At what point would you see all that water coming down the hill days ago and say, "sure seems safe to stay here?" Do you not have any common sense? These people should have either, A, left days ago, or B, Built an ark to enjoy the ride.

 

...or C, eliminate the threat. :lol2:

 

 

They dodged the perverbial bullet last night. They did that by increasing the main spillway flow to take the lake down below the 901 level. 901 is the key level where the flow starts to go over the emergency spillway area and, now, an unplanned area to the the side of the emergency spillway. This has to be a new and serious concern.

 

The emergency spillway - and the new unplanned overrun area - are not 'controlled' at all. If the water gets to 901 ft level the water will spill over these areas. When below 901 - it won't.

 

They are worried about the potential of undercutting the emergency spillway as noted by BigVman above. if the spillway - which acts a a small dam - collapses due to undercutting then a major disaster happens. Again - the area to the left where water is going over the parking lot and exiting outside either spillway has to be a serious concern since nothing was engineered to deal with this situation.

 

Every inch of lake level that is above 901 is a risk situation and more rain is expected this week. Its still a critical situation.

I feel like the spillway should have been fully open since the very thought that this could happen.

 

Also, if you build your house below a dam, this is the kind of thing that you knew could happen. It's always very unlikely but you have to know it's possible

Hopefully they are draining as much as possible off of it to prepare for the added rains.

 

Here is an old photo of the same area.

 

Luckily the area just behind the Emergency Spillway looks to be very shallow as compared to the rest of the lake.

...or C, eliminate the threat. :lol2:

 

Wheres Frozone when you need him to turn this all to ice and stop the water.

Now wait just a doggon minute...you mean they didn't have the main spillway opened completely to begin with?!? :ohbrother:

 

I have suddenly had the urge to not care what happens with this now.

A hole developed in the concrete in the main spillway and that caused some problems on its own before the water peaked. if you look towards the bottom of the concrete spillway I believe you will see damage done there because they had to open the water flow fully in that area and that is what they were concerned about

A hole developed in the concrete in the main spillway and that caused some problems on its own before the water peaked. if you look towards the bottom of the concrete spillway I believe you will see damage done there because they had to open the water flow fully in that area and that is what they were concerned about

 

I guess they assumed putting a ton of water on an area that had not see water in this millennium everything was just going to work perfectly.

I feel like the spillway should have been fully open since the very thought that this could happen.

 

Also, if you build your house below a dam, this is the kind of thing that you knew could happen. It's always very unlikely but you have to know it's possible

 

My people got up out the valley after '37...but then again, we were just redneck country folk, not sophisticated Cali types....

Now wait just a doggon minute...you mean they didn't have the main spillway opened completely to begin with?!? :ohbrother:

 

I have suddenly had the urge to not care what happens with this now.

 

 

 

A hole developed in the concrete in the main spillway and that caused some problems on its own before the water peaked. if you look towards the bottom of the concrete spillway I believe you will see damage done there because they had to open the water flow fully in that area and that is what they were concerned about

 

Here is the problem on the main spillway. The damage is working its way UP the spillway when they run this. These pictures are a few days old. After running the main spillway hard overnight the damage is probably much worse today. Obviously, even from just these pictures a rebuild of the lower part of the massive structure will be needed when this is done.

 

Link to picture that show how much they 'lost' of the main spilway last night.

 

Use the power-line towers to compare the two pictures.

 

Imgur: The most awesome images on the Internet

Are they sure the structure of the dam itself is solid?

Flowing over the emergency spillway now - the one that has never been 'used' before. There is no control of its use to even test it. It the last failsafe to protect the dam structure. Unfortunately, the water is going underground right at the concrete wall.

 

Twitter with some video:

 

King Zombie (@TotalZombie) on Twitter

 

A view from a professional in Ohio on the situation on Linkedin:

 

https://www.linkedin.com/pulse/oroville-dam-failure-scott-cahill

 

The guy in the linkedin link above has a podcast out from yesterday.

 

Its 43 minutes long. I have not listened to all of it but skipped through some parts.

 

Are they sure the structure of the dam itself is solid?

 

The 'dam itself' has not shown signs of issues.

 

That stated. As the video above points out - the water level in the lake has never been as high as was this weekend - ever. So this is uncharted territory somewhat.

 

Those levels will likely return this weekend or earlier with rains and snow coming in. And the Emergency Spillway will 'actuate' again like it did last weekend. No human controls the flow once the level is above 901'. They are trying to lower the lake now but it likely will not be enough to keep the level from reaching 901 again.

 

The area from Oroville down to Sacramento is at risk at this point. Not so much from the main dam risk but because there will be a disaster if the ES gets undercut and 'fails' (i.e. gets pushed over by the water pressure. That will release a large amount of water even without the main structure having an issue.