Completed Wetlands Maps of Tompkins County Available — 2016
Nicholas Hollingshead’s completed 2015 wetlands maps of Tompkins County are available for viewing and use at DropBox.
Hollingshead is working with Cornell digital librarians to provide access via CUGIR (Cornell University Geospatial Information Repository).
Hollingshead’s final project report to Tompkins County (2/16) “Wetlands Mapping and Protection for Tompkins County” may be viewed as a downloadable file to the right. Also available is the 2014 Dryden pilot project final report from 2014.
THANK YOU to the Park Foundation, Tompkins County Legislature, and to Nick Hollingshead for this great project.
The Network’s goal is to help our other watershed counties get their wetlands mapping updated.
“Like sponges, wetlands soak up and store the stormwater from rainstorms and melting snow. This protects downstream lands from flooding, and recharges groundwater. Stormwater is released gradually, slowing water’s erosive power. Wetlands are often referred to as the kidneys of nature, because they trap and store sediment that carries pollutants. The unique soils and plant communities found in wetlands are filters, improving downstream water quality.”
New Study to Map Wetlands Across Tompkins County — 2015
During 2014, Nick Hollingshead mapped the Town of Dryden’s wetlands using LiDar data (elevation data created from aircraft overflying the land) and GIS software, significantly improving accuracy over the older computer-generated wetland maps created decades ago by NY’s Department of Conservation and the federal US Fish and Wildlife Service. The state and federal maps tend to significantly underestimate the number and extent of wetlands, often completely missing smaller wetlands.
In 2015 Nick is expanding the study, using the LiDar method to re-map the wetlands of Tompkins County. Again sponsored by the Cayuga Lake Watershed Network (CLWN), Hollingshead’s work is supported by a generous grant from the Park Foundation and additional support from the Tompkins County legislature. The initial Dryden study was funded by the Tompkins County Soil and Water Conservation District via the Finger Lakes – Lake Ontario Watershed Protection Alliance, and in-kind match from several sources.
The main objectives of this project are to develop an accurate and current map of wetlands in Tompkins County; and deliver this new resource to local municipalities, providing support for the use of the data gathered, and encouraging adoption of local wetland-specific regulations. The ultimate goal is to protect local water quality and conserve the unique ecological services that wetlands provide.
Science advisors for this work are John Mawdsley of the CLWN’s Board and Darby Kiley, Town of Ulysses planner, both members of the Wetlands Committee of the Tompkins County Water Resources Council along with Dooley Kiefer and Tom Vawter. The initial impetus for this project came from a 2008 wetlands mapping review by the committee, which found that the available state and federal wetlands maps lack accuracy and coverage.
Wetlands: losses, values, functions
Across the United States, it is estimated that over 100 million acres of wetlands have been lost due to draining and filling. In New York State, over half of the historic wetlands have been converted for agriculture, development, and other uses. Impacts from these losses are evidenced by changes in runoff that increase the frequency and severity of flooding and sedimentation in streams and lakes. The conversion of wetlands for new development in rural areas has implications for local and downstream water quality and quantity. Additionally, climate change is bringing extreme storms that concentrate rain and snowfall into large, heavy-precipitation events. Wetland buffers are needed.
Wetlands provide a broad range of environmental benefits including nutrient uptake, floodwater retention, erosion reduction, and unique wildlife habitat. Often located between upland and aquatic areas, wetlands are also found in the many places where hydric soil (permanently or seasonally saturated by water, resulting in anaerobic conditions) supports specially adapted plant and animal communities. In the Finger Lakes region of New York, the diversity of wetland types include vernal pools, bogs, seeps, fens, marshes, river and stream edges, forested swamps, and wet meadows.
Like sponges, wetlands soak up and store the stormwater from rainstorms and melting snow. This protects downstream lands from flooding, and recharges groundwater. Stormwater is released gradually, slowing water’s erosive power. Wetlands are often referred to as the kidneys of nature, because they trap and store sediment that carries pollutants. The unique soils and plant communities found in wetlands are filters, improving downstream water quality.
On a warm, damp spring evening in many parts of Tompkins County, you are greeted by a chorus of frog songs. Amphibians are just one example of life that is dependent on wetlands for survival. A variety of bird and mammal species also depend on wetlands for food and shelter, as provided by the plants that grow there and nowhere else.
Better wetlands protection is needed
As in most of New York State, in Tompkins County there are currently no local wetland-specific regulations to fill the regulatory gaps left by state and federal laws. A 2008 study entitled Wetland Protections in Tompkins County: Existing Status, Gaps, and Future Needs found that up to 19% of the wetlands in Tompkins County have no protection based on existing state and federal regulations. This study was funded by a Wetland Program Development Grant from the EPA, administered by the Tompkins County Soil and Water Conservation District, and overseen by the Tompkins County Water Resources Council (WRC) Wetlands Committee. In response to the findings of this study, the WRC Wetlands Committee developed a sample wetlands protection local law, approved by the WRC in 2012 and presented to municipalities for adoption.
For effective implementation of local wetland protection laws or other municipal regulations, such as site plan reviews or stormwater plans, accurate wetland maps are essential. The present wetland maps from the New York State Department of Environmental Conservation and the U.S. Fish and Wildlife Service are based primarily on visual interpretation of aerial imagery collected in the 1980s. These are outdated, incomplete, and inaccurate, particularly for the types of wetlands not protected under state and federal laws.
Nick Hollinghead is updating these older maps. The visual analysis of high-resolution aerial imagery remains the most viable method for efficiently mapping wetlands across large areas, such as a town, county, or larger area. Improved aerial imagery and remote sensing data, including high resolution elevation data (LiDAR) and georeferenced oblique aerial imagery, make it possible to achieve higher levels of accuracy, completeness, and detail in less time. Of particular importance for the local wetland regulations is the potential to use these modern resources to identify small wetlands, such as vernal pools, that were not previously mapped.
- View the final report for the 2014 Dryden pilot study by clicking on the pdf to the right.
- The reference map for the Dryden study can also be viewed to the right.
- If you would like to view a particular map, have questions about a location or digital data, please contact Nicholas Hollingshead at firstname.lastname@example.org.