Lake Berryessa's 'Glory Hole' Spillway Reopens After Heavy Rainfall, Drawing Crowds and Raising Safety Concerns

The Breathtaking Return of Lake Berryessa’s ‘Glory Hole’

When the Lake Berryessa reservoir topped 15 feet after relentless rainfall, something wild and a little scary happened: a gaping 75-foot-wide vortex sprang to life, leaving visitors both stunned and a tad rattled. Locals have long nicknamed this bizarre swirl the 'Glory Hole,' and when it opens, things get intense—especially for water fans and viral video seekers.

The science behind this so-called ‘Glory Hole’ is both simple and huge. Engineers in the 1950s built this massive concrete drain—think of it like a gigantic outdoor bathtub plug—at the Monticello Dam to stop the reservoir from flooding. When the lake fills to the brim, instead of spilling over, it all gets sucked through a 200-foot-deep spillway carved into the landscape. During those rare times, this thing inhales 48,000 cubic feet of water per second. That’s enough to fill a backyard pool faster than you can blink.

The real-life sight of all that water spinning into the earth is a hypnotic mix of beautiful and terrifying, the kind of thing you might see in a sci-fi movie. People rush to social media to share photos and videos, calling it everything from 'majestic' to 'nightmare fuel.' Last time it put on this watery show was in 2017 and 2019 when rains came hard and fast—until now. Weather folks might say the last downpours weren’t unexpected, but nobody can resist gaping at that perfect circle of churning water when it appears.

Danger Below the Surface—And Remembering the Risks

No surprise, there’s more to this spectacle than viral hype. It’s got a deadly history, too. In 1997, Emily Schwalek lost her life after being sucked down while swimming too close to the spillway, a reminder that as cool as this natural marvel looks, it’s no joke. Since then, authorities snapped into action—strict no-swimming, no-boating rules, and plenty of newly beefed-up safety barriers keep adrenaline junkies and oblivious tourists from getting too close. California’s solvers don’t play around, especially with plenty of people snapping selfies a little closer than they should.

Most of the action now happens from a safer distance. There’s a concrete overlook at the southeastern edge of the slim finger of lake—far enough away, but close enough to hear the rush and see the water vanish. Kids, parents, hikers, and the rare helmeted cyclist show up, standing in awe. All told, when Lake Berryessa hits its full 52 billion gallons, locals know to keep an eye out. People will drive for miles just to say they saw the Glory Hole in action—even if it’s just for a day or two until the water drops.

After every activation, a fresh reel of new social media clips appears. Some shoot the vortex at sunrise for that sci-fi glow, others zoom in close and let the swirling current fill the screen. But underneath the tidal excitement, there’s always that unspoken knowledge: as beautiful as California’s big artificial 'maw' can be, there’s a fierce and unpredictable side to these rare, powerful moments at the heart of Lake Berryessa.