Frequently Asked Questions

There are 3 kinds of signs GCHD posts for harmful algae blooms:

• There is an informational sign that may be posted at waterbodies that have a history of blue-green algae blooms.  These signs stay up year-round even, if when there are no harmful algae blooms on the lake.
• The first advisory sign is a Warning Sign.  Warning signs are posted when sampling results show the algae bloom has toxin levels above recreational guidelines. This means the water is unsafe for people and pets and you should avoid contact with the lake including swimming, wading, skiing, or tubing.
• The second advisory sign is a Danger Sign. Danger signs are posted when GCHD gets confirmed reports of people getting sick from cyanobacteria toxins. Danger signs will also be posted if there is a confirmed report of the death of a pet. Danger signs mean the lake is closed to all recreation.