Toxic algae detected in Kennewick’s Columbia Park. What dog owners need to know

Toxic algae has been detected at the family fishing pond at the east end of Columbia Park in Kennewick, posing a risk to dogs.

No swimming is allowed at the pond for humans and dogs, and signs are posted with that restriction.

Warning signs of toxic algae also have been posted around the pond by the Benton Franklin Health District and will remain until tests show the water is safe. The next samples of the water will be collected July 14.

Because a neurological toxin has been detected at unsafe levels, pet owners will need to be diligent about keeping their dogs away from the water.

Dogs are particularly susceptible to the toxin that was detected, anatoxin-a.

They may show symptoms as soon as 15 minutes after drinking water contaminated with the toxin, licking it off their wet fur or eating the algae.

Symptoms include weakness, staggering, having trouble breathing and seizures.

Symptoms in people include numbness around the mouth, tingling in fingers and toes, and dizziness. They should get medical help immediately.

In recent summers, nine dogs are known to have been sickened and some have died from ingesting the toxin and three others have been sickened from algae blooms in the Columbia River in the Tri-Cities area.

Water in the fishing pond comes from the nearby Columbia River.

Testing of Columbia River water, including the fishing pond, started this season on June 23, and the sample from the fishing pond collected then was later confirmed with an Environmental Protection Agency test to have toxins above safe levels for recreation.

Kennewick’s drinking water also was tested for the toxin and is safe, according to the city of Kennewick.

Toxic algae blooms are most common in the rivers in the Tri-Cities area from the second week of August, usually peaking in September and continuing into October.

The health district plans a public meeting to provide information on toxic algae in the Tri-Cities area at 7 p.m. July 8 at its office at 7102 W. Okanogan Place in Kennewick.

Jim Coleman, the climate effects specialist at the district, will answer questions and get tips on enjoying Tri-Cities rivers and waterways safely this summer, including tips to spot harmful algae.

The district’s test results and related information about toxic algae are posted at bit.ly/3FPiOAc.

This story was originally published July 4, 2025 at 9:40 AM.