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Algal Bloom Water Contact Advisory Lifted for Lake Waterford

Last updated: November 12, 2019

Department of Health Lifts Harmful Algal Bloom Water Contact Advisory for Lake Waterford in Pasadena

October 16, 2019 – The Anne Arundel County Department of Health has lifted the harmful algal bloom advisory against direct water contact for Lake Waterford in Pasadena. The Maryland Department of the Environment reported the latest microcystin level for Lake Waterford is 2.0 ppb (parts per billion), which is significantly below the state water contact advisory threshold of 10 ppb. The advisory had been issued on July 3, 2019.

The blooms of blue-green algae reported at Lake Waterford naturally occur in fresh waters and in Maryland’s Chesapeake Bay. The blooms are in nutrient rich environments and can become harmful when they occur in high concentrations or when they produce toxins.

When bathers see bright green waters, sometimes with a surface scum that resembles green paint, they are advised to take the following precautions:

  • Do not wade, swim or drink in areas where a blue-green algal bloom is evident.
  • If contact is unavoidable, wash body and clothes with clean, warm soapy water.
  • If there is skin irritation after contact, see a health care provider.
  • Keep pets away from bloom areas. Pets should not ingest or come in contact with water during a bloom. Questions regarding any suspected symptoms in pets should be directed to a veterinarian.
  • Some blue-green algal toxins may accumulate in fish and crabs, primarily in the internal organs such as the liver and kidneys, or the mustard in crabs. Although anyone eating fish or shellfish containing harmful algal bloom toxins may become ill, people with some chronic diseases, such as liver disease, could potentially have very severe illnesses.
  • If you decide to eat fish caught from waters affected by a blue-green algal bloom, remove the fat, skin and organs before cooking. Be careful not to cut into the organs. Before cooking or freezing the fish, rinse the fillets with clean water to remove any contaminants from the cleaning process. Cook fish thoroughly.

More information about blooms can be found on the Maryland Department of Natural Resources website: To report human illness from bloom water contact, call the Bay Health Hotline at 877- 224-4229.

For up-to-date information about water contact advisories, visit the Department of Health’s website at Subscribers to the Department’s Recreational Water Quality Email Alerts receive emails notifying them of county waterway advisories, closings and re-openings. To sign up for the free e-alerts, visit Alerts can also be received by following the Department on Twitter at

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