1. Wetland Delineation of a Selected Site within the Indian Rock Dam Reservoir Area near Codorus Creek in York, Pennsylvania INTRODUCTION Wetlands provide multiple benefits to the ecosystem and organisms which reside near them.  The conservation of wetlands is important, of the 215 million acres which once resided in the United States, only 99 million acres of wetlands remain.  Wetlands act as sieves or as a natural source of water purification, trapping impurities such as sediment or organic matter.  Wetlands also promote habitat growth and upkeep, they supply plants with nutrients and release vegetation into nearby rivers. This supplies aquatic life with food.  Flood prevention is another benefit of a wetland, as the soil retains much of the water and is able to release it slowly. (Tiner 1998)  The primary reason Indian Rock Dam was constructed is to redirect water into the Codorus Creek, preventing the York area from being flooded. CRITERIA Delineation of a wetland area requires that three specifications are met. This method has been accepted by prior leading wetland researchers.  Hydrophytic vegetation: Once vegetation has been identified, no less than 50% of the current vegetation must be either facultative wetland, facultative, or obligate.  Hydric soil: This may be found by checking that the soil chroma level is no more than 2. The soil must be taken from no more than 10 inches of the surface.  Hydric Indicators: Standing water, saturated soil, watermarks on trees and vegetation. Indicators can be visualized by examining the entire area. (U.S. Army Corps of Engineers 1987) OBJECTIVES To select a condensed location within Indian Rock Dam that will provide adequate results. An accurate determination will be made using the accepted criteria from previous wetland classifications. To properly delineate whether or not the location is considered a wetland. Colby Appel Department of Biological Sciences, York College of Pennsylvania METHODS A site was selected within the Indian Rock Dam Reservoir and GPS coordinates were mapped Three transects were created within the selected area, each transect would contain six holes Soil samples were taken at each hole at various depths Surface 18 inches 12 inches 6 inches Each soil sample was compared based on individual values/chromas recorded A Munsell soil color chart was used to conclude if hydric soil was present within the samples Vegetation surrounding the holes was identified Vegetative coverage of each hole was evaluated based upon the accepted criteria of at least 50% wetland Throughout the entire area any hydric indicators present would be evaluated by wetland standards RESULTS DISCUSSION Each site within the delineation area contained at least 2 of the required criteria for a wetland determination except for Transect one hole six. There were only two sites, transect one hole six and transect two hole six, which did not meet all requirements. In both cases these were the furthest holes away from Codorus Creek of their respective transects. Both outliers were on elevated plains and may have experienced a long decrease in water being received due to their elevation. This is considered to be an alteration of the surroundings, though it is natural it helps explain the change in hydrology. Many signs of flooding are present throughout the area such as standing water, vegetation which is covered in mud, and trees having swollen trunks. Decomposing plant matter was present on the soil. The soil also qualifies as a peat or muck. The site being evaluated qualifies to be a wetland. The few discrepancies can be explained using the guidelines found in the United States Army Corps of Engineers Wetland Delineation Manual. LITERATURE CITED Lanzara, P., Pizzetti, M., and Schuler, S. 1977. Simon and Schuster’s guide to trees. A field guide to conifers, palms, broadleaf’s, fruits, flowering trees, and trees of economic importance. Majumdar, S.K., Brooks, R.P., Bremer, F.J., and Tiner, R.W. 1989. Wetlands ecology and conservation. Emphasis in Pennsylvania. Pennsylvania academy of science. Tiner, R.W. 1987. A field guide to coastal wetland plants of the northeastern United States Tiner. R. W. 1998. In search of swampland. A wetland sourcebook and field guide. Rutgers University Press. New Brunswick, NJ U.S. Army Corps of Engineers. 1987. Environmental Laboratory. Wetland Delineation Manual Manual. Technical report y-89 U.S. Army Engineer Waterwaysexperiment I would like to thank Dr. Bruce Smith for his guidance and wisdom on this project. Table 2. Percent coverage of Vegetation at each hole. Table 1. Soil samples from the delineation area, analyzed using a 10YR Munsell Soil Color Chart. Common NameScientific Name Hydric Indica. Percent Coverage 0m Japanese Stiltgrass Microstegium vimineum (Trin.) Camus FAC80 Multiflora RoseRosa multiflora (L.)FACU5 F alse Stinging Nettle Boehmeria cylindrica (L.) SwartzFACW2.5 PA SmartweedPolygonum hydropiperoides Michx.OBL10 Silver MapleAcer saccharinum (L.)FACW- SpicebushLindera benzoin (L.) BlumeFACW-- Stinging NettleLaportia canadensis (L.)FACW2.5 Table 3. A Listing of Vegetation, hydric indication, and vegetative coverage at Indian Rock Dam found in the second transect. Transect Hole Number Soil Depth (Inches) Value/Chroma 061218 114/23/12/1 24/12/1 3/2 34/23/13/2 4 3/13/23/1 5 2/23/13/2 63/13/33/24/1 214/2 3/2 24/23/12/12/2 34/23/13/25/4 44/13/2 5/3 53/23/14/34/2 63/14/34/25/3 314/2 4/15/4 24/14/23/23/1 33/23/1 2/1 44/2 3/25/3 53/23/13/22/2 63/23/12/22/1 Hydrophytic Vegetation (Percent coverage) Transect # 0ft60 ft120 ft180 ft240 ft300 ft 168.352.666.443.699.432.1 295.046.299.278.582.662.9 3100 98.395.294.698.7 Figure 1. Muddy vegetation found pressed together from a large amount of water at site. Figure 2. Stinging Nettle ( Boehmeria cylindrica) which has been covered by mud from flood waters. Figure 3. Standing water found all around the selected area.