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4. Provide maintenance access to stormwater features in form of a recreational, multi‐use trail 5. Provide wetland mitigation for site development to the extent feasible 6. Provide infiltration for site development (residential, retail, and commercial parcels) to the extent feasible 7. Accommodate other passive recreation opportunities where feasible Existing Conditions As shown on the attached Exhibit A, the existing site drainage is split with roughly 60 percent of the site draining to Rice Creek and the southern 40 percent of the site draining to Round Lake. The RCWD requires that the existing volumes to these waters be maintained in the future condition, and the peak discharge rate be reduced as the site is developed. There are 14.4 acres of wetland on the site (Exhibit B). The RCWD and Army Corps have different jurisdiction and mitigation requirements for the wetlands impacted. A minimum of 6.5 acres of mitigation is needed on site to satisfy RCWD and Corps requirements for the site infrastructure (construction of the Spine and Thumb roads, CR I roundabout, natural resource corridor grading) as shown in Exhibit C. This amount does not include the creek realignment, however that work is expected to be self‐mitigating. Grading Concept Plan The current infrastructure plan shows the conceptual layout of the natural resource corridor (Exhibit C). We are continuing to coordinate with the regulatory agencies on the design details and there are revisions that may occur as planning and permitting proceed. This grading work will be completed as a part of the TCAAP public infrastructure improvements. The proposed grading plan accomplishes the following priorities: 1. Provide all wetland replacement for the public infrastructure impacts 2. Accommodate all required stormwater rate control and infiltration for Spine/Thumb Roads 3. Accommodate stormwater rate control for all TCAAP site development 4. Provide maintenance access to stormwater features in form of a recreational, multi‐use trail 7. Provide some space for passive recreation opportunities along the easterly portion of the site Depending on further coordination with the Army Corps and RCWD, there is room in the natural resource corridor to meet either priority 5 or priority 6, however which is implemented has not been determined. If a permit from the Corps cannot be obtained for wetland impacts of future development, the proposed grading plan would not provide wetland replacement (priority #5) for future site development within the natural resource corridor, requiring individual developments that impact wetlands to address mitigation needs separately as a part of their planning and design activities. In that case, infiltration BMPs would be incorporated into the natural resource corridor (priority #6) rather than additional wetland mitigation. What will it look like? The design details are still in the planning stage, however we have a number of images to be presented at the work session that depict the general look of the different features that may be included within the natural resource corridor.