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For Release: Monday, October 17, 2022

DEC Celebrates Success of Croton River Invasive Species Control Project

Croton River Treated and Monitored for Invasive Hydrilla for Six Seasons, No Hydrilla Found in 2022

The New York State Department of Environmental Conservation (DEC) today announced the successful completion of a long-term treatment of the aquatic invasive plant Hydrilla verticillata in the Croton River. Federally listed and State prohibited hydrilla was first discovered in the Croton River in 2013. Nine years later, no hydrilla was found thanks to an intensive DEC control project.

"The Croton River Hydrilla Control Project was the first large-scale aquatic invasive plant control effort managed by DEC," said DEC Commissioner Basil Seggos. "Hydrilla grows and spreads quickly and can be one of the most difficult aquatic invasive plants to control. Infestations can have negative impacts on recreation and tourism and pose severe consequences for aquatic ecosystems. DEC is proud of the success of these treatments and grateful to our partners for their work to protect the Croton and Hudson rivers from hydrilla."

The Croton River is a large and direct tributary to the Hudson River. It is an important recreational fishery, popular destination for swimming and paddling, and the source of drinking water for the village of Croton.

Hydrilla is a federally listed noxious weed and a prohibited plant under State invasive species regulations. It can rapidly spread and form dense mats of vegetation that impact access to the river and displace native plants and animals that would typically use the river for food and shelter. In addition, decomposition of hydrilla biomass can impact drinking water quality.

Over several years, DEC engaged in extensive planning for this eradication project, including stakeholder meetings, pilot studies, and extensive aquatic plant surveying which culminated in the development of a five-year management plan of hydrilla in the Croton River. This effort has proven successful in preserving the Croton River and its uses, as well as protecting the Hudson River Estuary and its unique habitats.

Beginning in 2017, the project used aquatic herbicide to treat and control hydrilla. Prior to treatment, hydrilla was found at 190 of 446 aquatic plant survey points within the Croton River. In 2022, no hydrilla was found at any of these same 446 survey points. The control project also surveyed and documented that no hydrilla has been found in the Hudson River. In total, hydrilla in the Croton River has been treated and monitored for six seasons and with key collaboration by the village of Croton-on-Hudson, New York City Department of Environmental Protection (NYCDEP), Riverkeeper, and Westchester County Parks. DEC will continue to monitor the river for an additional three years starting in 2023.

DEC invested a total of more than $3.5 million from the State Environmental Protection Fund (EPF) for the multi-year project. The EPF is a critical resource for environmental programs such as land acquisition, farmland protection, invasive species prevention and eradication, recreation access, water quality improvement, and environmental justice projects. Among the many environmental victories in the 2022-23 State Budget (leaves DEC website), Governor Hochul succeeded in increasing the EPF from $300 to $400 million, the highest-ever level of funding in the program's history. This year, the EPF has $17 million dedicated to invasives species management in New York State.

To learn more about the Croton River Hydrilla Control Project, visit DEC's project webpage. Simple steps to stop the spread of aquatic invasive species can be found on DEC's website. For more information about hydrilla, visit DEC's website.

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