The Department of Environmental Quality (DEQ), in cooperation with the Department of Natural and Cultural Resources, City of Durham, Durham County, Town of Hillsborough and Orange County will be treating the Eno River for Hydrilla May 15, 2023 through August 31, 2023.
Hydrilla is a submerged aquatic species originally from Asia. The invasive plant was first discovered in the Eno River Watershed’s Lake Orange in the early 1990s. It can create nearly impenetrable mats of stems and leaves in lakes, rivers, and other waterways, impeding recreational use. It also affects native vegetation and can harm fish and other aquatic and bird species.
The treatment area is located just below the Ben Johnson Lake dam and continues along the river to the U.S. Highway 501 crossing in Durham. The herbicide is applied using a two-injection system to meter the appropriate amount of herbicide throughout the treatment area. It is used at a concentration well within limits approved by the US Environmental Protection Agency – determined safe for swimmers and boaters and non-toxic to fish and wildlife. For additional information on water quality safety during the treatment period, contact the N.C. Department of Health and Human Services at (919) 707-5900.
The Eno River Hydrilla Management Task Force first introduced the herbicide fluridone in 2015 to a 16-mile treatment zone largely within Eno River State Park in Orange and Durham counties. It was the first time the herbicide was used successfully in a river in North Carolina to combat hydrilla, although it has been used for many years elsewhere in large lakes.
The Eno River Hydrilla Management Task Force comprises federal, state, and local government representatives, including staff from North Carolina State Parks, the N.C. Division of Water Resources Aquatic Weed Control Program and the N.C. Wildlife Resources Commission. The group has been working since 2007 to evaluate and address the hydrilla threat in the Eno River.
For more information, visit the DEQ website’s Eno River Hydrilla Management Project page, or contact Drew Gay, Aquatic Weed Specialist, Division of Water Resources at 919 707-9020 or email andrew.gay@ncdenr.gov. NCDHHS offers a fact sheet on health effects of Hydrilla treatment.