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surface and subsurface water. The constancy of the seasonal patterns from year to year ensures a <br /> reasonable stability for the wetland (Mitsch and Gosselink, 2000). The ability of the wetland to <br /> maintain a hydrologic regime characteristic of the wetland type is evaluated based upon wetland soil <br /> and vegetation characteristics, land use within the wetland, land use•within the upland watershed <br /> contributing to the wetland, and wetland outlet configuration. Maintenance of the hydrologic regime <br /> is important for maintaining a characteristic vegetative community, and is closely associated with ' <br /> other functions including flood attenuation, water quality and groundwater interaction. <br /> Maximum Score: 2 � <br /> 4.2.1.3 Flood/Stormwater Attenuation <br /> A wetland's ability to provide flood storage and/or flood wave attenuation is dependent on many <br /> characteristics of the wetland and contributing watershed. Characteristics of the subwatershed that <br /> affect the wetlands ability to provide flood storage and attenuation include: soil types, land use and <br /> resulting stormwater runoff volume, sediment delivery from the subwatershed, and the abundance of <br /> wetlands and waterbodies in the subwatershed. Wetland characteristics which affect the wetland's <br /> ability to store and or attenuate stormwater include: condition of wetland soils;presence, extent, and <br /> type of wetland vegetation;presence and connectivity of channels; and most importantly outlet . <br /> configuration. Higher rated wetlands will have an unaltered or restricted outlet, undisturbed wetland <br /> soils, dense emergent vegetation without channels, a high proportion of impervious surfaces in the � <br /> subwatershed, large runoff volumes, clayey upland soils, and few wetlands present within the <br /> subwatershed. � <br /> Maximum Score: 1 , <br /> 4.2.1.4 Downstream Water Quality Protection <br /> This rates the wetland's ability and opportunity to protect valuable downstream resources. Valuable <br /> downstream resources include recreational waters and potable water supplies including all of Lake <br /> Minnetonka, Minnehaha Creek and other recreational lakes. The level of functioning is determined <br /> based on runoff characteristics, sedimentation processes,nutrient cycling, and the presence and <br /> location of significant downstream water resources. Runoff characteristics that are evaluated include: <br /> land use and soils in the upstream watershed, the stormwater delivery system to the wetland, and <br /> sediment delivery characteristics. The ability of the wetland to remove sediment from stormwater is <br /> determined by emergent vegetation and overland flow characteristics. A high nutrient removal rating <br /> \\fred\wp�23�27�D06Uteports�Final Report\Wetland_mgmt�lan_dit011503.doc 4-13 <br />