Environmental Health
Surface Water (Lakes, Rivers & Streams)
Swimming in Thurston County

No advisories in effect for Thurston County lakes.

Summit Lake Blue-Green Algae

On May 13, 2014, a lake water sample with blue-green algae in it was delivered to our office by a lake resident. The sample was sent to King County Environmental Lab to test for algae toxins. The result showed the presence of the toxin Anatoxin at a concentration slightly above the health advisory level of 1 ug/L (part per billion). Anatoxin is a potent neurotoxin produced by a few species of blue-green algae.

After consulting with Washington Department of Health, county health staff collected additional lake water samples from multiple sites around the lake and from two drinking water taps on May 21, 2014. Anatoxin was present in all of the samples, but in very low amounts that were all well below the health advisory level. The sample locations and results are attached. 

Click Here for Results

As a follow up, another 4 samples were collected May 28, 2014 and sent for analysis. County Health Department staff will continue to sample the lake weekly; until the algae toxin is no longer detected.

See resources below for more information.

Summit Lake Community Meeting

On Thursday, June 5, 2014 a regularly scheduled Summit Lake homeowners meeting was held. Staff from the Health Department were invited to attended the meeting to provide information and answer questions property owners may have regarding blue-green algae blooms and Anatoxin levels found in water samples taken by a Summit Lake volunteer and county staff. Click here for the list of questions and answers. [PDF]

Volunteer for Lake Watch

Thurston County is looking for volunteers to help "watch" local lakes for algae blooms. Volunteer activities may include:

  • Contacting us when you see an algae bloom.
  • Taking samples and delivering them to the Health Department on Lilly Road.
  • Posting warning signs.
  • Distributing toxic algae alerts to your neighbors.

To become a Lake Watch Volunteer, you can either print, fill out and send us the attached sign up form (click link) or you can enter your information and submit the form electronically.

Other Information

News & Info
  • Report algae blooms or swimming-related illness
  • General Questions
This page last updated: 07/13/16