A massive vortex, big enough to suck in a full-sized boat, has appeared in Oklahoma's Lake Texoma.
Video footage of the whirlpool shows water draining at around 55,000 cubic metres of water every second.
Lake manager Joe Custer told WXII: "It's basically just a large whirlpool that's caused by the large gate openings, and all the water being evacuated through the gates.
"That's why we have the warning signs and buoy lines. People need to understand it's a very dangerous situation."
The water is being drained through two hydropower generators and floodgates. However, this year the lake reached its highest elevation in history – meaning the vortex is more pronounced.
The vortex is 8ft wide.
Custer said they will close the floodgates after the lake has drained back to more normal levels: "Once we're back within our flood control pool, under elevation 640, then we'll reduce the flow out of the floodgates so we can reduce the flooding downstream," he said.