Wetland Classification/ident/delineation-2007

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, , No one has ever undertaken a scientific stud to evaluate the relations ' between the Y �P , hydrological requirerrients and the presence of various wetland or non-wetland plant species. This is a critical, yet unanswered question. Some studies have been completed examining so� types and hydrological responsrveness but the lmk between plants and hydrology has yet to be , made. Given the annual cost of jurisdictional decisions in terms of "lost land" opportunities, perhaps such a study would be prudent. , The in�plications of regulatory misinterpretation are enormous in that it is l�cely that hundreds of acres of Type 1 wetlands are avoided or mitigated for each year when legitnnately these areas are non�unsdictional and could be developed. , Avoidance or mzpact and mitigation can cost developers and ultunately, homebuyers, millions of dollars annually just in the developing seven-county Metropolitan Area. Mitigating a non- ' jurisdictional Type 1 wetland impact at a 2:1 ratio reduces the usable land base wm�essan7y. For every 50 acres of non jurisdictional in�pact, 100 acres are removed from the land supply. At an average cost of $100,000 per acre, the cost to developers and ultimately to homeowners is ' $10,000,000 in just onc yeaz for just 50 acres. Type 2/3 � Type 3 wetlands create the greatest classification dif�culty from the perspective of de minimus qualification. A Type 3 wetland thai is seasonally flooded (C) is typically characterized by reed canary grass whereas a Type 3 semi-permanently flooded wetland is more I�cely characterized ' by a growth of catta�7s. The reed canary wetlands are generally dry by late spring to early suYrm�r. By late sunnner, the water tables have receded to well below the surface (> 18 — 36"). In contrast, Type 3 cattai7 wetlands st�l contain water above or very near the surface during , normal growing seasons. The WCA permits the use of de minimus filling of Types 1, 2, 6 and 7 wetlands. Clearly it is not ' the nrtem of the WCA to allow the application of the de minimus criteria to fens since the WCA specifically addresses fens as a special category for protection. Therefore, the Type 2 designation rrwst gpply to the "C": modifier Type 3 wetlamd Further, Type 3 wetlands m excess of 2.5 acres , in incorporated areas and in excess of 10 a�cres in unincorporated areas are protected under the DNR protected waters statute. In the DNR wetland inventory and classification process,the Type 3 wetlands were clearly dommated by cattaz7s hence the inference that reed canary grass ' wetlands were Type 2. Type 7/Type 1 L ' Inconsistencies in technical descriptions regarding the hydrological regime of these two wetland types from a scientific perspective become only a matter of discussion between scientists. However, when wetland types are applied from a regulatory perspective, accuracy in definition , becomes crucial because certain activities may be permitted in one wetland type and prohibited in another. At present, Wetland Types 1L and 7 are subject to the same wetland regulatory ' requirerrients and exceptions. However, that may not be always the case and therefore it is importaat to note the crucial yet subtle di�erences between the two types. � The majority of bottomland floodplain forests in many years have water tables several feet 5wboda Ecological Resow�ces 2180 Abingdon Way Project No.2007-056-03 Orono,Minnesota �