A vortex up to eight feet wide was recently caught on camera at a lake in Oklahoma when officials opened the gates to a nearby dam.

The dam was opened to drain the overflowing Lake Texoma, which created the vortex. Assistant project manager BJ Parkey told ABC News it’s similar to what happens in a bathtub. 

“I always compare it to when you fill up your bathtub and then pull the plug. When the water level gets low enough, you’ll see an apparent vortex,” Parkey told the station.

“Obviously we don’t have a plug like that in the dam, but the concept is the same,” he added.

Whenever officials drain the lake, a similar vortex has formed but not always to this size. The most recent vortex is reportedly large enough to swallow a boat, prompting park rangers to set up buoys and warning signs for boaters in the vicinity. Officials decided to drain the lake after four weeks of heavy rains created flooding.

In Oregon, a similar phenomena occurs at Lost Lake only it is created by natural causes each spring and the water drains into a volcanic lava tube. 

Photo credit: Youtube screenshot