Chelan PUD Annual Reminder about Algae Blooms

by Kimberlee Craig | Jun 15, 2016

Annually, Chelan County PUD lets the public know about the potential for blue-green algae blooms in the Rock Island and Rocky Reach reservoirs when temperatures start to climb. High temperatures and reduced water levels can create an opportunity for the algae to form quickly. The PUD monitors the reservoirs to check for the presence of algae.

What are blue-green algae?
Blue-green algae are actually bacteria that have qualities similar to algae and other plants. The bacteria – cyanobacteria (cyan means “blue-green”) is commonly found on land and in lakes, rivers, ponds, estuaries and marine water.

What causes a blue-green algae bloom?
A combination of warm temperatures, sunlight and nutrient-rich water can cause rapidly forming blooms. The blooms usually float to the surface and can be several inches thick along the shoreline. It often looks like green paint floating on the water – but it also can look bluish, brownish or reddish-green. It is most common in the summer and fall, but can occur anytime.

Are blue-green algae dangerous?
Although blue-green blooms can create nuisance conditions and undesirable water quality, most are not toxic. However, some blue-green algae can produce toxins or poisons. In the toxic form, the blue-green algae can cause illness in humans, pets, waterfowl and other animals that come into contact with it. Toxic blooms can kill livestock and pets that drink the water.

How do you know if the algae are toxic?
Some ways to detect toxic levels of blue-green algae is if there are dead fish, waterfowl or other animals near a bloom area. Also, sudden, unexplained sickness or death of a cat or dog, especially if it has been around a blue-algae bloom area or the algae is on its mouth, legs or feet. Humans will notice a skin rash. In extreme cases, exposure can produce nerve and liver toxins resulting in numbness of the lips, tingling in fingers and toes, dizziness, abdominal pain, diarrhea and vomiting.


What if I see a bloom?
The best advice is to stay out or and away from the water that appears to have a blue-algae bloom. Assume the bloom is toxic and contact Chelan County Health District (509) 886-6400 or Chelan County PUD Parks Department at (509) 661-4551 or Marcie Steinmetz, PUD Water Resources specialist at (509) 661-4186.

For more information about Chelan County PUD’s response, contact Water Resource Specialist Marcie Steinmetz (509) 661-4186 or (509) 280-1955.

Visit the Washington State Department of Health’s website at

Outages or Emergencies

Visit our Safety and Outage Center for information, or to report an outage, 24 hours a day, 7 days a week, call 1-877-PUD-8123.


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