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Cl�r��icatfl�n �f ���vard�n C�ass�cat��� <br /> .;, . <br /> an� C'i�°c�afl�r 39 <br /> ���Il��� �y��s �y ��y .�y � ��� / <br /> By <br /> Franl:lin J.:Svoboda <br /> � Svohocla Ecological Resoucces � <br /> 2477 Shadywood Road,.Suite 100 <br /> Excelsior,MN 55331 <br /> (952)471-1100 <br /> franks@gpsinnovafions:com <br /> Introductaon <br /> The National Wetland.:Inventory (NWn mapping process completed in 1Vlinnesota between 1979 <br /> and 1982 developed a wetlands inventory map for the state of.Minnesota utilizing remotely <br /> sensed color infrared photography that was visually interpreted. The interpretation process <br /> hierarchically classified wetlands using; at the time, ihe recently published .Cowardin <br /> classi�cation system(Cowardin et al "1979). The we�land interpretafion and classification process <br /> ' was ground verifed using selective plots and locations but was field verified to :only a limited <br /> extent, Conseguently, fhe published NWI paper copies carry the disclaimer.that these maps are to <br /> be used for .advzsor.y purposes only and actual classifications_ are to be based on groand <br /> verification. Visual interpretation from remote sensed imagery has some limitations particularly <br /> with regard to the water regime modif er.�Year to year variafion in precipitation cycles. along <br /> wifh the occurrence of precipitatio.n events:at the time that the imagery was acquired, even if all <br /> acquisition occurred during the spring season,can;result in vaziations in modifier categorization. <br /> Aceurate classification becomes critical wfien regulatory decisions are being.made with regard xo <br /> the wedand .type and the :amount of de mininaum f 11 that is permissible. Also, it is a matter of <br /> scientifically accurate consistency with regazd :to adherence to the various .technical•publications <br /> and regulaeory guidance documents. � • <br /> Circulaz 39 was authored by Shaw and Fredine and published by the U. S. Fish and WildTife <br /> Service (USFWS) in 1956. The intended purpose of Circular 39 was an effort at classifying and <br /> inventorying wetlands on. a national scale in order to assess the wetland 'base and related <br /> waterfowl production potential. T.he classification process was never intended to serve as a <br /> classif'ication systeni for wetland �'egulatory pucposes. However, since.it was the first national <br /> effort of its kind and as wetland regulatory intentions materialized, this was .the only.method. <br /> a�lailable to differentiate between ��etlands of different types. . <br /> The Board of Vdater and Soil Resources (BWSR) cross-reference table (8420.0549 subp. 2.) <br /> indicates fhat Cir.cular '39 Type 3 v�letlands have a `'C" water regime modifier. This is an <br /> f <br />