Laserfiche WebLink
WETLAND DEFINITION <br /> According to the t987 U.S. Army Corps of Engineers "Wetlands Delineation Nianual" (1937 <br /> Manual; the document used by all delineators to deFine wetlands) a tivetland is '`Those areas that <br /> are inundated or saturated by surface or ground water at a Frequency and duration sufficient to <br /> support, and that under normal circumstances do support, a preva(ence of vegetation typically <br /> adapted for life in saturated soil conditions." The Minnesota State Wetland Conservation Act <br /> Rules, Chapter 8�420, further clarifies that "...wetlands must: (1) have a predominance of hydric <br /> soils; (2) be inundated or saturated by surface water or groundwater at a frequency and duration <br /> sufticient to support a prevalence of hydrophytic vegetation typically adapted for life in saturated <br /> soil conditions; and (3) under normal circumstances, support a preva(ence of hydrophytic <br /> vegetation." The 1987 U.S. Army Corps of En�ineers Manual in Part [[, item 24. states that, <br /> "The interaction of hydrology, vegetation, and soil resu(ts in the development of characteristics <br /> unique to wetlands. Therefore, the following technical guidelines for wetlands are based on the <br /> three parameters, and diagnostic environmenta( characteristics used in applying the technical <br /> guideline are represented by various indicators of these parameters." It is this premise by which <br /> SER ecologists has, in their professional judgment, delineated the wetlands on the subject parce( <br /> described in this report. <br /> Wetland Hydrology <br /> The most important wetland criterion is hydrology. The peesence and persistence of water <br /> influences the vegetation types and changes soil morpho(ogy. Hydrology may be observed as <br /> standing water(inundation), or may be observed as freestanding water within the soi( pit or auger <br /> hole (saturation) usually within the upper 12 inches. This is what would be considered primary <br /> hydrology indicators. Only one primary indicator is necessary to make the determination that <br /> wetland hydro(ogy indeed exists. The 1987 Corps Manual a(so has a range of hydrologic zones <br /> established based on period of inundation or saturation. These zones and the periods of <br /> inundation or saturation for each can be obsecved in Table 1 below. <br /> Exce ted from the 1987 Manual, H drolo ic Zones—Nontidal Areas <br /> Zone Name Duration Comments Wetland or Not <br /> [ Permanently Inundated f 00°ro Inundation>6.6 ft. mean Not(Aquatic Habitat Zone, or Deep Water <br /> water de th Habitat) <br /> Semipermanently To Nearly ��� Inundation defined as <br /> [[ Permanently lnundated Or �100% �6.6 feet mean water Wetland <br /> Saturated de th <br /> ��� Re;ufarly Inundated Or >ZS-7�% <br /> Saturated Wetland <br /> IV Seasonally [nundated Or <12.�- <br /> Saturated 2j�/a Wetland <br /> [rre ularl [nundated or N[any areas havin�these <br /> V g Y >5-12.5% hydrolo�ic characteristics �'�etland(if hydrophytic veg.and hydric <br /> Saturated soifs also present <br /> are not wetlands <br /> [ntermittently Or Never Areas with these <br /> VI ►nundated Or Saturated �5% hydrologic characteristics Not <br /> are not wetlands <br /> A-1 <br />