Annual Elimination of Water Chestnuts in the Seneca River

The Onondaga County Health Department will begin to reduce the number of water chestnuts in the Seneca River in the Baldwinsville and Three Rivers areas beginning Monday, July 25 through Friday, July 29, 2016.  Water chestnuts are plants that are rooted in the river bottom. Water chestnuts spread quickly and their seeds can remain dormant for several years making elimination of water chestnuts a multi-year effort.  Due to its thick formation, water chestnuts hinder navigation, crowd native plants, and reduce fish habitat.

The primary herbicide that will be used for this purpose is Clearcast (active ingredient: imazamox). Rodeo (active ingredient:  glyphosate) will also be used. Clearcast and Rodeo are considered safe for the control of vegetation in and around natural bodies of water and non-cropland sites. However, Clearcast and Rodeo are harmful if absorbed through the skin or inhaled and can cause moderate eye irritation. As a precautionary measure, we are asking the public to avoid the areas while they are being treated. Signs will be posted to identify the treated areas. Detailed descriptions and maps of the treatment areas are available at:

For more information about the pesticides that will be used, please visit: