Oroville Dam Spillway Failure

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Paveway IV

New Member
This area is an at risk/high risk section that needs to be addressed IMO.

The parking lot spillway is a minimal, narrow, concrete wall. I suspect it isn't very deep at all.

This is from the 2005 FERC .pdf - I believe the ogee face on this 'Parking Lot Weir' section is upstream, as the downstream side appears quite square in the various photos. I cut and pasted this from the .pdf, so the text/symbols inside the profile are unreadable. This weir appears to be about 4' across and maybe 3' high if the proportions are correct in Fig. 7.

parking_lot.png

I believe the admin, Mick West, asked about the height. The figure indicates that weir is the same crest height as the much larger ogee crest weir: 901'.

Parking_lot_weir_shadow.png

Judging from the shadow length/angle, I would have to say the downstream face has been scoured/eroded to nearly the full 3' depth of the weir. This wasn't problematic with a little over a foot overtopping, but can not be good in the long run for higher levels of overtopping or hours/days of flow IF the emergency spillway 901' crest is exceeded again.

There's no reason to think the rock in front of the Parking Lot Weir is not just as fractured and equally subject to erosion as the rock in front of the main weir. It was likely ripped to grade and filled with dirt. It looks nice and flat now because the dirt has not yet washed out.

Which brings up an even bigger issue that may come up in the future (aside from all the existing erosion issues in front of the main weir): the topology shows somewhat of a downslope channel from the far corner of the parking lot.

parking_lot_topo.png

This would be to the left of the red marked channel draining from the main weir. That corner of the parking lot was where they were dropping in bags of rocks. If the road at that bend had given way, there might have been a pretty rapid head-end erosion up to and beyond the parking lot weir. Failure of the parking lot weir wouldn't have been catastrophic, but any uncontrolled erosion below the 901' level is a serious problem. Would it have cut a meandering 2' channel downslope to/past the road, or a 20' one? Would that have taken an hour or forty hours?

I'm not suggesting this is 'the biggest' problem the engineers have to worry about right now by a long shot, but it's another one they really don't need right now in addition to all the other failure points and erosion scars they're patching up.
 

EricL

Member
Ever since I first saw a close up picture of the emergency spillway, I have been trying to understand what was going on there. Even before the water started going over it, there was nothing there to absorb the force of the water and stop erosion of material up close to the weir. After following this site for a couple of days, I MAY have an answer thanks to all the things that have been posted here.

When they were building the dam they knew they needed a weir to act as the emergency spillway, they knew that the top of it needed to be at 901, and they knew they needed it to the left (looking upstream) of the main spillway. They needed to put it on competent (solid) rock, and they needed a shelf of competent rock out in front of it, say 100 feet wide to stop the upstream erosion. You can see this in the drawing on reply #354. Those little hash marks at the bottom of the cross-section of the weir are a standard symbol for rock.

So they started removing the soil and loose rock to the left of the main spillway until they had a bench 150 feet wide. They removed the rock with rippers (post #428) because with a ripper you can create a level surface, and you know when all the loose or weathered rock has been removed. As they moved further away from the main spillway the competent rock was higher, so the rock bench kept moving up. This is why the weir gets shorter as it moves to the left.

The reason the competent rock gets higher is because there was more soil over the rock, as can be seen in post #450. The Rock Whisperer in post #409 explains that the rock in the area breaks down due to its exposure to rain an air, so the competent rock is generally at some constant depth under the surface of the soil. As the hill get higher, the solid rock is located at a higher elevation.

As Mr. Neubauer states in post #374 the designed weir on solid rock will not go anywhere.

The light bulb really went on for me when I saw the second picture in Post #484. You can see what looks like a solid rock wall that is perfectly flat on top of it. It appears to be a solid block of rock. On top of this big slab of rock is a very small wall, the top of which is a 901 feet. This wall is also shown in the cross-sections on Post #354. So in this area they found competent rock at an elevation slightly lower than 901 an needed this very low wall to keep the top of the emergency spillway consistant. Past this area (the parking lot) the hill goes on up (as can be seen in the backgound of the second picture in Post #484) so they didn't need to extend the emergency spillway any further.

