What is your source for this? The emergency spillway for that dam is a few hundred yards to the northwest of the dam, over solid earth. Water over the spillway cannot cause the dam to fail.
correct but the emergency spillway is very high built ABOVE the bedrock
Have you seen pictures of the emergency spillway failure? It is an earthen damn. It is catastrophic. that thing blows the whole thing blows. Green or lantern, you dont have a bit of engineering corp in you. This is catastrophic.
At the high point the emergency spillway is adjacent to the dam.
That "solid earth" is being washed away
see this :
https://www.youtube.com/watch?v=Nq_CJNoIdvo
The emergency spillway for that dam is a few hundred yards to the northwest of the dam, over solid earth. Water over the spillway cannot cause the dam to fail.
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The dam is not failing. The emergency spillway is failing. It says that pretty clear in the title.
I think the Grand Canyon was solid earth at one time, rock infact.
The emergency spillway is eroding badly.
Whitewater — OK
Muddy water — BAD. VERY bad.
The dam proper is not in jeopardy, but there is a whole lot of muddy water boiling up below the emergency spillway, which means that there’s active hydraulic excavation going on below the face of the emergency spillway.
That is a HUGE problem because the Emergency spillway is nearly as high as the main portion of the dam, itself. So, if the Emergency Spillway gets breached, it won’t matter that the main part of the dam is still standing firm.
Worse, though, a breach below the face of the Emergency Spillway would permit lateral erosion at an alarming rate that COULD traverse sideways from the Emergency Spillway, to the Main Spillway, which would undercut and topple the topworks of that structure. From there, nothing could stop that lateral erosion from continuing on to the main portion of the dam.
This is a very serious situation.
From what I gather, the concrete spillway has degraded and there are now large cavitation holes in the concrete which have exposed the earth fill base to serious erosion.
When reporters try to ‘splain anything involving engineering or science, it is difficult to figure out what is really happening; but, apparently the penetration of the spillway concrete is why they are dumping super bags of large boulders into the spillway from helicopters.