Agenda - Planning Commission - 05/01/2003

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Item 12 Mitigation Element. Wetland Sequencing - Minnesota Rules 8420, also known as the Wetland Conservation Act (WCA), requires specific steps ("sequencing") be taken when evaluating mitigation for unavoidable wetland impacts. The WCA requires that wetland impacts be avoided, if possible. If wetland avoidance cannot be accomplished, impacts to wetlands need to be minimized. Finally, any wetland impacts that can not either be avoided or minimized to the extent possible, must be mitigated though wetland replacement. The wetland replacement must mitigate all wetland functions and values lost as part of the wetland impact. The degradation present on site allows the applicant to evaluate sequencing flexibility in their mitigation plan. It also allows the Technical Evaluation Panel (TEP) the opportunity to be flexible on the sequencing provisions of the WCA rule. This process may only be applied in the event the wetlands on-site are degraded to the point where replacement of the wetland would result in a gain in functions and values. This is an item that will be considered by the TEP during the permitting process. Wetlands located on site are described in the Wetland Delineation Report (Appendix A), and are discussed in Item 10. With a few exceptions, wetlands located within the boundaries of the RTC are either cropped or are of low quality. These wetlands have marginal functions and values due to their low vegetative diversity, partial drainage and lack of connectivity to other nearby wetlands and natural areas. Sequencing is addressed as follows: Avoidance: The better quality portions of existing wetlands are generally avoided. This includes ali ofwetlands B, C and D. Minimization: The mix of development proposed as part of the RTC requires that retail, commercial and residential land use blocks are a minimum size with adequate infrastructure to service them. The focus of minimization has been to incorporate as much of existing wetland area into a central greenway corridor, thereby lowering overall wetland loss across the project site. To avoid indirect impacts to remaining wetlands, each of the development blocks will incorporate a treatment train of stormwater best management practices designed to improve water quality and lower wetland bounce magnitude and duration. Currently, row cropping occurs into the wetlands. The RTC will incorporate wetland buffers wherever practical. I i I I I I I I ! I I I I, Ii Wetland Replacement: The LRRWMO Stormwater Management Plan provides that the following may be eligible for wetland replacement credits: 36 · Creation of"new" wetland - Rules, Sub-part 11; · Addition of"public value" Rules, Sub-part 6; · "Public value" restoration from invasive species to permanent native, non- invasive species - Rules, Sub-part 8; and