So at the end of construction they had an emergency spillway extending from the main spillway all the way to the hillside, AND there was a shelf of strong competent (solid) rock extending out in front of it for 100 feet (or so.)

The problem is that as the Rock Whisperer pointed out, this rock can weather greatly when exposed to the elements. So over the next 60 years the rock broke down and when the emergency spillway was used for the first time a couple of days ago, the "solid" rock started to erode. It was "solid" 60 years ago when they built the dam and everybody thought it was still good up until a couple of days ago. I sure they were quite surprised when their "solid" rock started to wash away.

I would expect that the work they are doing now is just a patch. When the danger of flooding is over I would expect that they will build a substantial structure in front of the entire length of the emergency spillway to make up for the missing "solid" rock.
Brad, I haven't tried to look for all the details in all the photos you mention, but I do think your idea regarding the layout of the concrete structure of the emergency spillway makes good sense. It seems like a good way to explain what seems to be an ever-decreasing height of the overflow structure from right to left (using your definition of right and left), and it also would seem to answer the question regarding the apparent inconsistency in design, when comparing the weir to that very small wall to the left. It would also likely explain why the designers thought it was okay to just end the weir so abruptly, apparently not being concerned about erosion at that end point.

Also, while rock weathering is generally an extremely slow process, in my part of the country at least, I have seen the walls of certain rock cuts have pockets which degrade and collapse in the time since they were first exposed 30 to 40 years ago. However, such degradation probably would have been expected by knowledgeable person who examined these spots closely at the time of excavation, and so regarding the topic at hand, I'd bet that for the most part, rock which is soft now was also soft when first exposed at this site, but just not accurately evaluated in terms of its durability. I can't recall who posted this, but someone already pointed out that the eroded hole below the far left end of the weir is at the same location where an aerial photo during construction revealed a pocket of much darker rock - probably material that was more weathered that that of the immediate surroundings (the same color trend can be seen at the top of any exposed rock face where erosion has occurred, and that supports that poster's idea).
 

aczlan

Member
Um... guys... the spillway used two different kinds of concrete.

https://archive.org/details/zh9californiastatew2003calirich
Page 93
Interesting document. I also ran across some interesting thinga about the construction of the dam/spillway/emergency spillway:
If you download the b&w PDF ( https://ia800302.us.archive.org/3/i...lirich/zh9californiastatew2003calirich_bw.pdf ), Page 100 says:
Page100 of https://ia800302.us.archive.org/3/items/zh9californiastatew2003calirich/zh9californiastatew2003calirich_bw.pdf said:
The flood control outlet radial gates are operated by
electric-motor-powered cable-drum hoists located on
the hoist deck. The gates may be operated locally or
remotely from the Oroville Area Control Center.
Normal power for hoist operation is supplied through
a buried distribution line from Edward Hyatt station
service power system. Standby power is available locally
in the form of a 55-kW generator operated by a
liquid-propane-gas-fueled engine. Normal power supply
is sufficient to operate all gates simultaneously.

Later on the page it says:
Page100 of https://ia800302.us.archive.org/3/items/zh9californiastatew2003calirich/zh9californiastatew2003calirich_bw.pdf said:
Emergency Spillway. The grout curtain was continued
under the left reach of the emergency weir
near the upstream face, and formed drains are used
under the downstream half. The crest of the emergency
weir to the right, which is only 1 foot above the
excavated channel, is keyed 2 feet into the foundation.
Both weir sections were checked for overturning and
shear friction safety factor and found to be satisfactory.

If you want to read about how the dam was built and the nitty gritty of the technical details of the design considerations, start at page 63 of the aforementioned PDF.

Aaron Z
 
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Christopher B.

New Member
A few thoughts mostly on the main spillway (concrete trough).

It appears that the original failure was just beyond (below) the change in slope and a guess would be that it was resting on fill there, the fill became saturated from water leaking through the floor, eroded away and dropped a panel allowing water to exit under the wall, and the flow quickly destroyed the remaining floor that was on fill and enlarged the new exit point. Continued migration uphill would likely be slow but steady for regions of the floor resting on fill - although the change in slope as it moves upward will decrease the energy available for such work. Probably as the trough approaches the gates it is increasingly tied to bedrock - I would guess this is why it is believed that it can sustain continued releases for months without catastrophic failure. Most probably the lower portion will continue to be destroyed but this poses no threat to the dam or the upper portion of the spillway.

