Workers use leaf blower to seal leaks on billion $ spillway

By Tim Lantz, iHear Media

AENN

An engineer with 20-plus years experience working on dams fears the Oroville dam could be in trouble again. He says the same problem which led to the failure of the main spillway in 2017 is still happening.

March 15, 2019 picture of the Oroville Dam spillway. Note water seeping from the same area where the original spillway broke apart on February 7, 2017. Photo: Robert Armstrong AENN Copyright 2019

The state has spent more than a billion dollars rebuilding the main and emergency spillways at Oroville dam. Now, expert Scott Cahill told News Radio KFBK, water can be seen seeping from the foot of the dam and dozens of points along the new spillway.

An hour later from the above picture taken on March 15, 2019 a second picture of the Oroville Dam spillway shows workers about to repair the water seeping from the same area where the original spillway broke apart on February 7, 2017. The workers are about to engage in what noted dam expert Dr. Robert Bea calls “patch and pray”. meaning “Patch” the leaking seams that are venting water under high pressure from behind the spillway roller compacted concrete and 2 1/2 foot thick steel reinforced structural concrete slab then “Pray”. Next to the seated worker is a “leaf blower” that is about to be used to blow water from a leaking seam so the workers can “Patch” the leak.. These high pressure water leaks are in the exact same spot as the original leak that caused the rupture of the main spillway on February 7, 2017. Photo: Robert Armstrong AENN Copyright 2019

“That concrete spillway slab is now moving water, which is evolving up through the slab today,” Cahill told News Radio KFBK. “Very similar to what it did before the failure (in 2017).”

Workers prepare to use a leaf blower to dry leaking seams on the Oroville Dam main spillway. March 15, 2019.

Workers using a leaf blower to dry leaking seams on the Oroville Dam main spillway. March 15, 2019.

Cahill has seen this with his own eyes. He’s even more concerned with cracks in the gates along the crest of the dam, something he says is already in what he calls failure mode.

“The possibility exists that a cutback will occur there that will allow the pool to release,” Cahill insisted. “At that point we’ll no longer have control over the velocity or the amount of water that’s moved downstream.”

Cahill said he has sent his concerns to the California Department of Water Resources, but he claims those officials have not replied.

Paul Preston interviewing dam expert Scott Cahill April 23, 2917 at the Oroville dam. Note the credentials displayed by Paul Preston and the yellow vests and helmets worn by Preston and Cahill. Per Department of Water Resources policies at the time members of press and researchers were required to sign in and register at the DWR headquarters on Glenn St. near the dam on February 12, 2017.

The Oro Dam location where the above picture was taken was a restricted area by the DWR and could only have been accessed with the approval of the DWR and anyone in this area were required to wear a helmet and yellow vest. These rules were strictly enforced by the DWR. Preston and Cahill both registered, wore the appropriate safety equipment and were given access to areas of the dam not afforded to to the general public. In comments to KFBK DWR spokesmember Erin Mellon “suggested Cahill may have never set foot on the dam”. Overwhelming evidence suggests Mellon to be wrong.

The DWR issued a statement to a KFBK request for comment on Cahill’s claims.

“DWR is confident in how we have repaired and reconstructed the main and emergency spillways, using the best engineering practices available and with constant oversight by state and federal regulators to ensure the safety of the downstream communities the facility protects. DWR and its construction contractor Kiewit worked on the design and construction of both the main emergency spillways under the oversight and with the approval of an independent Board of Consultants and state and federal regulators,” said spokeswoman Erin Mellon. “DWR is aware and anticipated some water to seep through the main spillway gates this winter. As the reservoir surpasses elevation 813 feet (the elevation of the spillway gates), some water does seep through the gates onto the spillway as the gates are not designed to be water tight. We issued a press release anticipating this on March 5. It has also been reported on in previous years.

Mellon also suggested Cahill may have never set foot the dam.

A panoramic aerial view of the Oroville Dam main spillway taken Sept. 29, 2017 shows the gap in the middle where roller-compacted concrete was used, and work above and below it where steel reinforced structural concrete was placed. The entire center section was resurfaced with structural concrete. The center section shown above is where the roller compacted concrete was used and was the area of the original leakage that led to the rupture of February 7, 2017 This is now the same area where the leakage has reappeared in March 2019. (Kelly M. Grow — Department of Water Resources)

“DWR and Kiewit maintain records of visits to the dam and spillways and have no record of Mr. Cahill visiting the facility. As you know, the dam and spillway have been inaccessible to the public during reconstruction. I do have an email from a member of the public saying he visited the Oroville area at the end of April 2017 but as you know, that was well before reconstruction began.”

