Wetland Mitigation Monitoring Report - McWilliams SiteWetland Mitigation Monitoring Report - McWilliams SiteChristopher Bevan Miller, Department of Biology, York College

Wetlands are home to various unique and rare species of plants and animals.

When a wetland is destroyed by man, a replacement “in-kind” wetland must be created – this is referred to as a mitigation site.

For five years after the mitigation site is created, the mitigation site must be monitored using a process referred to as a wetland delineation.

There are several methods for performing a wetland delineation; they are comprised of three main facets, an evaluation of the soil, hydrology, and the vegetation on the site.

All three components must fulfill the requirements of a wetland to be deemed a wetland.

The McWilliams site, the site of my study, was a wetland mitigation created due to a wetland being destroyed to build a parking lot for access to a rail trail.

Introduction

Research Question

How does a created wetland with installed How does a created wetland with installed vegetation progress or regress from its initial vegetation progress or regress from its initial state in terms of vegetation, soil and hydrology?state in terms of vegetation, soil and hydrology?

Results

Methods

•Divide plot into transectsDivide plot into transects RandomRandom Setup pin flags at 41 pointsSetup pin flags at 41 points

•Determine what vegetation exist at each pin flagDetermine what vegetation exist at each pin flag Use 1m PVC pipe square aligned to NorthUse 1m PVC pipe square aligned to North Determine what plants are in the square and theirDetermine what plants are in the square and their aerial coverageaerial coverage•SoilSoil

6 points evenly spread throughout plot6 points evenly spread throughout plot Ground, 12”, and 18” depthsGround, 12”, and 18” depths

•HydrologyHydrology Basic hydrology info at all pin flagsBasic hydrology info at all pin flags

Key References

Munsell Color. 1975. Munsell Color. 1975. Munsell Soil Color charts.Munsell Soil Color charts. Munsell Color, Macbeth Division of Kollmorgen Munsell Color, Macbeth Division of Kollmorgen Corp., Baltimore, MD.Corp., Baltimore, MD.Soil Survey of York County, Pennsylvania. 1967 May. United States Department of Agriculture, Soil Survey of York County, Pennsylvania. 1967 May. United States Department of Agriculture, Soil Conservation Service, in Cooperation with Pennsylvania State University College of Soil Conservation Service, in Cooperation with Pennsylvania State University College of Agriculture and Experiment Station and Pennsylvania Department of Agriculture, State Soil Agriculture and Experiment Station and Pennsylvania Department of Agriculture, State Soil Conservation Commission.Conservation Commission.Tiner, R.W., 1988, Field Guide to Nontidal Wetland Identification. Maryland Department of Tiner, R.W., 1988, Field Guide to Nontidal Wetland Identification. Maryland Department of Natural Resources, Annapolis, MD and US Fish and Wildlife Service, Newton Corner, MA. Natural Resources, Annapolis, MD and US Fish and Wildlife Service, Newton Corner, MA. Cooperative publication. 283pp.+plates.Cooperative publication. 283pp.+plates.Tiner, R.W., 1990. Pennsylvania’s Wetland: Current States and Recent Trends. US Fish and Tiner, R.W., 1990. Pennsylvania’s Wetland: Current States and Recent Trends. US Fish and Wildlife Service, Newton Corner, MA. 104pp.Wildlife Service, Newton Corner, MA. 104pp.

Acknowledgements

I thank Mr. Thomas Stich for his advice on fine tuning my project and providing me with countless hours of help in the field. I would also thank Dr. Bruce Smith for providing a path for me to complete this project and his abundant wealth on the subject.

2000 2001 2002 2003 2004 2005 2006 20070

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OBL to FACWFACFAC- to UPL

Yearly Percent Aerial Coverage for Various Species Classes

Figure 1. Percent aerial coverage for the six years data was collected. Plantsfound in the OBL to FACW class are found greater than 66% of the time in awetland. Plants in the FAC class are found 50% of the time in wetland. Plantsin the FAC- to UPL are found less than 33% of the time in a wetland.

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Percent Species that are Wetland versus Upland

2000 2001 2002 2003 2004 2005 2006 20070

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Wetland SpeciesUpland Species

Figure 2. Percentage of either wetland species or upland speices aredepicted in this graph. Total wetland species was divided by the totalspecies in the plot.

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The total percent aerial coverage of three different classes of plants is shown in Figure 1; those found greater than 66% of the time in a wetland (OBL to FACW), those found 50% of the time in a wetland (FAC) and those found less than 33% of the time in a wetland (FAC- to UPL). The total aerial coverage of the obligate wetland to facultative wetland species is increasing from the initial date in 2001. This is an indicator that the wetland/mitigation site is progressing.The percentage of plants in the mitigation site that are normally found 50% of the time or more often in a wetland is depicted in Figure 2. For a site to be deemed a wetland, the percentage of species that range from a facultative species to an obligate wetland species (found greater than 50% of the time in a wetland) must comprise over 50% of the total species in the transect. Over the past seven years there is a trend of the mitigation site becoming more wetland plant dominant.The soils of the wetland are currently a silt loam with Munsell Color Chart data of 10YR for all locations tested, a color ranging from 2-4, and a value ranging from 3-4. The layers of soil now exhibit characteristics of a hydric soil that were not present in the first few years after creation of the mitigation site. The soil had several rust colored streaks which are oxidized soil (the iron is leeching out) and some of the roots are oxidized. These are both indicators of hydric conditions and saturated anaerobic conditions. Also a small amount of decayed organic matter was seen.There are two large areas of year round free standing water on the mitigation site. At most transect points where vegetation data was collected, the ground was moist even after weeks without rain. When soil data was collected at a depth of twelve inches, water immediately, after removing the soil, began to fill the pit.

Conclusion

The McWilliams mitigation site is progressing in terms of becoming more of a wetland over the years of 2001 until 2007 even after substantial flooding, the worst draught in fifty years and four wheelers ripping up the site in 2002-2003. The percent aerial coverage of wetland specific species has increased and the percent aerial coverage of upland species has decreased over the seven years. The percent of total species that were wetland specific species has also increased over this time frame. During the course of the seven years over ten species of wetland plants have volunteered onto the site. The soil is slowly beginning to exhibit more hydric conditions and this change would be more prevalent over the course of thirty years as opposed to seven years. The hydrology was not truly tested in any of the seven years, but it still exists and fits the COE guide for being a wetland.