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SECTION II Natural Resources Revolving Fund Plan City of Lino Lakes WSB Project No. 2988-470 Page 4 TMDL Opportunities Several aquatic resources within the City have been identified by the Minnesota Pollution Control Agency (MPCA) as being impaired and have been assigned Total Maximum Daily Load (TMDL) restrictions. Siting wetland restorations upstream of these resources provides an opportunity to remove nutrients and sediment loading, helping to meet TMDL goals. Floodplain Volume Opportunities One of the many functions that wetlands perform is flood control. Many areas within the City are in designated Federal Emergency Management Agency (FEMA) 100-year floodplain. In addition, the Rice Creek Watershed District also regulates floodplain as defined by their model. Restoring or creating wetland banks in and adjacent to these floodplains may provide for an opportunity to address existing flood storage issues or better define the extents of the floodplain area (elevations). Location of Drainage & Utility Easements Once a wetland bank has been established, a conservation easement must be placed over that bank area in perpetuity. Any other easements located in the wetland bank site could be non- compliant with the conservation easement. One common type of easement in wetland areas is a Drainage and Utility easement. Identification of these easements early on will allow for the City review and, if appropriate, abandon the easement prior to finalization of the bank site. Upland Buffers Upland buffers are required to be established by WCA and the ACOE as part of wetland bank construction. Upland buffers provide protection to wetlands by filtering pollutants out of stormwater before it enters the wetland and provides habitat to wildlife. The WCA requires a minimum average buffer width of 25 feet for wetlands that are less than 2 acres. For wetlands that are greater than 2 acres in size the buffer must be a minimum of 25 feet and average 50 feet. The ACOE also requires upland buffers. In municipal areas, ACOE require a minimum of 25-foot buffers. Wetlands in non-municipal areas require a minimum 50-foot buffer. For the purpose of this study, wetland buffer widths of 50-feet were used, except for at sites where the wetland encompassed nearly all of the site. In those situations, any remaining parcel area that was not wetland was included as buffer. These buffers may be expanded or reduced as needed during planning to achieve other goals for the site. B. Mapping Base mapping using ArcGIS was completed to identify the locations of potential wetland bank sites, and how the site related to the site-specific objectives listed above. Data used included FEMA floodplain maps, parcels, Anoka County parks, MPCA impaired waters, Lino Lak es Greenway System mapping, Lino Lakes Wetland Management Corridor mapping, MnRAM restoration potential results, contours, Soil Survey of Anoka County, National Wetland Inventory, and DNR Public Waters Inventory.