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'�, , CITY OF ORONO - ORONO POLICE STATION GARAGE EXPANSION Introduction This report is prepared for the City of Orono to identify wetlands in the area of the Orono police statio in Orono, MN. Figure 1 shows the location of the project area.The field investigation for this wetland delineation was conducted on May 8, 2008. This delineation report provides the required documentati n for wetland boundary determinations in conformance with the Minnesota Wetland Conservation Act a d Section 404 of the Clean Water Act. Methods Preliminary Investigation: The National Wetlands Inventory(NWI)was examined with the 2005 aerial photograph to identify pote tial wetlands on the site(Figures 2). The Hennepin County Soil Survey was examined to determine addition I areas of potential wetlands(Figures 3). Cordova loam, Le Seuer loam and Hamel-Glencoe, depressional, complex are hydric soils located on the site. Hydric soils are good indicators of potential wettand areas. One jurisdictional wetland was identified within the project area(Figures 4). Wetland Delineation: Wetlands were identified using standard delineation methodology described in the 1987 Army Corps of Engineers(COE)Wetland Delineation Manual as required by both the Minnesota Wetland Conservation ct and Section 404 of the Clean Water Act. To verify a site is wetland,three technical criteria are examined and documented. A combination of the hydric soil, hydrophytic vegetation, and hydrology criteria defines wetlands as described in the National Food Security Act Manual(Soil Conservation Service, 1994)and th Corps of Engineers Wetlands Delineation Manual(Environmental Laboratory, 1987). Therefore, an area t at meets the hydric soil criteria must also meet the hydrophytic vegetation and wetland hydrology criteria in order for it to be classified as a jurisdictional wetland. A hyd�icsoilis a soil that formed under conditions of saturation,flooding or ponding long enough during the growing season to develop anaerobic conditions in the upper part. The concept of hydric soils include soils developed under sufficiently wet conditions to support the growth and regeneration of hydrophytic vegetation. Soils that are sufficiently wet because of artificial measures are included in the concept of hyd c soils.Also, soils in which the hydrology has been artificially modified are hydric if the soil, in an unaltered state,was hydric(USDA, NRCS 1999).A hydric soil list provided by the National Technical Committee for Hydric Soils(NTTCHS)and the County Soil Survey was used to determine the potential locations of hydric soils for this site. Hyd�ophytic vegetation is defined as the sum total of macrophytic plant life that occurs in areas where the frequency and duration of inundation or soil saturation produce permanently or periodically saturated soils of sufficient duration to exert a controlling influence on the plant species present. Plant species within the wetland/upland ecotone were recorded as to their percent cover and wetland indicator status according to the National list of Plant Species that occur in wetlands; North Central Region 3 (USFWS Biological Report 88, 26.3; May 1988). The term wetland hydro%qyencompasses all hydrologic characteristics for areas that are periodically inundated or have soils saturated to the surface at some time during the growing season. COE hydrology criteria consist of inundation or saturation to the surface for at least 5%of the growing season in most City of O�ano Projecl No: 139-08019 WeHand Delineation Report �Bonestroo Page 1