You can see the bedrock below the failure clearly in the photo posted by the WP with the varied colors indicating degree of weathering.



That the side wall itself has not failed but bridged the substantial gap gives some indication of what the weir structure could withstand - even if undermined. Weak point of the weir structure is the end interface with rock at parking lot and perhaps the other end as well, but some kind of catastrophic failure seems unlikely. Depends on the strength of the bedrock at the ends and beneath.

Bedrock in general looks highly fractured and heterogeneous. Hard to make generalizations about how it will behave - but because of the vertical orientation of the fractures it can only erode in chunks, not in sheets - deep narrow canyons could develop in weak zones but erosion would be heterogeneous, like the substrate. As for the D9s with rippers - they never could have been used in solid, unfractured bedrock - that would have required drill and blast.
 
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aczlan

Member
I'm puzzled. Your quotes aren't relevant to the type of concrete in the spillway.
Sorry, I never got back to adding a explication to the beginning of my post, those were just some other interesting things I saw in that document that are related to some of the myths that people have been spreading about the spillways (such as that the emergency spillway is built on dirt rather than being set in rock and that if they lose the power lines across the emergency spillway they will lose power to control the gates)
I updated my post to reflect that.

Aaron Z
 

john r

New Member
Here is a KCRA raw heli footage from tuesday afternoon, but its dark and jumpy.

removing this bad re-broadcast youtube link].

KCRA now has this on thier facebook page
 
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Continued migration uphill would likely be slow but steady for regions of the floor resting on fill - although the change in slope as it moves upward will decrease the energy available for such work. Probably as the trough approaches the gates it is increasingly tied to bedrock

Actually, each section is anchored to bedrock and is resting on 5-6 feet of fill. So fill probably drops out at the fracture point, and the anchors into rock continue to provide support. Don't know if the anchors can support the slabs without the fill.

(page 96 of recently linked document has an illustration of the chute which seems to mention fill)

The reinforced invert slab has
a minimum thickness of IS inches and is anchored to
the rock with grouted anchor bars and provided with
a system of underdrains.
 
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EricL

Member
Okay, this is a followup post to my earlier remarks on under-slab drainage, and these photos from one of Mick's earlier posts illustrate what I'm thinking about this time around.

This time, the question is, where is all that water coming from, as seen on the sidewalls of the spillway? I'm guessing that those drain outlets on the walls are 9 or 10 feet above the slab, so there's a significant amount of flooding of the backfill behind those walls. That water must be moving downhill, and naturally there's no drainage from the right wall downhill from the failure point, since all the water that was there would have escaped from the wall backfill once it reached that location. Maybe this is runoff from the surrounding terrain during a time of heavy rain. Maybe it's water that leaked around the control structure at the top of the hill. Maybe it's water that leaked through the slab at numerous locations during a time when the spillway was full, so that it then "piled up" to the height of the wall drains at locations farther down the hill, and in that case, these photos would have to have been taken not too long after flow through the spillway was shut off.

In my related post I described the high risk of undermining the structure if any of the grading fill was somewhat, or very, open-graded (from gradation standpoint, that's described as "poorly graded", and was the term I used in that post). Here, we see possible evidence of a different problem - water pressure. If the water is "piled up" as high as those wall drains, and let's assume that's a height of 10 feet above the slab, then the pressure of the water beneath adjacent parts of the slab is that same 10 feet plus the thickness of the slab. Now, when the spillway is full, this won't matter because of the weight of the water being carried, but when empty as shown in these photos, the net upward force is considerable. If this is more than just isolated pockets of soil flooding, and it sure looks like it must be, it could potentially cause the slab to fail, or even buoy up entire affected portions of the spillway (and in the one picture, the affected portion is basically the entire length of the thing). Even a slight, temporary buoying of the structure would likely allow rearrangement of the supporting soils by the downhill flow of water, thus later leading to failure. The general working rule of thumb is that a head pressure of 3 feet will lift a slab that's one foot thick, but based strictly on densities, it would take less head pressure than that. Here, the head pressure appears that it must be a lot greater than that. This is a genuine problem. I've heard of swimming pools breaking free of their surrounding patio structures and floating right up out of the ground if they were drained without first dewatering the surrounding soils.