Erin Mellon Should Not Be Critical of Scott Cahill

Reconstruction was already underway when Cahill visited the dam in mid April 2017 and had already spent several days either at the dam or in interviews with DWR/dam personnel, federal, state, county and city officials.

Prior to his visits to Oroville Dam Cahill was actively engaged in the investigation as to the reasons for the failure of the dam system with federal officials and was making attempts to reach our and work with California state officials in the legislature, DWR and various local officials. Federal officials and several state legislators and local officials were more than happy work with Cahill. Not surprising the California state Department of Water Resources refused to entertain any relationship with Cahill.

The contractor Kiewitt was given $275 million contract to repair Oroville Dam Spillway in early April of 2017 and had been meeting with DWR officials to make the necessary repairs before the signing of the contract.

“Per the agreement, Kiewit is to begin reconstruction on Oroville’s failed spillways immediately, with the goal for the system to be operational before the region’s wet winter season that traditionally begins in November”.

Kiewitt did in fact make an immediate transition into working on the dam as early as April 12, 2017.

Cahill in early April before the Kiewitt contract was let made arrangements to fly from Virginia to California witness for himself the disaster first hand. Cahill through his own investigations and interviews knew all the intimate details of what needed to be done but also knew of the serious flaws in the DWR’s planning and execution of the necessary repairs needed to make Oroville dam safe.

Cahill has long been a critic and a pain in the side of the California Department of Water Resource’s handling of the Oroville dam disaster. In an August 2017 interview on the Chris Martenson’s Peak Prosperity podcast Cahill gave several warnings about what he saw at the dam were major issues and the subsequent irresponsible handling of the crisis by the DWR which have not either been addressed or mitigated still to this day.

“They’ve begun the repairs on the bottom half of the spillway, but the tragedy and loss from the bottom half of the spillway failing has already been realized. No one is worried about the bottom half of the spillway. On the other hand, they’ve done nothing yet with the upper half of the spillway — which is what would cause a catastrophic failure of the dam. It’s amazing how much money they’ve already spent, and yet their priorities are such that they haven’t abated the liability at all.

So yes, we’ve made the bottom of the principal spillway, the concrete slues, more sound. But it’s not the bottom of the dam that will fail, of course, it’s the crest — the top of it — where the gates are. That’s still highly suspect.

There are additional issues involving the unwanted moving of water through the dam — the so-called “green spots”. These are areas where water is migrating through the dam, probably through the indigenous soils adjacent to it. I’ve walked on these [at Oroville] and you can stick your foot down, and like your backyard after a torrential rain, water actually comes up into the footprint after you remove your foot. This is not a good situation. I believe there is a lot of movement of water through that dam, including at the structure itself that houses the gates that control the flow down the principal spillway.

There’s nothing wrong with embankment dams in general, they’re wonderful dams. But they rely on the mass of the earthen embankment itself to offset the forces that try to slide or rotate it into failure. When we see water migrating through a dam, it can potentially cause failure of the dam because it offsets the mass all that earth. Plus, there’s a lot of river rock and sand in this embankment. River rock, as we all know, is round. Anyone can understand how a pile of round rocks, if the fines have been washed out from between them by water and the rocks then vibrated, for instance, by seismic activity, weakens the system. These concerns are very, very serious. I believe that this situation is occurring in multiple places across the Oroville dam — and yet this is simply not being discussed”.

Why should Erin Mellon not be critical of Scott Cahill? Simple Erin Mellon has no credibility when it come to issues of dam safety or even dams in general. Mellon who inferred that Cahill had not been to the dam in her interview with KFBK falsely did so because she did not know the facts.

Mellon whose official title is Assistant Director of Public Affairs, California Department of Water Resources was not even employed by the DWR until August 2017 three full months after construction of the spillway was underway by Kiewitt.

Mellon had zero experience working on issues of dams when she was hired in August of 2017. Today following numerous town halls in the affected area of the dam and the inundation zone Mellon has shown herself to be a major liability. Trumpeting the false narrative associated with the safety of Oroville dam being pushed by the Department of Water Resources Mellon has become a good fit. Following a town hall in Yuba City, CA one walnut farmer stated: “She’s (Mellon) is a bald faced liar”. Unfortunately for Mellon the walnut farmer’s comment is what the public generally says about her and by extension the DWR.

