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State Wetland Conservation Act (WCA) which is administrated by RCWD as the Local Government Unit (LGU). application to address the wetlands on the site. WCA rules require what is called sequencing whereby the applicant must show efforts to avoid, minimize, rectify, reduce and replace in that order. So even if the County tries to remove all wetlands from TCAAP (most of the 14.4 acres are degraded areas), the final say on what happens to the 4 acre wetland in the blue/green spine rests with possibly the COE and WCA. The next agency that will have say over how the blue/green spine looks and operates is the Rice Creek Watershed District (RCWD). As you are aware, they are the agency responsible for storm water runoff quality, volume control, and runoff rate control. Generally the RCWD water quality requirement is to provide storage for 1.1 inches of rainfall over the impervious area of the entire site. This will result in a fairly large volume of water; approximately 20 acre-feet of infiltration area or 40 acre-feet of ponding. In addition, as detailed in the AUAR, the rate control requirement imposed by RCWD for TCAAP will be 80% of the predevelopment peak runoff rate. This again will result in a significant amount of ponding to detain the runoff and meter it out at the maximum allowable rate (the actual maximum rate will depend on what RCWD determines is the pre-existing condition). As much as possible these ponding and quality control requirements are expected to be met utilizing the blue/green spine area (actual calculations for these requirements are part of the City/County RFP). Finally, as part of our new MS4 permit, the City will be required to come up with policies and regulations for storm water management dealing with Total Phosphorus and Total Suspended Solids in the runoff stream (RCWD will be doing the same). These requirements could possibly be more restrictive than the current RCWD regulations. It is possible and maybe likely that a Storm Water Management plan that meets all of these required regulations will also meet the Councils goal for the aesthetic and passive recreational use of the blue/green spine. However, if the Council can provide some specificity as to what you are expecting for aesthetics and passive recreational use, these items can either be included in or added to the storm water management plan for TCAAP. Some thoughts/questions to help define expectations might be: Does the Council want standing water along the entire length of blue/green spine at all times? (The blue/green spine as shown on the draft master plan is 25-30 acres. Just the RCWD requirement for water quality treatment would mean this area is flooded approximately 1.5 feet deep before adding rate control ponding.) Typically wetlands under WCA and ponds under RCWD will have a buffer strip 5-15 feet wide around them of native or natural growth; is that what the Council envisions? The buffer strip works to prevent contaminants in the runoff from reaching the wetland or ponding area and it also helps discourage large populations of geese. Does the Council envision the area with a natural buffer? 23 Page of