Paying for the Oroville Dam repair

[Xema]

You’ll recall that in Feb 2017 the reservoir behind California’s Oroville Dam filled, making it necessary to discharge lots of water. Due to questionable design, the main spillway developed cracks that soon became a large spillway rupture. Water discharge was transferred to the emergency spillway, which quickly proved badly inadequate - water simply roared down the face of the dam, causing massive erosion. Discharge was transferred back to the damaged main spillway, and 188,000 people living downstream were evacuated. There was never a threat of the dam itself fully failing, but the worst case could have been a severe flood. There was much additional erosion near the damaged main spillway, but no massive flood developed and the evacuation order was lifted after a couple of days.

Major repairs began as soon as practical. These were initially estimated to cost around $500 million, but with work mostly complete the total now looks to be around $870 million.

The California DWR (Department of Water Resources) assumed that FEMA (Federal Emergency Management Agency) would cover 75% of this cost, as is apparently normal in the case of natural disasters. But, as this article notes, FEMA seems less than fully eager to step up. The two agencies’ positions can be briefly summarized as follows:

CDWR: Natural conditions (too much snow and rain) led to a serious problem with our dam. The cost to repair this looks like $870 million - please pay the share (75%) that FEMA normally does when natural disasters cause economic loss.

FEMA: Your dam was supposed to be designed to handle expected amounts of precipitation. Events and subsequent analysis show that it clearly wasn’t. The resulting economic losses are a consequence of poor design and maintenance, not natural disaster. Further, our obligations in case of genuine natural disasters is to restore things to their pre-disaster state, not to pay for a massive upgrade.

Even 25% of the repair costs would be a considerable burden for California water customers. 100% would be quite painful.

[What_Exit]

It seems FEMA is correct in conserving its money for actual natural disaster relief, the problem with that theory is all the prior examples of FEMA helping out in areas where protections were clearly under-designed or not maintained. Specific examples for Sandy & Katrina are fairly easy to think of. Many of the houses on the New Jersey barrier islands should exists only at the owners peril. Some of the dikes and pumps in New Orleans were built incorrectly and/or not maintained which led to greater flooding and a greater need for FEMA’s help.

Why is the line in the sand finally being drawn for this Dam? Was the incompetence grosses than normal with this dam?

[48Willys]

Just a guess, is FEMA broke due to “disasters” like Katrina?

[running_coach]

@What_Exit

Why is the line in the sand finally being drawn for this Dam? Was the incompetence grosses than normal with this dam?

California didn’t vote for Trump. There was little said for the wildfires, also.

[jz78817]

@running_coach

California didn’t vote for Trump. There was little said for the wildfires, also.

32% of it did.

[running_coach]

@jz78817

32% of it did.

Not enough. All Trump sees are electoral votes.

[Xema]

@What_Exit

Was the incompetence grosses than normal with this dam?

Arguably, yes.

AIUI, analysis concluded that the main spillway was seriously under-designed and did not take proper account of the nature of the underlying soil and rock. The emergency spillway was close to a joke: at even a small fraction of the flow rates it would need to handle, massive erosion of the dam face was inevitable - it was pretty much a case of “15 minutes after you start using it, you’ll be desperate to stop.”

These defects were noted multiple times over the course of many years, but the warnings were never acted upon.

[jz78817]

@running_coach

Not enough. All Trump sees are electoral votes.

ah, I didn’t catch the meaning.

[aceplace57]

I’m not confident the Orville Dam’s design flaw has been fixed.

They fixed the flood damage. But what happens the next time the reservoir fills and they use the spillway?

Is FEMA supposed to pay indefinitely for a terrible design?

[HurricaneDitka]

@aceplace57

I’m not confident the Orville Dam’s design flaw has been fixed.

They fixed the flood damage. But what happens the next time the reservoir fills and they use the spillway?

Is FEMA supposed to pay indefinitely for a terrible design?

In theory the main spillway is on a much more solid foundation now. There are lots of pictures of the damage and repairs here. I’m fine with letting California pay for this themselves. Sorry your dam management sucks.

Oroville was a bit of a perfect storm in which basically everything that could go wrong did (except that they managed to avoid completely eroding away the hillside underneath the emergency spillway, which was a big win).

[running_coach]

@HurricaneDitka

In theory the main spillway is on a much more solid foundation now. There are lots of pictures of the damage and repairs here. I’m fine with letting California pay for this themselves. Sorry your dam management sucks.

