Pennsylvania’s Compensatory Wetland Mitigation: Analysis of Selected Sites in Southern York County. Vince Marechal, and Bruce Smith Department of Biological Sciences, York College of Pennsylvania INTRODUCTION Wetlands are important for many reasons including water filtration, floodwater storage, erosion control, and providing recreational areas. Wetlands also provide a habitat for nearly one third of the plant and animal species listed by the Federal government as endangered or threatened and provide nesting areas for over 50% of the nation’s migratory bird population. The United States once had an estimated 215 million acres of wetlands. Wetlands decreased from M A to M A from 1970’s through the 1980’s (Dahl and Johnson 1991, Bunkley and Edmonds 1992). In 1972, the Federal Water Pollution Control Act (FWPCA) was passed by congress to “restore and maintain the chemical, physical, and biological integrity” of the Nation’s waters. Amended in 1977, the FWPCA came to be known as the Clean Water Act (CWA). Recent reports by the U.S. Fish and Wildlife Service still indicate a loss of 1,000 acres of wetlands per year (Dahl, 2000). In 1990, the EPA and the FWS entered into a memorandum of agreement (MOA). The MOA provided a “mitigation sequencing” to conform to the national objective of “no net loss” (Edmonds 1997). Per the 1990 MOA, Wetland Creation is one of three forms of compensatory mitigation. Mitigation ratios such as Indiana’s required minimum 1:1.8 ratio are intended to compensate for the time the wetland was no longer functional to the time the mitigated wetland is mature and also to compensate for the risk that the mitigation will be a failure (Robb 2002). OBJECTIVE With some wetland loss being unavoidable, such as erosion of tidal wetlands, it is of utmost importance to ensure that the mitigation process, which has evolved over the years, is working properly in replacing the wetlands which man destroys. The purposes of this study are to: (1) analyze two local mitigation projects and (2) quantify success or failure of Pennsylvania’s mitigation ratios. METHODS The design for this research was a modification of the methods Robb used in his assessment of wetland compensatory mitigation sites in Indiana (Robb 2002). Two sites, one in Hanover, PA and the other in Dover, PA, were selected for analysis. Each wetland was redelineated using the methods outlined in the Field Guide for Wetland Delineation: 1987 Corps of Engineers Manual and Field Guide to Nontidal Wetland Identification (WTI 1999). The area of each wetland was calculated using a global positioning system, Corpscon 5.X®, and Eagle Point AutoCAD®. Random quadrat sampling was done at each site to complete the vegetative analysis using transects along the perimeter and random number tables. All plants falling within the quadrats were counted and identified using Field Guide to Nontidal Wetland Identification (Tiner 1988). The standing water depths were measured at the center of each quadrat. Two soil samples were taken for identification. Observed wildlife was documented. The Hanover site was subdivided into two separate communities: (1) Cattail, and (2) Herbaceous for the random quadrat vegetative sampling. Figure 2. Hanover PA, Cattail Community: total species sampled v. total quadrats sampled Figure 1. Hanover PA, Herbaceous Community: total species sampled v. total quadrats sampled Figure 3. Dover PA (A): total species sampled v. total quadrats sampled Figure 4. Dover PA (B): total species sampled v. total quadrats sampled DISCUSSION / CONCLUSION Additional research is needed to draw any solid conclusions. Results of this study suggest a net loss of Pennsylvania wetlands. Similar studies covering the entire state are recommended. Should results from future studies be similar to those from this study, Pennsylvania should consider revising its minimum 1:1 mitigation ratio to one larger in order to compensate for failure rates. Pennsylvania should also consider replacement of wetlands with wetlands that have identical functions. Palustrine Emergent Marsh (PEM) replacement with Palustrine Open Water (POW) or any combination of POW and PEM should therefore cease to be permitted. Literature Cited Bunkley, W. and Edmonds III, C.P Appraising wetlands. Appraisal Journal V60:1 page107 Dahl, T.E. and C.E. Johnson Status and trends of wetlands in the conterminous United States, Mid-1970’s to Mid-1980’s. U.S. Department of the Interior, Fish and Wildlife Service, Washington D.C. 28 pp. Edmonds, C.E., Keating, D.M., and Stanwick, S Wetland mitigation. Appraisal Journal v65:1page72(5) Robb, J.T Assessing Wetland Compensatory Mitigation Sites To Aid In Establishing Mitigation Ratios Wetlands v22:2 page 435(5) Tiner JR., R.W Field Guide to Nontidal Wetland Identification. Maryland Department of Natural Resources, Annapolis MD and U.S. Fish and Wildlife Service, Newton Corner, MA. Cooperative publication. 283 pp. Wetland Training Institute, Inc. (WTI) Field Guide for Wetland Delineation: 1987 Corps of Engineers Manual. Glenwood, NM. WTI pp. RESULTS Dover Site Hanover Site Vegetation Dover replaced more m 2 than was destroyed but was still short of the required area for mitagation. Hanover was short on the required mitigation and in replacing what was destroyed (Table 1). In comparing the herbaceous species at both sites, despite having a significant species mortality, Dover had a greater Shannon- Weaver Index indicating greater species diversity (Table 2). Soils The soil sample results did not reveal hydric soils, however the soils were of lower chroma than the standard for these soil types* * Dover A 5YR 4/2, Dover B 5YR 2.5/2: Hanover 10YR 5/4 and 2.5Y 4/3. Wildlife Evidence of the following were observed at both sites: white tail deer, raccoon, snails, frogs, canadian geese, and red wing black birds Acknowledgements Dr. Bruce Smith of York College of Pennsylvania, Fred Gabriel of First Capital Engineering, Kelly Heffner of PA DEP, and Dr. Karl Kleiner of York College of Pennsylvania