So as before, what my pondering is about, is maybe this extreme flooding of the surrounding soil contributed to the original failure. Obvious questions to ask are, how does the under-slab drainage system work? I just heard a second-hand account that there might be drains exiting the floor area laterally at intervals along the whole length, and we already have seen that there are a few drains exiting from beneath the slab at the downhill end, as I described earlier. It seems as though those downhill drains must provide enough back pressure to allow the overall soil flooding at some times, as illustrated in these shots, and when water is present that high up the walls on the outside, and since surely there's effective continuity between under-floor water and behind-the-walls water, lateral drains really aren't solving the problem at such times (they would help a lot when flooding the soils is less severe).

By my reasoning, those wall drains ought much less high. Sure, they'd let water from the chute escape to the surrounding soils, but with the right backfill, would drain back just as quickly as the water level within the chute were reduced (there's have to be a safety rule that the flow be shut off somewhat gradually, never abruptly).

That spillway failure happened for a reason, or combination of reasons, and maybe this is part of that. I could be wrong but the possibility makes sense to me.
 
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Pterosoar

New Member
The Sacramento Bee spoke with Joe Countryman, a member of the Central Valley Flood Protection Board and a former engineer with the U.S. Army Corps of Engineers for context on the engineering issues in the Oroville Dam crisis...
The Bee: If the top of the emergency spillway goes, is that basically dam failure?
Countryman: It’s not going to be the (main) embankment failure, but it’s a failure. If it does happen, there’s nothing saying that the ground is going to stay where it is. That force of water will start tearing that hill apart, and it could eat back into the reservoir and drain the reservoir.
http://www.sacbee.com/news/local/article132356269.html
-----------
I'm not a geologist but my understanding of the underlying bedrock is that it is Jurassic greenschist which is highly fractured and can be quickly eaten away by forceful hydraulic action. This, I believe, is what Joe Countryman is referring to.

I was stunned to hear that the population is being let back in to Oroville on the eve of a major rain event. This Ventusky data comes from NOAA. I can see no way the dam, with a saturated catchment of 3,600 square miles, will survive this.
https://www.ventusky.com/?p=39.58;-120.37;6&l=rain-ac&t=20170223/03

If the main spillway erodes and collapses to the gates, they will have to shut it down or loose the main embankment. This will send the entire outflow over the emergency spillway. [unsourced fearmongering speculation removed]

Also, trying to fix the emergency spillway erosion with helicopters instead of dump trucks is one of the most laughable things I have ever seen. The level of incompetence is breathtaking!
 
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Okay, this is a followup post to my earlier remarks on under-slab drainage, and these photos from one of Mick's earlier posts illustrate what I'm thinking about this time around.

I just edited my post above yours with a mention of underslab drainage. Don't know where it drains to, but maybe that's the source of the water streaming in from the sidewalls in some pictures. Maybe the underslab drains feed into an outlet on a lower level of the chute.
 

Christopher B.

New Member
Actually, each section is anchored to bedrock and is resting on 5-6 feet of fill. So fill probably drops out at the fracture point, and the anchors into rock continue to provide support. Don't know if the anchors can support the slabs without the fill.

(page 96 of recently linked document has an illustration of the chute which seems to mention fill)



If you look at the WP photo you can see that complete floor panels fell/were carried away over deep fill while chunks and pieces were broken away over the bedrock (where the anchoring, whatever it is, was effective). Perhaps the initial failure was caused by hydraulic pressure from saturated soil as was suggested above by EricL. The soil above the failure should be able to drain more effectively now though :)

(Edited to add photo link as per moderator's request)
 

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deirdre

Senior Member.
Moderator Note - deirdre
Metabunk is not a general discussion forum. Please don't make statements as if they are fact without linking supporting evidence.

Do not make members search back through thread to 'look at a photo'. Include the actual photo you are referring to in each post. Mark the photo with arrows etc if needed to show exactly what you are looking at.

