Frequently Asked Questions

GCHD relies on the public to notify us if they see blooms of Blue-Green Algae in waterbodies in Grant County. If you want to report a harmful algae bloom anywhere in Grant County, you can email pictures to us.  Please include when and where the photos were taken. When a harmful algae bloom (HAB) is verified, we take samples of the bloom.  GCHD staff can take samples or we can coordinate sampling with CSCUM. 

CSCUM stands for Cyanobacteria Surveillance by Citizens, Users, and Managers. It is a citizen group coordinated by GCHD for the purpose of monitoring Blue-Green algae. Samples are collected on Mondays or Tuesdays and sent out for testing at the King County Environmental Laboratory. The samples are shipped out the same day they are taken and we usually have results by Friday. All results are posted on this page when we get them (see table in Observations and Advisories Section). If results from sampling show that toxin levels are above the Washington Department of Health's Recreational Guidance Levels, GCHD will post advisory signs along the waterbody at public access areas such as swim beaches and boat launches, as well as updating information on our webpage. GCHD may also notify the public through media releases and social media. The advisory won't be lifted until 2 consecutive samples show toxin levels are below the guidance levels.

As soon as you see a bloom or possible signs of exposure:

• Avoid all contact with the water.
• Keep pets and livestock away from the water.
• Call the Grant County Health District at 509-766-7960 and report the location.