Wetlland classification, identification, delineation-2005

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SITE DESCRIPTION The subject parcel is approximately 2.6 acres of forest and marsh located at the intersection of North Stream Road and Spring Hill Road(see Figure 1). A cul-de-sac at the end of North Stream Road occurs along the southern edge of the property.One wetland basin lies in the western half along and drains through a tunnel under Spring Hill Road to the north and west. The forest surrounding the wetland basin contains many large cottonwood trees as well as green ash and abundant buckthorn.A small drainage swale leads into the wetland from the east.The topography of the site generally rises gently from the wetland basin in all directions.The surrounding landscape is predominately single- family homes on large wooded lots and a golf course just north of the parcel. METHODS National Wetland Inventory(NWI)maps(Figure 2),Soil Survey of Hennepin County maps(Figure 3),Minnesota Protected Waters maps(Figure 4),and 2003 aerial photographs were reviewed prior to the site visit to identify areas that may be wetlands. Areas illustrating evidence of wetland conditions were examined in greater detail during the field survey. Vegetation, soils and hydrology were examined(as outlined in the 1987 Manual) and used to characterize wetland types and determine wetland boundaries.Sample transects were established in representative wetland-to-upland transition zones in order to characterize the vegetation,soils,and hydrology of the site.Transects consisted of representative upland sample point(s) and representative wetland sample point(s). Information obtained from the sample points can be found on the field data sheets located in Appendix A. The methods used to delineate the subject parcel are as described in the 1987 Manual, under the "routine"methods. This methodology is followed in order to assess whether the three parameters of a wetland are met for areas on the subject parcel. The three parameters required under normal circumstances in order to delineate a wetland are described below. WETLAND CHARACTERISTICS Wetland Hydrology The most important wetland criterion is the hydrology. The presence and persistence of water influences the vegetation types and changes soil morphology. Hydrology may be observed as standing water(inundation), or may be observed as freestanding water within the soil pit or auger hole (saturation) usually within the upper 12 inches. This is what would be considered primary hydrology indicators. Only one primary indicator is necessary to make the determination that wetland hydrology indeed exists. The 1987 Corps Manual also has a range of hydrologic zones established based on period of inundation or saturation. These zones and the periods of inundation or saturation for each are listed in Table 1 below. Excerpted from the 1987 Manual,H drolo is Zones—Nontidal Areas Zone Name Duration Comments Wetland or Not I Permanently Inundated 100% Inundation>6.6 ft.mean Not(Aquatic Habitat Zone,or Deep water depth Water Habitat) Semipermanently To Nearly <75- Inundation defined as II Permanently Inundated Or <100% 56.6 feet mean water Wetland Saturated depth III Regularl Inundated Or Wetland 2 Svoboda Ecological Resources 531 North Stream Road Project No.2005-309-03 Gronberg and Associates