The Upper Pamunkey Branch, Terry’s Run, and the Upper North Anna Branch of Lake Anna in Orange, Louisa and Spotsylvania counties are experiencing a harmful algae bloom (HAB). The public is advised to avoid contact with the lake in these areas until algae concentrations return to acceptable levels. Some harmful algae, called cyanobacteria, can cause skin rash and gastrointestinal illnesses, such as upset stomach, nausea, vomiting and diarrhea. The areas to avoid can be seen on an interactive map at www.SwimHealthyVA.com.
Results of samples collected at sites within these areas contained potentially harmful algae (cyanobacteria) which exceed safe swimming levels. People and pets are advised to avoid swimming, windsurfing and stand-up-paddle-boarding as well as other activities that pose a risk of ingesting water or exposure to skin. Advisory signs will be posted in areas of the lake.
There is routine monitoring occurring above Route 208 on Lake Anna. On July 15, 2020, samples collected at three sites indicated swimming advisories were necessary. These sites correspond to:
Pamunkey Branch
- Upper – From the upper inundated waters of the Pamunkey arm of the lake downstream to the confluence with Terry’s Run
- Terrys Run – from the upper inundated waters of the lake downstream to the confluence with Pamunkey Creek
North Anna Branch
- Upper – From the upper inundated waters of the North Anna arm of the lake downstream to the Route 522 Bridge.
Algae blooms can occur when warm water and nutrients combine to make conditions favorable for algae growth. Most algae species are harmless, however some species may produce irritating compounds or toxins. Avoid discolored water or scums that are green or blueish-green because they are more likely to contain toxins.
To prevent illness, people should:
- Avoid contact with any area of the lake where water is green or an advisory sign is posted,
WHEN IN DOUBT, STAY OUT!
- Do not allow children or pets to drink from natural bodies of water.
- Keep children and pets out of the areas experiencing a harmful algae bloom and quickly wash them off with plenty of fresh, clean water after coming into contact with algae scum or bloom water.
- If you or your animals experience symptoms after swimming in or near an algal bloom, seek medical/veterinarian care.
- To ensure fish fillets are safe to eat, properly clean fish by removing skin and discarding all internal organs, and cooking fish to the proper temperature.
- If you suspect you experienced health-related effects following exposure to a bloom, contact the Virginia Harmful Algal Bloom Hotline at 1-888-238-6154.
- To learn more about harmful algae blooms or to report an algae bloom or fish kill visit www.SwimHealthyVA.com.
The Virginia Department of Health and the Virginia Harmful Algal Bloom Task Force, which includes the Virginia Department of Health, Virginia Department of Environmental Quality, and the Old Dominion Phytoplankton lab, will continue to monitor water quality in the lake. In general, advisories will be lifted following two consecutive test results with acceptable levels for algal cell counts and/or toxin concentration. An advisory may be lifted or maintained at the discretion of the health department. For example, after one test an advisory may be lifted if results are below safe levels for swimming if other information indicates exposure or human health risk is low.
