Emergency: California’s Oroville Dam Spillway Near Failure, Evacuations Ordered

Breitbart ^ | Feb 12, 2017 | Joel B. Pollak1

[janetjanet998]

The California Department of Water Resources issued a sudden evacuation order shortly before 5 p.m. Sunday for residents near the Oroville Dam in northern California, warning that the dam’s emergency spillway would fail in the next 60 minutes.

The Oroville Dam is the highest in the nation.

[Ray76]

green spots answered last night at #OrovilleSpillways public meeting. “There is no leak in the dam,”

https://twitter.com/CA_DWR/status/859882796218765314

[Ray76]

The green spot is from rain, said Christy Jones, deputy director of statewide emergency preparedness and security for DWR.

“When the rain falls, the grass grows. There is no leak in the dam,” she said.

DWR has looked at this green spot many times, continued Joe Royer, an engineer with the department.

http://www.chicoer.com/general-news/20170502/questions-answers-and-a-bit-of-scorn-for-dwr-at-oroville-meeting

[abb]

http://www.chicoer.com/general-news/20170502/questions-answers-and-a-bit-of-scorn-for-dwr-at-oroville-meeting

Questions, answers and a bit of scorn for DWR at Oroville meeting

By Heather Hacking, Chico Enterprise-Record

Posted: 05/02/17, 11:00 PM PDT | Updated: 3 hrs ago

• The “green spot” on the dam, will that cause the dam to fail? That’s another question that has been circulating through people who live in Oroville.

The green spot is from rain, said Christy Jones, deputy director of statewide emergency preparedness and security for DWR.

“When the rain falls, the grass grows. There is no leak in the dam,” she said.

DWR has looked at this green spot many times, continued Joe Royer, an engineer with the department.

snip

[abb]

That is a @##d!!ned insult. What the hell did the rain do? Rain only in that one spot?!?!?!?!

[meyer]

“”The green spot is from rain, said Christy Jones, deputy director of statewide emergency preparedness and security for DWR.

“When the rain falls, the grass grows. There is no leak in the dam,” she said.

DWR has looked at this green spot many times, continued Joe Royer, an engineer with the department.””

Given the significance of the sequence of events that could occur if they were wrong, I’d demand a second opinion.

[Ray76]

It’s pretty amazing. My eyes popped when I read it.

[Jim W N]

Who told Christy Jones to say that?

[Jim W N]

Wonder who propped up Christy Jones so they could hide behind her? Images of the Islamofascists hiding behind the women and children so the terrorist-perps don’t get shot. These government officials have learned a lot from their Islamic buddies.

Does anyone believe this lady has any idea about what she’s talking about? Oroville residents should be up in arms maybe literally.

ER hope you’re doing OK after hearing this one. Somebody needs to get a bullhorn and blast/broadcast what is really going on here and what the ACTUAL threat is here (”pre-failure condition”.)

[janetjanet998]

I thought it was a natural spring LOL

did she mean the rain runoff from that “spring”

must be very isolated showers since it only falls in one spot

[Ray76]

DWR is still looking for a PR person at Oroville

https://twitter.com/CA_DWR/status/858127066973184001

[EarthResearcher333]

I read this story about midnight last night. I too was wondering why a non-engineering person (Christy Jones) was giving answers to this in such a simplistic answer of "it rains" & "grass grows" - yet have the engineering authority to definitively state "there is no leak in the dam".

I envisioned a rain cloud that hovered over the green area...

Any savvy press reporter would recognize that these factors (person's skillset, non-engineering, facile reason, definitive conclusion, and DWR mgmt choosing this person to answer) are entering into the "surreal" zone.

DWR has now set themselves up for an engineering knowledgeable article that will disassemble their town hall statements & make them look incompetent to the public over this leakage issue. Just wait.

[meyer]

DWR is still looking for a PR person at Oroville

They couldn't pay me enough. Besides, I'd have to lie like a Clinton to do that job.

[Jim W N]

Man, I can’t wait. I hope they get what’s coming to them in enough time for those living below this giant pre-failure catastrophe-in-waiting.

[meyer]

did she mean the rain runoff from that “spring”

Or did she mean that it rains, causing the reservoir to rise to a point where water can begin to seep through the dam and provide water to the other side. I mean, seepage through the dam is caused, ultimately, by rainfall (and snow melt).

[PavewayIV]

The more I look at your picture of the trench for the impervious core, ER333, the more I have to believe the original engineers made the same mistake they did on the spillway. They cut down to 'mostly' unweathered bedrock, but just filled in or ignored seams of weathered rock if they looked solid. If I look at that picture, I do not see a continuous bed of solid, contiguous bedrock suitable for the impervious layer's foundation. I see the same kind of geology that we see under the spillway and emergency spillway apron: a folded, marbled-like mixture of 'good' green and 'bad' weathered/oxidized bedrock. They may have filled in imperfections with compacted fill (like under the spillway) but that's not likely good enough

Between the solid concrete core block and pressure and settling of the clay middle of the dam, this shouldn't have been a problem. Way up the slope, to the left of your "700ft shallow slope" label would be a problem. Not to mention that the trench bed seems particularly scrappy at that level. Hard to tell from the dam blueprints that have surfaced, but I believe the impervious core is also thinner as you go up the abutment.

I have to wonder if the 'natural spring' is actually water piping under or around the impervious core at 700' or higher. This would lead to the engineer's odd observation about 'natural spring'. Sure, because it looks like the water is coming from the rock wall of the abutment. But it's reservoir water infiltrating under or around the impervious core.

This itself isn't a colossal problem. Dam engineers have been grouting imperfections in foundation rock for decades on many dams. It's fixable if you keep on top of it. The problem is if DWR engineers ignore that possibility and "monitor until just before failure" like they did with the emergency spillway.