External quotes should be in external quotes. use the 'x' icon on your comment box.

https://www.metabunk.org/posting-guidelines.t2064/

https://www.metabunk.org/metabunks-no-click-policy.t5158/
 
If you look at the WP photo you can see that complete floor panels fell/were carried away over deep fill while chunks and pieces were broken away over the bedrock (where the anchoring, whatever it is, was effective). Perhaps the initial failure was caused by hydraulic pressure from saturated soil as was suggested above by EricL. The soil above the failure should be able to drain more effectively now though :)

Perhaps. Now that I've seen the photo, I see that there are no visible drainage pipes on the side closest to the camera, so we can't tell where the sidewall water is coming from. I'm not seeing anything in drawings of the chute either, only a fuzzy note which might specify installation of those drain holes in the side walls.

As for the anchors, it seems to say to use #11 anchors. Is that a standard piece of construction hardware, or more likely to mean use #11 rebar?
 
Here, we see possible evidence of a different problem - water pressure. If the water is "piled up" as high as those wall drains, and let's assume that's a height of 10 feet above the slab, then the pressure of the water beneath adjacent parts of the slab is that same 10 feet plus the thickness of the slab.

There is one bit of evidence in your photos. Look on the left photo, at the right sidewall just below the bottom of the break. Is that a drain which is spitting a lot more water into the chute than the other drains? That supports the theory that those are drains from the immediate area, rather than some silly place like 200 feet further uphill.

 

jwchesnut

New Member
Do historic spillway events have the same level of drainage off the underdrains and through the sideway discharge.
The flow through these drain (above the damaged region) may indicate the bedding under the drain is compromised, and failure at another locus is possible higher up the discharge chute.
Note in the paired image posted immediately upthread that the drains have stopped flowing below the break in the later image. In that flow event, the water sheeted sidehill. This indicates to me the underdrains are collecting water seeping through the expansion joints, and drain out quickly rather than a relic of saturated rain-soaked soil. Excess flow in the upper segment drains could be associated with undermining of the concrete bed.
 
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Christopher B.

New Member
There is one bit of evidence in your photos. Look on the left photo, at the right sidewall just below the bottom of the break. Is that a drain which is spitting a lot more water into the chute than the other drains? That supports the theory that those are drains from the immediate area, rather than some silly place like 200 feet further uphill.


I believe it is a chunk of concrete - left photo, LR of damaged area. Left photo: drains on left all delivering water to spillway, embankment intact. Right side only drains above damaged area delivering water, below embankment eroded away.

Right photo only drains above failure delivering water, both sides - so water path has been severed to lower portion, left side, with intact embankment. Also, an additional row of floor panels has disappeared on the uphill side of the failed section along with portions of both side walls. Reddish/yellowish fill or weathered bedrock is visible beneath the uphill section. Damage to side wall LR terminus of spillway.
 

Kalinahin

New Member
Hey
Would this section from the excellent book linked previously possibly insinuate that the Emergency Spillway weir profile is not uniform, but follows the terrain?

Oroville Dam Emergency Spillway Section.jpg

I'm from Denmark and have nothing to do with dams... yet I find myself fascinated by this discussion - gj guys!
 

john r

New Member
Let's drop the rose-colored glasses for a moment.




Look at this CDEC dam data right now:
http://cdec.water.ca.gov/cgi-progs/queryF?s=ORO
They're running at 99,000 cu ft/s outflow. They've been doing this all day. They're telling the public they're lowering the reservoir level by 50 feet. But the level, right now, is only 4 feet from the lip of the emergency spillway and it has been climbing all day! Something isn't right with all this rosy logic.

Slow down, the current water level is 883 ft, which is 17 feet from the lip (901ft.) They are reducing the level at least 1 foot every 3 hours right now.

(PST) FEET
02/14/2017 21:00 883.60


At the Noon meeting, I beleive they said the projected the highest inflow of the upcoming rain to be less then 100,000 CFS.
 
