Hydrilla USGS
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Dredging in Cayuga Inlet

Dredging in the Cayuga Inlet is long overdue and necessary for navigation of the waterfront to continue. Dredging sediment that contains hydrilla often causes concern about spreading the invasive weed to surrounding areas. Fortunately, the new introduction of geotubes to the Cayuga Inlet dredging project has reduced this concern.

According to a report from NYSDEC, the dredge spoils will be pumped into large sleeves of permeable fabric known as geotubes. Geotubes will contain hydrilla fragments and turions, thus preventing them from spreading elsewhere. Geotubes allow for easier filtering of dredged material from water, reducing the area required for dewatering and allowing for greater production rates in dredging. 

Dredging in the Cayuga Inlet will deepen the channel by 1 to 2 feet. The design for the project is still in the making, but NYSDEC anticipates the plans to be completed by the end of 2016 to allow for actual dredging in 2017.

Sedimentation in the Cayuga Inlet is a naturally recurring process. Due to human activity over the past century, this process has been slightly increased and the need for dredging has arisen in order to allow for human navigation of the waterfront. The 2011 dredging effort was the first one since the inlet was last dredged in 1982, but was halted at the discovery of hydrilla. Hydraulic dredging, which is being planned for 2017, is a vacuum process that mixes water with the material, allowing it to be pumped out into large geotubes and sent to a dewatering site before the plant and soil mixture is reused beneficially elsewhere. 

For a complete assessment of this process and analysis of its effectiveness in the Inlet, see Assessment of Diver-Assisted Dredging

Last updated January 6, 2020