Kind of makes one wonder about the 'contract issues' that made them let the other geologic engineer on the forensic team go. If he told them the whole dam suffered from the same geologic problems that the spillway had, then the easy fix is to replace him with someone that thinks differently, i.e., "Everything is fine - the rock is great. Let's get that half-designed spillway built NOW!"

The bigger problem that might also (or alternatively) be lurking underneath is the penstocks and diversion tunnels. If there has been erosion around the outside of those (not uncommon), then there may be voids and settlement problems inside the dam fill. If DWR has been too cheap to use ground-penetrating radar to check the spillway for hidden voids, then they sure as heck probably have never checked the penstocks and diversion tunnels for hidden voids. They don't even seem to be particularly concerned about missing monuments or thoroughly measuring settlement. And how, pray tell, does a geometry monument marker on a dam go missing?

[EarthResearcher333]

"They cut down to 'mostly' unweathered bedrock, but just filled in or ignored seams of weathered rock if they looked solid. If I look at that picture, I do not see a continuous bed of solid, contiguous bedrock suitable for the impervious layer's foundation. I see the same kind of geology that we see under the spillway and emergency spillway apron: a folded, marbled-like mixture of 'good' green and 'bad' weathered/oxidized bedrock."

Hi PavewayIV, Engineers drilled and pressurize filled grout into the continuous seam of the center of the trench (centered in the core fill). In fact, the Grout Gallery Tunnel has a purpose of being able to inspect and detect "piping" leaks from the grout curtain seal. This tunnel allows access to repair drilling and fixing to any grout curtain issues over time.

You are correct about the "weathered rock" in places. However, the image resolution is unable to determine this degree along the future core centerline.

IF there were a "piping" of the reservoir at 700ft or higher to infer a form of a "spring", fluid flow hydraulic dynamics would have a curvature of Zone 3 shell moisture if any. In other words, the water would flow along the surface of the rock abutment, with a small amount possibly in the sharper transition slope via capillary action - yet it still would be a tight downward curvature.

Yet, the Greening follows a long horizontal and upward tilting line. No spring at the abutment can cause this effect.

As far as the Forensic Team member: there could have been circumstances that came up which required the person to find themselves unable to commit to the intense work load (family, job, etc). Because the letter is vague in a reason, there is not enough information to discern. I suspect information will come out later as the press will be looking into this.

Penstocks & diversion tunnels: Proper inspections will use hammer pings for soundings in void detection. I'm not so concerned about the deeper rock tunnels. But the Palermo Outlet tunnel was inspected using an ROV. Not sure what type of instruments were on this to check for voiding. The tunnel should be in a depth area of competent rock.

[EarthResearcher333]

Why Engineers are stumped - Seasonal Rains - Consolidation - Multi-year sectional layers - Diff Settlement => Green wet area?

Oroville dam is so large that the construction process required the dam to be built in large sectional layers each year. During Seasonal Rains, any exposed finished surface layer of these sections would experience a combined "consolidation" effect from settlement and moisture extrusion. Consolidation will densify any soil grains or small fill more than regular "compaction" (compaction is compressing fill material to remove the air - consolidation is compressing water out of fill which leaves a closer packing of soil grains, leading to increased density [decreased compressibility] and decreased permeability (more resistant to water flow)).

The main Oroville dam was constructed in stages where it had a "hump" along the toe axis in 1964, then layers 1, 2, and 3 emplaced in years 1965, 1966, and 1967 respectively. Because of the exposure to seasonal rains during this phased construction sectional layering, a unique effect of potential densification from consolidation & settlement would have created "horizontal" seams. These seams have been key to understanding the Green Wet Area. More Later.

[EarthResearcher333]

Drain Gauge paint striping revealed - Workers preparing for new round of core sample drilling into Upper Main Spillway - Milky Water & Foam to come?

Other pics in the image gallery note yet another large concrete pipe bridging construction point at a ravine and also a culvert being placed. All of this for "Burma Road". Wherever Burma Road is going, we'll have to wait to see. It looks like they are building a new access road as anticipated on the north side of the Feather river.

[Ray76]

Re: "Burma Road"

I've been looking at some hiking/biking/kayaking websites and Burma Road is an alternate name for the Brad Freeman Trail along the north side of the Thermalito diversion pool. It follows the river bank between "A" and the MS.

The existing road is being upgraded.

Some DWR photos of improvements:

Workers prepare rebar and concrete forms at the two barrel culvert at Morris Ravine for the Burma Road crossing

Source: https://pixel-ca-dwr.photoshelter.com/galleries/C0000OxvlgXg3yfg/G00003YCcmDTx48Y/I00000hdlszB.BJo/DK-oroville-spillway-8769-05-03-2017-jpg

 

Finishing touches to the three barrel culvert under Burma Road at Oregon Gulch

Source: https://pixel-ca-dwr.photoshelter.com/galleries/C0000OxvlgXg3yfg/G00003YCcmDTx48Y/I0000AkYshWk3WQY/DK-oroville-spillway-8711-05-03-2017-jpg

A small pond at the beginning of Burma Rd, at 'A', has been partially filled in so that heavy equipment may pass.

Source article: http://www.chicoer.com/article/NA/20170301/NEWS/170309976

[Ray76]

Sources for the Burma Road is an alternate name for the Brad Freeman Trail claim

http://lincolnhillshikers.org/Hikes/BurmaRoadTrail.html see driving directions

http://trails.mtbr.com/cat/united-states-trails/california-trails/california-all-other-areas/trail/burma-trail-and-downhill/prd_165045_4518crx.aspx