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skicopper

New Member
[Mod: misleading post removed]

Mick posted this yesterday. Chart shows that inflow rarely gets above 100,000 cfs. I know little about hydrology but it appears they are releasing enough to keep the pool elevation on a downward trend. Whether or not the spillway can handle that amount of outflow for an extended period of time is a totally different story, but it seems to be working fine for now.
A94C9745-EF8C-4A3D-AC4E-CF4B7DC2B433-7153-000006B1EE8F2451_tmp.jpg
 
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s5150

New Member
Inverted (to avoid takedown, apparently) Satelllite video feed apparently from KCRA helicopter today. At 18 minutes: Source: https://www.youtube.com/watch?v=ahOEdiYj8z8#t=18m0s


shows bulldozers building trenches to river upstream from main spillway back towards dam. It would seem to be a stretch that they're trying to dam backflow from that point.

There are dropouts in the video, but watch the zoom out shot at 20 minutes. If the main spillway fails farther back, there is a valley in the mountain parallel to the damn. Where would that water go, and are they prepping for it?
 

Mick West

Administrator
Staff member
Inverted (to avoid takedown, apparently) Satelllite video feed apparently from KCRA helicopter today. At 18 minutes: Source: https://www.youtube.com/watch?v=ahOEdiYj8z8#t=18m0s


shows bulldozers building trenches to river upstream from main spillway back towards dam. It would seem to be a stretch that they're trying to dam backflow from that point.

There are dropouts in the video, but watch the zoom out shot at 20 minutes. If the main spillway fails farther back, there is a valley in the mountain parallel to the damn. Where would that water go, and are they prepping for it?

Interesting video, here's those bulldozers in context (flipped correctly)
20170214-233054-p4g7z.jpg

Seems like it would take a long time to dam the backflow there. However they have several days. And they can always undam.

If they are damming the backflow in the pond then that must be in case of a quite large release of water. But is there some other explanation for these dozers?
 

Mick West

Administrator
Staff member
To some of the earlier comments about the quantity of equipment in play and the methods being used to deploy materials - most of this video is worth watching as it spends a generous amount of time on different areas of the works in progress.

For example:
20170214-234107-16j9k.jpg
Seems like a steady stream of cement and rock trucks.

Excavators on towable platforms?
20170214-234701-wg4dp.jpg

There's also a wide shot confirming the main spillway damage has not moved.
20170214-234320-j1knj.jpg
 
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CeruleanBlu

Senior Member.
as to your question @Mick West, the dozers there possibly attempting the backflow damming, looking on Google Earth at the outlet pipe across the river, it would make sense to attempt to make the block there to keep water from getting back to this discharging pipe visible here.

 
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Ethan O'Connor

New Member
Relevant to the quality of the rock uderlying the lined spillway, from the "California State Water Project" text:

Various types of spillways were studied and mod-
eled to arrive at the final structure. The original de-
sign consisted of a control structure with radial gates
to pass the total spillway design flood. A short con-
crete apron was to extend downstream from the con-
trol structure, and then the flows were to be turned
loose down the hillside in an excavated pilot channel
.
As the spillway would operate on the average of every
other year, this plan was determined to be unaccepta-
ble based on the large quantities of debris that would
be washed into the Feather River and could ultimate-
ly affect power operations
.

...
[However]
No concrete lining is used in the plunge pool [at the base of the lined spillway]
as rock of adequate quality exists near the ground
surface.

Note that there's no comment on structural risk due to erosion.

Elsewhere in the text, it's noted that both abutting ridges have steeply dipping shear patterns that strike perpendicular to the dam. Weathering in the sheared zones extends at least 100' into the bedrock and these zones would be substantially more susceptible to erosion.

Finally, it struck me that the text spends many pages discussing the design of the lined section of the spillway, but only devotes a single paragraph on the emergency spillway:

Emergency Spillway. The grout curtain was con-
tinued under the left [viewed from the upstream side]
reach of the emergency weir near the upstream face,
and formed drains are used under the downstream half.
The crest of the emergency weir to the right, which is
only 1 foot above the excavated channel, is keyed 2 feet
into the foundation. Both weir sections were checked for
overturning and shear friction safety factor and found
to be satisfactory.

http://www.archive.org/stream/zh9ca...rich/zh9californiastatew2003calirich_djvu.txt
 
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BrokenLug

New Member
Woo Hoo, 2 backhoes, 3 cement trucks and 1 cement pumper.

I'm pretty sure the 180,000 people evacuated down below the aux-spillway are safely reassured that this is enough.
 
