Be on the lookout for algal blooms in Arizona

Harmful algae were reported this month at Tonto National Forest, and park rangers are advising people visiting lakes to avoid contact with the water, as it could be poisonous.

Here’s what you need to know and how to stay safe.

What are harmful algae?

According to the Arizona Department of Environmental Quality, algae are a normal part of aquatic ecosystems and can be found in all types of water. But when these microscopic organisms grow out of control, which is called a “bloom,” they can release a toxic substance that can cause serious illnesses and can even be deadly in rare cases.

The two most common algal blooms in Arizona are blue-green and golden algae. Blue-green algal blooms produce toxins or poisons that can make people and pets sick upon contact with the water, and they can be particularly dangerous for children, according to the Tonto National Forest.

A bloom of golden algae can kill fish populations, according to ADEQ, but experts don’t know with certainty if it is harmful to humans or other animals. However, the department advised people to not ingest the water or eat fish that were in water impacted by a golden algae bloom.

Where are algal blooms in Arizona?

This summer, blue-green algal blooms have been spotted at Tonto National Forest and Bartlett Reservoir Lake in Cave Creek, but you can easily identify if the water has an algal bloom by the way it looks.

According to the ADEQ, water with harmful blue-green algae can have the following appearance:

● Look like pea soup or spilled green paint

● Discolor or leave streaks in the water

● Be surface scum, mats or films

● Appear as green dots or globs floating below the surface

How do I stay safe?

The department advised people to stay away from algae and scum in the water and to be particularly aware of keeping children and pets away from the shore, where algae can also accumulate.

The national forest also advised people to never drink or use the water for cooking, and if you’re unsure whether the water contains an algal bloom or not, stay out and do not touch the water. Boating and fishing are acceptable, according to the forest, but ingesting or being in contact with the water can be harmful.

The ADEQ asked the public to report possible harmful algal blooms. If you see one around Arizona, you can contact the local land owner or manager of the waterbody, file a report through the Arizona Water Watch mobile app or contact the department at truitt.rebecca@azdeq.gov.

Fish kills and golden algae blooms can be reported to the Arizona Game and Fish Department.