Rapid growth of the algae, known as a “bloom,” can produce toxic chemicals that may make people and pets sick. Young children, the elderly and people with compromised immune systems are especially at risk. Symptoms include rashes, vomiting, diarrhea and wheezing.
Officials say people should avoid contact with water that is discolored, has green-colored streaks, looks like spilled paint or has surface scums or greenish blobs beneath the surface.
Activities near the water, such as hiking or camping, aren’t affected.