Monticello Dam is a foot 93 m high concrete arch dam in Napa County, California , United States , constructed between and Lake Berryessa is currently the seventh-largest man-made lake in California. Water from the reservoir primarily supplies agriculture in the Sacramento Valley downstream. The dam is noted for its classic, uncontrolled morning-glory-type spillway.
The Glory Hole at Lake Berryessa
The spectacular 'Glory Hole' spillway in Monticello Dam, California
At 22 meters in diameter, the hole sucks in water from the dam to prevent flooding at a rate of 1, cubic meters per second when it reaches capacity, according to Atlas Obscura. The water is carried through a large concrete pipe and emptied about meters away. The hole has been cordoned off for safety reasons since when a woman was pulled in and drowned. During the dry season, when the exit of the spillway is visible, skateboarders have been known to use it as a ramp — although this isn't recommended. Otherwise, boats and swimmers cannot get too close. The Glory Hole was built between and , and wasn't constructed to overspill regularly. In fact, it wasn't expected to be in use much more than once every 50 years.
A very active glory hole pic by Eric. The Monticello Dam , which holds back Lake Berryessa , features a morning glory spillway. This type of spillway is basically a giant cement funnel. Rather than spilling over the dam, high waters spill into the funnel.
Federal Health Minister Greg Hunt says the medical regulator has approved the Pfizer vaccine for children aged 12 to Follow our live coverage for the latest news on the coronavirus pandemic. The massive Morning Glory Spillway in the Lake Berryessa reservoir in northern California was originally designed to funnel away water after unusually big storms, and was only expected to flow a couple of times per century when heavy rains filled the lake to capacity. But recent dramatic video and photographs show the circular spillway, known by locals more colourfully as the "glory hole", flowing for the second time in two years, after the brimming lake became too big for its banks.