The World’s Largest Drain
Here in Lake Berryessa, California, we find the largest drain hole in the world, affectionally known locally as The Glory Hole.
Narrowing from 22 metres diameter to 8.5 metres at its thinnest point, this absolutely enormous funnel is technically the largest “morning glory spillway” in the world – an uncontrolled outlet which, should the water level rise sufficiently high, allows up to 1370 m³ per second (48,400 cubic feet) of water to bypass the Monticello Dam. Check out this photo of the spillway in full flow.
The spillway’s horizontal exit is on the southern side of the dam, and this ground level shot demonstrates why this is a popular spot for local skateboarders and bikers during the drier months!
Read more about spillways, the Monticello Dam and Lake Berryessa at Wikipedia, and trophybassonly.com has some fascinating photos of the spillway during construction in the 1950s.
Thanks to Mark and fogonazos.
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awesome find!
I’m guessing site traffic might increase at the mention of ‘Glory Hole’ !
Here is a pair in the UK.
Placemark: Google Maps / Google Earth
Good link Gesh – those are bellmouth overflows in Ladybower Reservoir, Derbyshire, England, which are known locally as “The Plugholes”.
Well, you need quite a big plug for that drain!
(The above comment is only to increase site traffic even further)
Enough bad jokes… The upstream lake is much bigger than it appears to be close to the dam, and they have weird bridges: Placemark: Google Maps / Google Earth
I think Escher designed that bridge.
There is another ‘Glory Hole’ on the Oregon, Idaho border. Pretty much the same as Baryessa. but, I think it is slightly smaller, but not much.
Placemark: Google Maps / Google Earth
really Awesome O.o
we haven’t got anything like this in italy…
only big and void dam and dement politics…
and no one tried to go inside this hole..?
@Michi – the road to the south is fenced off and in the google map you can see the buoys strung across the lake to the west – which are obviously designed to keep people away.
I don’t know of anyone trying to go through one, but I did read somewhere that people have occasionally used them to commit suicide. However I’m not sure if that’s true or not.
If the first several hundred feet weren’t straight down I’d say it looks like it’d make a good water slide tube. All you’d need would be a good amount of extra rainfall and a inner tube!
If you wanted to kill yourself in one of these, the one at Llyn Celyn reservoir in Wales might be a good choice, since there’s a walkway right over it.
Placemark: Google Maps / Google Earth
I lived nearby when I was in college and I was told that people have committed suicide in it. They do keep the area near the dam and the hole roped off to prevent anyone from accidentally going in. This lake was also the site of one of the Zodiac killings.