“Don’t swim”: Lake Powell visitors warned as toxic algal blooms take over

Visitors to Glen Canyon National Recreation Area, home of Lake Powell, are being advised to exercise heightened caution this fall due to the presence of algal blooms in the water, with the National Park Service (NPS) issuing a warning about the potential health hazards these blooms pose.

Algal blooms, particularly harmful algal blooms (HABs), can produce dangerous toxins that threaten humans, pets and wildlife. These blooms thrive in warm, stagnant waters and are fueled by excess nutrients like nitrogen and phosphorus, often entering through runoff from surrounding areas.

While not all algae are harmful, HABs can pose serious health risks. Visitors to the recreation area are urged to be especially cautious around affected waters.

“HABs occur when normally occurring cyanobacteria in the water multiply quickly to form visible colonies or blooms,” the NPS said on its website.

Cyanobacteria, also known as “blue-green algae,” are found in bodies of water around the world. Their blooms are becoming increasingly frequent as nutrient runoff from fertilizers, detergents and other sources rises, according to the Environmental Protection Agency (EPA).

“These blooms sometimes produce potent cyanotoxins that pose serious health risks to humans and animals. Stay out of the water and avoid any contact with water or scums if you see pale-green or pea-green scum on or in the water and suspect a waterbody is experiencing a harmful algal bloom,” the NPS said.

HABs not only threaten local wildlife populations but can also harm humans, especially if toxins are ingested. Additionally, these toxins can accumulate in the tissues of fish and shellfish, indirectly affecting animals higher up the food chain, including humans.

Newsweek has contacted Glen Canyon National Recreation Area for an update on the situation via the media contact form on its website.

The NPS has outlined several key safety measures for visitors:

1. Don’t swim in waters with visible algal blooms.
2. Refrain from boating, water skiing, or jet-skiing on affected waters to prevent inhaling airborne toxins.
3. Keep children and pets away from scummy water or shorelines.
4. Always shower after contact with any surface water, regardless of visible algal presence.
5. Immediately rinse pets that have been in contact with potentially contaminated water.

The NPS also has a reporting system for potential HABs. Visitors who suspect a harmful algal bloom are encouraged to email glca_information@nps.gov with photos and GPS coordinates.

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