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Marc Kupper

New Member
Using the daily elevation data available from CDEC[1] I have created a spreadsheet that shows the average elevation from 1985 through 2016, the maximum for each date of the year from 1985-2016, and the data for 2017 tossed on top of that. It helped me understand why they are trying to draw the reservoir down to 850 feet. Here's the chart on Google Sheets and below is the resulting chart.[2]





[1] http://cdec.water.ca.gov/cgi-progs/...date=01/01/1900+00:00&end_date=now&download=y

[2] The chart image is from the same sheet in Microsoft Excel. I don't know how to edit some of the chart details in Google sheets. I've enabled editing of the sheet by everyone and so if someone's a Google sheet's wizard it would be great if. 1) Make the format of the Summary/Dates column mmm-dd and the format of the horizontal axis mmm. I can't figure out how to make the formats different. 2) Google defaulted to just four vertical grid lines in the summary chart. I want one per month.
 

jonnyH

Senior Member.
Woo Hoo, 2 backhoes, 3 cement trucks and 1 cement pumper.

I'm pretty sure the 180,000 people evacuated down below the aux-spillway are safely reassured that this is enough.
Are you suggesting they should use more equipment than is necessary in order to reassure people?

Is it not just possible that the resources that have been put to work are enough to complete the repairs within the anticipated window of time?
 

Graham2001

Active Member
For an idea of what the Conspiracy Theorists are up to, first up a video on one of Alex Jone's channels


This comes from a channel called Lisa Haven and the description beneath it has lots of links where you can buy gold, doomsday supplies, etc and of course to Alex Jones.


What both are pushing is the line that the government of California 'wasted' money on supporting refugees, illegal immigrants. Black Lives Matter, etc, etc that could have been used to fix infrastructure and that if you support Trump then everything will be fixed, but in the meantime buy what I am selling...
 

RedNeckGeek

New Member
With respect to equipment, I had occasion to visit the closure barriers on Highway 70 where it enters the Feather River canyon just east of Jarbo Gap, CA late on the afternoon of 2/13/2017. The CalTrans flagger there told me that the road wouldn't be open anytime soon. The pavement had been undercut in several places to the east when the highway was flooded and they were having trouble holding on to equipment because of needs at Oroville Dam. If CalTrans is having to scavenge equipment from other high priority activities to meet needs at the dam, it doesn't seem likely to me that they're doing it as a dog-and-pony show for the public.
 
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aczlan

Member
Woo Hoo, 2 backhoes, 3 cement trucks and 1 cement pumper.
I'm pretty sure the 180,000 people evacuated down below the aux-spillway are safely reassured that this is enough.
If you look at the mirrored video at 14:41 (screenshot below), they have two more pumper trucks sitting where the spillway joins the emergency spillway (not sure what they have planned, but they are available if they need them), at that point, there are at least 4 trucks on site (2 unloading into the active pumper, one coming in and one going out). This screenshot also shows another reason they probably dont have more trucks coming in. Those off road dumptrucks take up most of a "2 lane" road, so they can only run so many at a time as one truck (either in our out) needs to pull off to the side to let the trucks going the other way pass:
Orovillebottleneck.PNG

The trucks appear to be coming from Mathews Ready Mix (based on their paint scheme) which Google Maps says is ~20 minutes away from the dam's address. Figure 10 minutes to make it from the dam's address to the unloading site, 15 minutes to unload and 15 minutes to re-load at the plant and you are looking at an hour and a half round trip for each truck.
If they have 2 trucks unloading at all times with a 1.5 hour cycle time, they are running at least 12 trucks, probably closer to 14-15 trucks.
Mathews Ready Mix yard screenshot from Google Street View showing their paint scheme:
OrovilleMathewsReadyMix.PNG

Aaron Z
 

jman0war

New Member
why would these videos be subject to a take down?
Surely there's a public right to know what is occurring at a publicly owned facility that could threaten the safety of....the public?
 

aczlan

Member
why would these videos be subject to a take down?
Surely there's a public right to know what is occurring at a publicly owned facility that could threaten the safety of....the public?
Whoever shot the video owns the copyright for the video and can ask Youtube to take it down.

Aaron Z
 
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