Agenda - Environmental Policy Board - 10/15/2018

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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 all of wetlands 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 lowelhig 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 ilicuipui ate wetland buffers wherever practical. Wetland Replacement: The LRRWMO Stormwater Management Plan provides that the following may be eligible for wetland replacement credits: • Creation of mew" 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 • Incorporation of -water quality treatment ponds" under the criteria contained in Sub -part 10(A* and B), with nature of -eredit" determined by LRRWMO. *The City of Ramsey has adopted the LRRWMO stormwater management plan by reference for this portion of the City, thus qualifying the City for eligibility under this element. As Table 12.2 shows, a total of 6.94 acres of wetland will be impacted and require replacement. A central feature of the RTC is a greenway corridor running though the central portion of the site. A system of stormwater ponds, infiltration swales and meandering channels will link flows entering the site from the northwest with flows generated on -site. This -waterway" will continue south from the RTC to the Mississippi River. Within the context of this waterway system, on -site wetland replacement will be provided though a combination of new wetlands, upland buffers and water quality improvement ponds designed to improve functions and values to downstream wetlands. The location of proposed on -site wetland replacement is shown in Figures 12.3 and 12.4. Table 12.3 summarizes the acreage and type of wetland replacement for each location. A general description for each wetland replacement site follows. 12-6