Algae Control Program photo

Algae Control Program


In 2005, the Washington State Legislature established funding for an algae control program and asked the Washington Department of Ecology (Ecology) to develop the program. Reducing nutrient input to lakes is the only long-term solution to prevent algae blooms. However the amount of money available for this program (about $250,000 per year) is not enough to fund comprehensive lake-wide and watershed-wide nutrient reduction projects. Instead the program focuses on providing local governments with the tools they need to manage algae problems. The program targets blue-green algae (also known as cyanobacteria) because these algae pose a health risk to humans, pets, and livestock.

  • Ecology's algae program provides for:
    • Algae identification.
    • Toxicity testing (microcystin, anatoxin-a, cylindrospermopsin, and saxitoxin).
    • An on-line database to post the laboratory results.
    • Small grants (up to $50,000) for algae or nutrient management projects (see the latest funding list)

Aquatic Algae Control Program Legislative Reports

Ecology began funding small grants to local governments in fall 2007 (see the funding list). The Washington Department of Health (DOH) has developed statewide recreational guidelines for cyanobacterial toxins (microcystin , anatoxin-a, cylindrospermopsin, and saxitoxin)  under a grant provided by Ecology. These guidelines will help local governments make decisions about when to post health advisories and when to close waters to recreation. DOH has also developed educational signs and outreach materials about algal blooms. 

Join Ecology's Freshwater Algae Program List Serve

Ecology has set up a list serve for freshwater algae. If you would like to receive toxicity reports about freshwater algae blooms go to

What is an Algae Bloom?

Many Washington lakes and even some rivers have problems with excessive growth of algae. Algae can be smelly and unsightly as well as being toxic to humans, pets, and livestock. Algae grow rapidly when sunlight, temperature, and nutrients are adequate. Within only a few days, a clear lake can become cloudy with algae. When an algal species reproduces rapidly and reaches high concentrations, it is called an algae bloom. The nutrients phosphorus and nitrogen are found in animal and human waste (sewage), in fertilizers, and even in rainwater. Too much phosphorus and nitrogen lead to nutrient rich water bodies. Nutrient-enrichment leads to algae blooms.

There are many types of algae. Most are harmless, some are considered nuisances, and others are important to lake productivity. Blue-green algae are actually bacteria called cyanobacteria. They can create problems when they form blooms. The blooms happen mostly in the summer or fall, but can occur anytime. Blue-green blooms may float to the surface and can be several inches thick near the shoreline. A blue-green algae bloom often looks like green paint floating on the water and is hard to pick up or hold.

Why is Ecology particularly concerned about blue-green algae?

Blue-green algae blooms pose a human health concern and have killed pets and livestock. Although most blue-green blooms are not toxic, some blue-green algae produce nervous system or liver toxins. Toxicity is hard to predict. A single species of algae can have toxic and non-toxic strains. A bloom that tests non-toxic one day can become toxic the next day.

People may become ill after swimming or water skiing in lakes with toxic blue-green algae. Human health effects may include stomach pains, vomiting, diarrhea, skin rashes, and nerve and liver damage. Pets and wildlife have died after exposure to toxic blue-green algae in Washington lakes. Blue-green blooms affect lake recreation creating economic losses.

How can you get more information about the algae program?

Read more about algae, their impacts, grants, and control options by clicking on the navigation links on the left side of the screen. You may also contact the following people directly for more information about the algae program.

Banner photograph courtesy of professional photographer Bruce Andre at