- Lake Powell is experiencing harmful algae blooms, with cyanotoxins at high exposure levels.
- Officials advise caution, telling people to avoid blue-green algae areas and rinse off after contact.
- Lake Powell water levels are also 26 feet below last year's July peak.
PAGE, Ariz. — Lake Powell's lower water levels aren't the only concern this Fourth of July weekend.
The concentration of cyanotoxins was found to be at the "high end of safe exposure levels" in the Antelope Canyon portion of the reservoir, which straddles the Utah-Arizona border, according to Glen Canyon National Recreation Area officials, who warned visitors on Wednesday.
Cyanotoxins are produced through harmful algal blooms and can be dangerous to humans and animals.
"The National Park Service recommends boaters use caution and avoid unnecessary exposure to reservoir water if fishing, boating or recreating in this area of Lake Powell. Other areas of Lake Powell may also contain these toxins; please use caution," officials added in a statement.
Harmful algal blooms typically form when warm and still water mixes with nitrogen and phosphorus that enter a body of water from outside sources, park officials explain. Blooms are common throughout Utah and Arizona, especially during the summer.
Park officials advise that visitors avoid any algae areas with a blue-green appearance, as that's typically what a harmful bloom looks like — although it can also form in different colors. They advise visitors not to swim or operate any watercraft in those sections, as it can also cause the toxins to become airborne, potentially leading to illness.
Children and pets should be kept away from algal blooms. People are encouraged to shower or rinse off pets as quickly as possible after coming into contact with any potential harmful algal bloom to avoid illness.
Anglers should discard all fish guts and skin, and only eat the fillet after thoroughly rinsing the meat, Utah environmental officials add.
Symptoms of exposure include nausea, vomiting, digestive distress, breathing problems, seizure or unexplained illness. These symptoms can range in severity but may lead to serious illness, per the Centers for Disease Control and Prevention. A dog died and three others became ill from a bloom in the Virgin River in Washington County that formed in 2023.
Lake Powell is a popular summer destination. Nearly 600,000 visitors came to the Glen Canyon National Recreation Area last July. And while year-over-year visitation patterns are trending downward this year, the area still attracted nearly 375,000 visitors in May.
The drop in visitors is also likely tied to the reservoir's lower levels, as it didn't benefit much from the latest snowpack. It's now at about 3,561 feet elevation, which is 26 feet below its peak in July 2024.
That's created other challenges, such as ramps that are inoperable for some types of vessels or all watercraft.
The following ramps are available for all boaters:
- Antelope Point Business Ramp
- Bullfrog North Launch Ramp
- Halls Crossing Launch Ramp
- Rainbow Bridge National Monument
These launch areas are partially available to boaters in July:
- Antelope Point Public Launch
- Bullfrog Main Launch
- Wahweap Main Launch
- Wahweap Stateline Auxiliary Launch
