10/21/2026
Geneva Lake Environmental Association (GLEA) confirmed a potentially harmful blue-green algae bloom moving along the shoreline of Williams Bay. The bloom has appeared intermittently across areas in Williams Bay and continues to move depending on wind and environmental conditions.
People and pets should avoid entering the lake where water appears discolored, has โstreakingโ green, or looks to have โsurface scumโ. Advisory signs have been posted at the lakefront. Use caution when entering the water, blooms can move with changing wind and water conditions.
Wisconsin Department of Health reminds us โ When in doubt, stay out! Further guidance regarding blue-green algae includes:
โข Do not swim or wade through algal scums.
โข Do not boat, water ski, or jet ski through algal blooms.
โข Do not fish in lakes where algal scum is present.
โข Always shower off with soap and water after swimming in a lake.
If you spot a suspected algae bloom, contact GLEA at 262.683.2067.
If youโve come in contact or have further questions about an algae reach out to Walworth County Public Health at 262.741.3200 - [email protected].
For more information about blue-green algae, blooms and resources, check out these helpful links.
https://www.co.walworth.wi.us/425/Beach-Water-Quality
https://www.dhs.wisconsin.gov/algae/index.htm
http://dnr.wisconsin.gov/topic/lakes/bluegreenalgae