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Hydrilla Treatment in the Croton River to Begin on July 5, 2017
Village of Croton-on-Hudson E-Notice

The New York State Department of Environmental Conservation (NYSDEC) will begin its herbicide treatment of the hydrilla infestation in the Croton River on July 5th 2017. Treatment is likely to continue until mid-October 2017. The application of the aquatic herbicide fluridone (Sonar Genesis) is intended to control the growth and spread of the highly invasive aquatic plant hydrilla and reduce the plant’s long-term impacts on recreation, ecology, and water quality in the Croton River. NYSDEC has chosen a method of control that allows for use of a low concentration of herbicide (2-4 parts per billion) that is well below NYS Department of Health and US Environmental Protection Agency (EPA) recommended limits. To put the treatment plan in perspective, the acceptable potable water limit per New York State Department of Health is 50 parts per billion. The concentration will be carefully monitored at the Village of Croton drinking water wells and in the river itself throughout the treatment period. Updates about drinking water sample results will be posted on the project webpage along with many other project details, which members of the public may access here: Please note that Silver Lake will remain open and there will be no restrictions on swimming as the treatment will not pose a risk to public health. Signage with information about the Hydrilla treatment will be placed along the Croton River in both English and Spanish.

This treatment program is the culmination of a long process, which included various meetings and public information sessions between the Village Board, Water Control Commission, Waterfront Advisory Committee, NYS Department of Environmental Conservation (NYSDEC) and NYC Department of Environmental Protection (NYCDEP). Hydrilla poses a grave threat to the health and viability of the Croton River and beyond, and the NYSDEC’s treatment will help to ensure that this aquatic invasive plant species does not populate further along the Croton River.

What is Hydrilla?

Hydrilla verticillata is a freshwater~plant with~stems that can grow up to 25 feet long. The plant branches out horizontally at the water's surface and creates dense mats. Hydrilla has small, pointed, serrated leaves arranged around the stem, typically in whorls of five.~Hydrilla grows quickly and creates~dense mats that can block out sunlight and harm native plants, and its density can also kill fish by decreasing oxygen levels.~

Hydrilla is native to Australia,~Asia~and Africa and is believed to have made its way to the U.S. as an aquarium plant.

Hydrilla is often spread by boaters, as hydrilla fragments can cling to boats and trailers. Very small fragments of hydrilla can start new populations.