The Vermont Department of Fish and Wildlife is warning people not to use parts of the Poultney and Hubbardton rivers in West Haven today.
The department issued the advisory because technicians plan to treat the rivers today with chemicals to kill immature sea lampreys.
The advisory is for the lower Hubbardton River, below the falls off River Road in West Haven and for the Poultney River between the Carver Falls Dam and the outlet of South Bay, near Whitehall, New York.
The department advises against using stream or lake water in these areas for drinking, swimming, fishing, livestock watering or irrigation while these restrictions.
The restrictions will last from 10 to 15 days.
Sea lamprey are parasites that can kill fish like trout and salmon.