If you have been following it as i have, you would know the spillway was temporarily finished and usable in Nov, 2017 if need be. This video back from Nov 2017 well explains what's going on, and should answer all your questions. https://youtu.be/pW0y_wkrCwM. If you watch the DWR or blancolirio videos on the spillway you will see it was all planned out and executed amazingly well.

blancolirio: Orville spillway videos https://www.youtube.com/playlist?list=PL6SYmp3qb3uMCqXIp7mYmiAPeEVoazpUE

DWR Orville videos https://www.youtube.com/playlist?list=PLeod6x87Tu6eVFnSyEtQeOVbxvSWywPlx

So what if they need to use either spillway before they finish this project? It looks like even the main spillway is a long ways from being complete. While the emergency spillway can probably hold off except for another emergency of course...

I'd imagine if I lived downstream I'd be thinking, a little too late on these repairs, given they were requested a decade ago.

The Orville spillway decision making sounded like a plot for a disaster movie with a happy ending. Interesting and scary stuff. Thought it might interest you and @oritteropo
https://youtu.be/nCgrXPB6Zeg

Almost all of that pile below the spillway is rock eroded from the hill, not concrete. I think one of the videos said 1 million cubic feet or so of material?

Here's a few still shots of the bottom of the spillway being dredged to open the channel for the power plant to start discharging water. Note, one thing not seen in all those piles of concrete that have plugged the channel.....rebar. Not one piece seen in any of these shots of millions of pieces of concrete.

Your video, Oroville Spillway Damage, Rebar?, Oroville Dam 2-27-17, has made it into the Top 15 New Videos listing. Congratulations on your achievement. For your contribution you have been awarded 1 Power Point.

What I keep reading is the lake is actually a maximum of 900 ft deep, and the lake is currently about 835 ft deep after weeks of high volume draining.

Here's a current view of the spillway damage....
*related=https://videosift.com/video/Oroville-Spillway-Damage-Rebar-Oroville-Dam-2-27-17

Lake Oroville dam spillway damage has been added as a related post - related requested by newtboy on that post.

Oroville Spillway Damage, Rebar?, Oroville Dam 2-27-17 has been added as a related post - related requested by newtboy.

Congratulations! Your video, Lake Berryessa is 3.5' OVER the Glory Hole Spillway, has reached the #1 spot in the current Top 15 New Videos listing. This is a very difficult thing to accomplish but you managed to pull it off. For your contribution you have been awarded 2 Power Points.

This achievement has earned you your "Golden One" Level 4 Badge!

Your video, Lake Berryessa is 3.5' OVER the Glory Hole Spillway, has made it into the Top 15 New Videos listing. Congratulations on your achievement. For your contribution you have been awarded 1 Power Point.

For reference: flows at the their highest out of the spillways were exceeding the flows at Niagra Falls---

And---in 2005, 3 environmental groups tried to get the State to concrete armor the emergency spillway---they protested it would be too expensive and not necessary...And of course, with the main spillway out of action, the emergency spillway has started to erode as well---and 200,000 people have been evacuated. To my understanding---and I'm not a hydraulic engineer---the risk with the emergency spillway is that the water flowing over the concrete "cap" or "curb" has started to...duh...erode the earth below the cap. If it erodes too far, the concrete cap will tumble off, a 30 foot wall of water will cascade over the edge, the the dam will start to erode...

#OrovilleSpillway for current tweets


Orville is under mandatory evacuation as they fear the emergency spillway may fail.
http://www.ktvu.com/weather/weather-news-headlines/235380255-story

Why the spillway may fail from California Dept. of water resources. https://www.periscope.tv/w/1yoKMeddkVeKQ

video
http://www.kcra.com/article/evacuation-orders-issued-for-low-levels-of-oroville/8735215

http://www.nbcnews.com/video/evacuations-underway-as-oroville-dam-prepares-for-failure-875775043662

Your video, Lake Oroville dam spillway damage, has made it into the Top 15 New Videos listing. Congratulations on your achievement. For your contribution you have been awarded 1 Power Point.

More recent videos of emergency spillway
https://youtu.be/bephol1Ormg

(edit and updated w/ better video)
and now flow from emergency spillway at the river https://youtu.be/Gchf6COGAKQ