Expect to see some increased activity in the downtown Jamestown area over the next several weeks as the Chautauqua Watershed Conservancy, together with the Chautauqua County Soil and Water Conservation District, will be addressing severe bank erosion issues in the Chadakoin River basin and along the bank sections of the Chadakoin River between the Warner Dam and Main Street bridge.
Over the past few years, we have been monitoring the undercutting that is taking place along the shoreline of the Chadakoin River basin below the train station. This bank section is subject to the hydrological impacts from the Warner Dam’s opening and closing. Downtown riverbanks consist mostly of historic fill material which is not stable and has been eroding away for many decades. In addition, the water level in the basin is purposefully maintained at the exact same level each summer because the Warner Dam helps set the desired Chautauqua Lake level. This has caused the north shore of the basin to be undercut by more than two feet in places. This area is now critically unstable and could collapse at any time. This risk is exacerbated by the poor health of the trees along the shore, which are impacted by the same hydrological challenges (water exposing/undercutting/damaging their roots). All of the trees lining the shore below the train station are currently dead, dying, or of an undesirable species for the location (e.g., the Black Locust, which is rapidly causing new problems for the City’s park’s department). These trees are now at risk of falling into the basin, which would cause significant and highly visible damage to the banks and trigger costly repairs if dealt with reactively.
Through an ARPA allocation from the City of Jamestown to the Chautauqua Watershed Conservancy, we are able to pre-emptively remove all compromised trees and rebuild the banks using sustainable “living shoreline” principles, similar to those applied to the basin’s opposite shore in 2017-18. This will create a beautiful and resilient long-term solution for the lingering challenges that this area has been facing for a very long time. These bank restoration efforts will also form the literal foundation for any future development and activation initiatives that are being planned for the basin area.
Downstream from the Warner Dam, hydrological action of dam-released water similarly erodes away low-lying banks and causes sediment loss, negative impacts on water quality, and an ongoing need for costly repairs. Water damage and, more recently, beaver damage has led to the near total loss of trees along the section of the Chadakoin River between the Warner Dam and the North Main Street bridge. Regular flooding at the lowest points (near the Main Street bridge) has rendered this section of the riverwalk unusable for recreational activities (and potentially dangerous due to the risk of people falling in the river because of unstable banks). Here, too, we will remove compromised trees and rebuild the banks using a combination of stacked rocks and native shoreline vegetation to form a beautiful and resilient natural-looking shoreline.
Apart from providing increased bank stability, these restoration efforts will also greatly improve the aesthetic “curb appeal” of the downtown area and publicly accessible Riverwalk. In addition, they will result in critical improvements to the health and environmental quality of the Chadakoin River and its downstream watershed. Runoff from approximately 150 acres of lawn and impervious urban surface (streets, parking lots, etc.) enters the river after each rainstorm through the areas we’re improving. The new living shorelines will allow storm water to infiltrate, and their vegetation will help filter sediment and pollutants, thus improving the river’s water quality and fish habitat.
The loss of the existing trees along the project area may be a jarring sight in the short term, but once the newly restored banks are planted next spring, and new trees are added, we can all enjoy watching the downtown area come alive in new ways!
photo and article by Twan Leenders, Chautauqua Watershed Conservancy Director of Conservation
Top photo: A section of the Chadakoin River basin shows severe undercutting of its bank and a precarious condition of bank trees. Work will soon begin to restore the bank, building it out to the edge of the exposed shelf to create a sloping design that allows for birds, turtles, and other wildlife to readily enter and exit the basin.
Additional site photos:
Above - the north shore of the Chadakoin River section below the Warner Dam. Note the supersaturated soil and wrack line of pine needles (blue arrows) that indicate recent water levels. Regular flooding softens this bank and causes sediment loss and erosion, which is routinely patched when sections collapse.
Below - An example of ongoing spot repairs throughout the proposed project areas. Note the proximity of the Riverwalk and the high visibility of these costly and unsustainable patches.