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Wetlands rated low for shoreline protection. While these wetlands are not providing the highest level of protection to the lake or river systems, their mere presence provides some level of protection that should not be dismissed. These wetlands are typically narrow, with little emergent, submergent, or floating-leaved vegetation. Wetlands rated Medium for aesthetics/education/recreation/cultural and Low for wildlife habitat. 1.1.4 Manage 3 Manage 3 Wetlands classified as include all of the remaining wetlands that did not fit into any of the Alllow above-described conditions. of these wetlands would rate for vegetative diversity/integrity. Many of these wetlands rate medium or high for downstream water quality protection and for flood storage/attenuation. This correlation is expected since wetlands that provide higher levels of water quality treatment and runoff/rate control often suffer from ecological degradation. 1.2 Wetland Restoration Potential Evaluate restoration potential of drained and partially drained wetlands in the field. The potential for wetland restoration is determined based on the ease with which the wetland could be restored considering factors including: the number of landowners within the historic wetland area, the size of the potential restoration area, the potential for establishing buffer areas or water quality ponding, the extent and type of hydrologic alteration, and the potential for flooding adjacent properties. Using those parameters, a functional rating of High, Medium, or Low is computed where High means that there will be fewer obstacles to completing a successful restoration. 1.3 Wetland Susceptibility to Stormwater Input Stormwater runoff carries soil particles, nutrients, and contaminants that can change the ecological balance of the receiving water body. Changes in the volume, rate, frequency, or duration of stormwater entering or discharging from the water body can also change the ecological integrity. Alterations to the ecological integrity of a wetland often result in changes in the functional capacity, fish and wildlife habitat, replacement of native vegetation with invasive and disturbance-tolerant plant species, and/or other impacts to the wetland’s functions and values. 6 A methodology for determining the susceptibility of wetlands to degradation by stormwater input relates wetland type to a susceptibility level as shown in Table 1.2. Wetlands such as bogs and fens can easily be degraded by changes in the stormwater inflows and are designated as exceptionally susceptible. On the other hand, floodplain forests are more tolerant of changes in the frequency, magnitude and duration of flooding without degradation and are therefore classified as moderately susceptible. Shallow marshes and wet meadows dominated by hybrid cattail, reed canary grass, or other invasive/non-native species (see Table 1.2 and MNRAM 3.0) have a moderate susceptibility to stormwater fluctuations and inputs. 6 Storm-Water and Wetlands: Planning and Evaluation Guidelines for Addressing Potential Impacts of Urban Storm-Water and Snow-Melt Runoff on Wetlands (State of Minnesota Storm Water Advisory Group, 1997). Management Classification 6