identifying wetland mitigation sites using gis

INTRODUCTION:

Determine if GIS can be used to successfully identify potential wetland mitigation sites in Tioga County.

Provide potential solution to update National Wetland Inventory in Tioga County, Pennsylvania by accurately identifying highly likely wetland areas.

Wetlands act as filters(excess nutrients, sediment, and chemicals)

Wetlands provide flood protection(hold large amounts of water and release it slowly)

Wetlands provide habitat and breeding ground to a wide variety of organisms

Migratory birds rely on wetlands to provide natural protective cover and food

Home to many endangered and threatened species

INTRODUCTION:

Section 404 of the Clean Water Act program to regulate the discharge of dredged or fill material into waters of the United States, including wetlands.

INTRODUCTION:

Those areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal conditions do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs and similar areas.

(US Army Corps of Engineers)

Pennsylvania uses the Federal Regulatory Definition for wetland permitting as follows:

BACKGROUND:

Hydric SoilSoil that develops certain characteristics from being saturated for several weeks.

Hydrophytic VegetationVegetation that thrives in wetland conditions

HydrologyWater either from ground or surface sources

BACKGROUND:

U.S. Fish and Wildlife Service’s National Wetland Inventory

Data was collected in the 1980’s using remote sensing data from the 1970’s

Method used to collect data utilized high-altitude aerial photos and was then supplemented by field investigations

Because of Federal Regulations at the time, Agricultural Land was not included in the Wetland Inventory.

PURPOSE:

In the last 20 years, since the Inventory data was mapped, Tioga County has undergone a lot of growth and change.(new highways, and development that change hydrologic flow)

Much of the Agricultural land not included in the Inventory has now been developed anyway.

Natural changes over time

Natural gas development permitting

Updating is recommended in order to continue to provide regulated protection to sensitive wetland areas. (flood protection, water quality, and habitat)

PURPOSE:

Data: HAP (High Alleghany Plateau) –Aquatic Hydric Soils (Natural Lands Trust, 2010)

Data Reclassified as:

25 – Hydric

0 – Non-Hydric.

DATA & ANALYSIS:

To calculate Hydrology two sets of data were used:

Percent Slope

Distance from Streams

DATA & ANALYSIS:

Data: National Elevation Dataset for Pennsylvania (U.S. Geological Survey (USGS),

EROS Data Center, 1999)

Surface Analysis-Slope was used to calculate Percent Slope

Data Reclassified into 5 classifications as follows:

0%-5% slope = 256%-15% slope = 2016%-25% slope = 1526%-50% slope = 1051%-145% slope = 5

DATA & ANALYSIS:

Data: PAMAP - Hydrography (PAMAP Program, PA

Department of Conservation and Natural Resources, Bureau of Topographic and Geologic Survey, 2007)

3,000 foot buffer distance from streams

Spatial Analysis – Distance – Straight Line

Distance from streams data was reclassified and given scores as follows:

0 – 200 feet = 25201 – 500 feet = 20501 – 1,000 feet = 151,001 – 1,500 feet = 101,501 – 3,000 feet = 5

DATA & ANALYSIS:

Data: HAP (High Alleghany Plateau) - Terrestrial Natural Vegetation (Natural Lands Trust)

Data Reclassified into 5 categories

Given a score from 0-25 as follows:

Barren/Highly Developed/Urban = 5Light Developed/Lawn/Cropland =10Forest (mixed, conifer, deciduous) /Pasture =15Vegetation (scrub/shrub/grassland) =20Classified Wetland Vegetation =25

DATA & ANALYSIS:

DATA & ANALYSIS:

Calculation:Soil + Percent Slope + Distance From Streams + Vegetation

Result:Score of 20 - 100

GCS North American 1983 Data Acquired From:Pennsylvania Spatial Data Access, US Census Bureau, Natural Lands Trust, PAMAP Program, PA Department of Conservation and Natural Resources, Bureau of Topographic and Geologic Survey, and U.S. Geological Survey (USGS), EROS Data Center

RESULTS:

Reclassified:

20 – 55

60 – 80

85 - 100

RESULTS:

Overlaying the results of this study with the already classified NWI wetland data indicates that the data used and the methods were successful in finding wetland areas in Tioga County

Further Investigation is required to determine if other potential sites indicated in this study meet the requirements to be classified as wetlands.

• Gray, Ayesha, Robert P. Brooks, Denice Heller Wardrop, and Jennifer K. Perot. "Student Manual for Pennsylvania's Adopt-a-Wetland Program." Penn State Department of Geography. Penn State Cooperative Wetland Center, n.d. Web. 6 Apr 2011. <http://old.geog.psu.edu/wetlands/manual/toc.html#top>.

• "Tioga County." Tioga County, Pennsylvania. Tioga County Courthouse, n.d. Web. 6 Apr 2011. <http://www.tiogacountypa.us/Pages/default.aspx>.

• "Wetland Regulation Center." Wetlands.com. US Army Corps of Engineers, 2005. Web. 6 Apr 2011. <http://www.wetlands.com>.

• W., Ralph. Wetland Indicators: A Guide to Wetland Identification, Delineation, Classification, and Mapping. Boca Raton: CRC, 1999. Print.