Current Toxic Algae Updates on the
Columbia River

Update:  September 27, 2024

Two recreational sites contained anatoxin-a BUT the levels were less than the recreational threshold (see below). 

In addition to Columbia River samples, a sample was taken from Scooteney Reservoir in Franklin Co. That sample contained very high levels of the toxin microcystin and Warning Signs have been posted there.

Sample Location

Sample Collection Date

Sample Analysis Date

Anatoxin-a (ppb)

Microcystins (ppb)

Howard Amon

09/23/24

09/27/24

0.116

<MDL

Columbia Park

09/23/24

09/27/24

0.357

<MDL

Scooteney Reservoir

09/24/24

09/27/24

<MDL

158

<MDL=Less than Minimum Detection Limit (Below what the instrument can reliably measure)

The state recreational threshold for Anatoxin-a is 1.0 ppb (ug/L)

The state recreational threshold for microcystin is 8.0 ppb (ug/L)

“Warning” signs are only posted when the state recreational threshold has been exceeded

All other sites that were tested were below the MDL.

We are now in the worst part of the algae season (Sept-Oct).  BFHD would like to remind users of the rivers to be cautious when swimming in the river and if green or brown material is floating on the surface, it is safest to stay out of the water. Dogs are most at risk as they have a tendency to ingest large amounts of water and also ingest algae material along the shoreline.

Next sampling event will be on October 7th.

BFHD Sampling Sites Map

Background
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. 

Is it safe to eat fish from rivers and lakes that have algae toxins in it? Click here to learn more.
 


BFHD always urges dog owners to be cautious when visiting a shoreline with your dog, follow these guidelines if your dog goes in the water: 

    • Do not let them eat or chew on clumps of algae
    •  Do not let them lick their fur
    •  Rinse them with clean water after swimming
    •  Rinse your hands and any exposed skin 

 

Animal Safety Graphic
Toxic Algae Warning Spanish

  

When in Doubt, Stay Out!

LEARN HOW BFHD TRACKED HARMFUL ALGAL BLOOMS
Full Recap BFHD Harmful Algae Bloom Season Recap (arcgis.com)
Visiting a Lake? Click on the picture to learn the Toxic Algae Status.
Washington State Toxic Algae Map
2024 Final Toxic Algae Poster
2024 Final Toxic Algae Poster
(Click photo to download pdf file)

Warning Signs to Watch For:
Yellow Warning Sign
Red Warning Sign