WILLISTON, N.D. (KUMV) - A few days before the busy Labor Day weekend, the state is warning people about toxic algae at Williams County’s most popular recreation site.

The state Department of Environmental Quality says there are higher-than-normal levels of blue-green algae at Blacktail Dam. It can be toxic to humans and animals.

While not at critical levels, Williams County Parks Director Jeremy Ludlum says it’s important that children and pets stay away from areas where the water looks like spilled green paint or pea soup.

Blue-green algae tends to form when nutrients from fertilizers and septic systems seep into slow-moving water that gets a lot of sunlight.

Ludlum says the cooler nights accelerated the spread.

“When it cools off, that algae starts to die. When it dies, it releases

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