Kansas health officials say three of the state’s lakes are under health warnings because of high levels of toxic blue-green algae blooms.

The Kansas Department of Health and Environment said in a statement that the lakes under warning aren’t closed, but that contact with the water can cause serious illness and should be avoided.

KDHE says elevated algae levels have been found in Hiawatha City Lake in Brown County, Marion Reservoir in Marion County, and Plainville Township Lake in Rooks County.

KDHE says the water should never be consumed by humans, pets or livestock.