwater runoff from roofs and other impervious surfaces shall be diverted into swales, or terraces on the lot. 2. Street drainage shall be by grassed swales, where allowed, or curb and gutter in accordance with county specifications. All curb and gutter systems shall discharge or direct water into a central stormwater tract or across a grassed swale area or other filtering medium. 3. Whenever practical, as indicated by soil characteristics, water table elevation, and topography, the overflow from any swale used shall be diverted to percolation areas, ponding areas or natural or artificial seepage basins of sufficient capacity to retain and provide for the maximum infiltration of stormwater runoff from each drainage area for the design Underline: Additions to Ordinance Strike thr-eugh_- Deleted Text from Existing Ordinance 18 C:\Documents and Settings\tlister\Desktop\Revised IRC Flood Protect Ord final 10-26-12.rtf