The world of dam safety has the highest regard for Scott Cahill and others who have been critical of the DWR including Dr. Robert Bea from the University of California, Berkley. Dr. Bea, a co-author of a report warning of a green spot near the Oroville Dam in July 2017 is a professor emeritus of engineering at Berkeley called the complete repair of the Oroville dam spillway is nothing more than “Patch and pray operation”.

Its obvious we all need prayer as the “patches” are not holding.

An aerial photo of the Oroville Dam main spillway before the 21/2 foot steel reinforced structural concrete was placed over the top of the roller compacted concrete. Wet streaks on the roller compacted part of the chute, are evident but the Department of Water Resources said is was “expected”. April 6, 2018 Photo by Gonzalo (Peewee) Curiel. Les than a year later water is now seeping through both the roller compacted concrete and the steel reinforced structural concrete.

Below is a list of references The DWR and their spokesmember should consult:

‘Patch and Pray’ Crack Repairs on Oroville Dam Emergency …www.nbcbayarea.com/news/Patch–and-Pray-Crack…’Patch and Pray’ Crack Repairs on Oroville Dam Emergency Spillway: UC Berkeley Civil Engineer … and troweled it over,” Bea said. “I call it ‘patch and pray.”’ … who went to Oroville Dam in …
Cracks may offer clues to California dam’s troubles …static-ssl.businessinsider.com/…may…dams-troubles-2017-2″We don’t have details on the repairs, but they put cement into the cracks and troweled it over,” Beasaid. “I call it ‘patch and pray.'” Water gushing from the Oroville Dam‘s main spillway on Tuesday in Oroville, California. AP Photo/Marcio Jose Sanchez
No More Patch and Pray—Privatize Oroville Dam: News: The …www.independent.org/newsroom/article.asp?id=9289No More Patch and Pray—Privatize Oroville Dam … (Oroville Dam main) spillway,” Bea said. … with its opaque patch-and-pray approach to maintenance and public …
California dam cracks were repaired by ‘patch and prey …www.dailymail.co.uk/news/article-4226368/Cracks…The Oroville Dam is to be soaked by a foot of rain by Tuesday, ramping up the pressure on engineers who are frantically trying to repair ‘patch and pray‘ quick-fixes which led to its near-collapse …
No more patch and pray — privatize Oroville Dam – SFChronicle.comwww.sfchronicle.com/opinion/openforum/article/No…No more patch and pray — privatize Oroville Dam. … No more patch and pray — privatize Oroville Dam. … (Oroville Dam main) spillway,” Bea said.
Cracks may offer clues to California dam’s troubles …www.businessinsider.com/ap-cracks-may-offer…”We don’t have details on the repairs, but they put cement into the cracks and troweled it over,” Beasaid. “I call it ‘patch and pray.'” Water gushing from the Oroville Dam‘s main spillway on …
Oroville – The More We Learn, The … – The Hugh Hewitt Showwww.hughhewitt.com/oroville-learn-worse-getsIt ain’t over yet: California’s crumbling Oroville Dam will be hit by a FOOT of rain as engineers race to repair erosion after years of ‘patch and pray’ quick-fixes. There is a lot of coverage out there with such attention grabbing headlines.
Report: State, Feds ‘Negligent’ in Oversight of Oroville Dam …www.kqed.org/news/11579545/oroville–dam-spillway…Analysis accuses agencies of relying on a ‘patch and pray‘ approach that led to spillway crisis in February. … Oroville Dam‘s main spillway pictured on Feb. 13 …
Legislative Oversight Testimony Report: Oroville Damwww.orovillechamber.com/wp-content/uploads/2017/…E-MAIL: bea@ce.berkeley.edu BERKELEY, CALIFORNIA 94720-1710 Legislative Oversight Testimony Report: Oroville Dam Dr. Robert G. Beaa Emeritus Professor, Department of Civil & Environmental Engineering University of California Berkeley May 11, 2017 Acknowledgements
Analysis Cites Flawed Management in Oroville Dam Failureswww.materialsperformance.com/…/10/…oroville–dam-failures“A superficial ‘patch and pray’ approach is not an acceptable safety and risk management process for important public infrastructure systems,” Bea says, adding that state agencies should have upgraded the Oroville Dam facilities beforehand while also taking steps to update the design, construction, operating, and maintenance standards.