Cyanobacteria, also known as blue-green algae, are bacteria which have some of the characteristics of plants. They are found throughout the world on land and in lakes, rivers, and ponds, and in estuaries and seawater (oceans).  Thought to be caused in part by global warming, all over the world, more and more water bodies are seeing large areas of growth or algae blooms.  These blooms are important because the bacteria produce toxins that affect water quality, ecosystem stability, surface drinking water supplies and public health.  

During early fall of 2021, portions of the shores of the Columbia River that flow through the Tri-Cities area (Richland, Kennewick and Pasco) were closed after the deaths of several dogs who had been exposed to toxic algae while along the shoreline.   

In Benton and Franklin Counties, BFHD was aware of this issue occurring in local lakes and rivers.  What made this incident in 2021 unique was that toxin-producing blooms had not been found in the flowing waters of the Columbia River.  Of concern was that the area in which the blooms appeared to be occurring was the same area where the cities of Richland, Kennewick and Pasco have water intakes for their drinking water treatment facilities.  BFHD works closely with these utilities to make sure that the drinking water is safe.

While not all algae blooms produce toxins, but there is no easy or quick way to know if a bloom contains harmful toxins.  Activities that can expose you to toxic algae are swimming, boating or fishing.  During these activities, exposure to toxic algae typically occurs when the toxins are swallowed, or one inhales water spray with the toxins.  By far, swallowing is the most common way to be exposed. 

Current Advisories: 
Update: November 4, 2022

The Warning signs have been taken down on the Columbia River shoreline from the Leslie Groves Park boat launch at Snyder to the boat launch at Columbia Point.

 Toxin levels were detectable at Leslie Groves, but they were below the state threshold level (below 1 ug/L) and have been for the last two weeks. 


No other sites are showing levels of concern.

BFHD Water Lab will be testing the Columbia River sites again on the 14th and 28th of November. Those will be the last samples of 2022, unless higher levels are detected.

When in Doubt, Stay Out!

Visiting a Lake? Click on the picture to learn the Toxic Algae Status.
Washington State Toxic Algae Map
Toxic Algae Poster