Oroville was a bit of a perfect storm in which basically everything that could go wrong did (except that they managed to avoid completely eroding away the hillside underneath the emergency spillway, which was a big win).

And yet the poor building decisions/wetlands management in Houston didn’t matter.

[HurricaneDitka]

@running_coach

And yet the poor building decisions/wetlands management in Houston didn’t matter.

Here is an AP article from last year:

Six months before rushing water ripped a huge hole in a channel that drains a Northern California reservoir, state inspectors said the concrete spillway was sound. As officials puzzle through how to repair it, federal regulators have ordered the state to figure out what went wrong at Oroville Dam.

Earlier inspection reports offer potential clues, including cracks on the spillway surface that could either be cosmetic or indicate deeper problems. In recent years, construction crews patched cracks — including in the area where water burrowed a huge pit last week. If past repairs were not done properly, water could infiltrate and eventually tear through the concrete.

…

Inspectors with the state agency that both operates and checks the dam, the nation’s tallest at 770 feet, went into the half-mile-long spillway in 2014 and 2015 and did not find any concerns.

“Conditions appeared to be normal,” the inspector wrote in reports from both years.

Getting into the channel affords both a closer view of cracks as well as a chance to tap it with a special hammer, with the sound telling a trained ear whether the concrete is solid or there may be erosion in the earth below. Last August, a team of inspectors only checked the channel from vistas around it, not inside. They concluded that everything looked fine.

…

Experts said problems like the cracks in the concrete spillway and spots in nearby areas where water seeped from the reservoir through a hillside were common issues with dams. What mattered, said John Moyle, New Jersey’s director of dam safety and flood control, was whether dam operators dealt with the problems carefully — patching cracks so they were watertight, and dealing with spots where water was leaking through so they didn’t grow to undermine the concrete.

The Department of Water Resources declined to answer specific questions about the repair work, saying engineers were focused on ensuring public safety.

Robert Bea, professor emeritus of civil and environmental engineering at University of California, Berkeley, said it’s “obvious those repairs didn’t work.”

“We don’t have details on the repairs, but they put cement into the cracks and troweled it over,” Bea said. “I call it ‘patch and pray.’”

…

Was there something approaching this level of negligence in Houston?

[newme]

@HurricaneDitka

Here is an AP article from last year:

Was there something approaching this level of negligence in Houston?

Would this count? How Harvey Hurt Houston, in 10 Maps | ProPublica

In the 1940’s, the U.S. Army Corps of Engineers built two flood control reservoirs on what was mostly empty prairie about 20 miles west of downtown Houston. That system worked well when the reservoirs were surrounded by prairie and rice fields. But in recent decades, development has encroached from all sides. And, in fact, about 14,000 homes are actually located inside the reservoirs…During Harvey, when more floodwaters accumulated behind the dams than ever before, 5,138 of those homes flooded.

You’ve got 5000 flooded homes, built in the floodplain of a flood control reservoir. If these houses on average are worth $200k, it would cost $1 Billion to buy them all out and turn it into green space.

[running_coach]

@HurricaneDitka

Here is an AP article from last year:

Was there something approaching this level of negligence in Houston?

The basic were that Houston ignored the need for the wetlands and drastically overbuilt. The wetlands act as a sponge in severe storms. Without them, the flood waters had nowhere to go.
Houston’s flooding shows what happens when you ignore science and let developers run rampant

Since Houston, Texas was founded nearly two centuries ago, Houstonians have been treating its wetlands as stinky, mosquito-infested blots in need of drainage.

Even after it became a widely accepted scientific fact that wetlands can soak up large amounts of flood water, the city continued to pave over them. The watershed of the White Oak Bayou river, which includes much of northwest Houston, is a case in point. From 1992 to 2010, this area lost more than 70% of its wetlands, according to research (pdf) by Texas A&M University.

In the false-color satellite images below, plants and other vegetation appear green, while urbanized and developed areas appear blue and purple. Drag the slider to see how northwest Houston has changed since 1986.

[carnivorousplant]

Hoover dam had a spillway erode in the 1980s. I wonder if it is a common failure.

[HurricaneDitka]

@carnivorousplant

Hoover dam had a spillway erode in the 1980s. I wonder if it is a common failure.

I just took the tour of Hoover Dam on Saturday. They didn’t mention this part, but now I’m intrigued. There was nothing obvious there that even remotely resembled the Oroville’s main spillway. There were a couple of what-appeared-to-be emergency spillways on either side though.