What Really Happened at the Oroville Dam Spillway?
February 2017 saw one of the most serious dam-related engineering incidents in history with the failure of the service spillway at Oroville Dam. Whether they realized it or not, the people living and working downstream of Oroville Dam put their trust in the engineers, operators, and regulators to keep them safe and sound against disaster. In this case, that trust was broken. This video provides a summary of the event, including an explanation of the engineering details behind the failure.
Update: Watch the video about rebuilding the spillways here: • Rebuilding the Orovill...
Independent Forensic Team Report: damsafety.org/sites/default/f...
Watch this video and the entire Practical Engineering catalog ad-free on Nebula: go.nebula.tv/practical-engine...
Practical Engineering is a KZhead channel about infrastructure and the human-made world around us. Hosted, written, and produced by Grady Hillhouse. We have new videos posted regularly, so please subscribe for updates. If you enjoyed the video, hit that ‘like’ button, give us a comment, or watch another of our videos!
CONNECT WITH ME
____________________________________
Website: practical.engineering
Twitter: / hillhousegrady
Instagram: / practicalengineering
Reddit: / practicalengineering
Facebook: / practicalengineergrady
Patreon: / practicalengineering
SPONSORSHIP INQUIRIES
____________________________________
Please email my agent at practicalengineering@standard.tv
DISCLAIMER
____________________________________
This is not engineering advice. Everything here is for informational and entertainment purposes only. Contact an engineer licensed to practice in your area if you need professional advice or services. All non-licensed clips used for fair use commentary, criticism, and educational purposes.
SPECIAL THANKS
____________________________________
Stock video and imagery provided by Getty Images, Shutterstock, Pond5, and Videoblocks.
Much of the footage and photographs used in the video were created by the California Department of Water Resources. Use of these works in the video is done in accordance with the California Public Records Act.
Music: "Tonic and Energy" by Elexive is licensed under a Creative Commons Attribution License. Source: • Elexive - Tonic and En...
Music: "Moon and Star" by Wintergatan. This track can be downloaded for free at www.wintergatan.net. Free license to use this track in your video can be downloaded at www.wintergatan.net.
Producer/Host: Grady Hillhouse
Assistant Producer: Wesley Crump
Moving water never ceases to surprise me with its raw power.
No kidding. Though I suspect this is more dramatic than usual because they built spillways designed to sit on granite on top of loose soil instead. But even granite can't stand up to the awesome power of water forever.
And yet, way too many people underestimate it every day. Flash floods, low head dams, Delta P, all of it. Will kill you. But, "its just water, how dangerous could it be?" I'd rather not find out "just" how dangerous it can be, thank you.
just a cubic metre of water is a metric tonne (~35 cu ft. to 1.1 US ton). hitting a wall makes it stop in less than a mm of space. for just 1m/s (~2.2mph) that's over 1000 tonnes equivalent of force.
I’m going to crack a ‘dad joke’ now, but should water have _roar_ power, as it makes a roaring noise 😋🤪 I’ll get my coat!
How high does a swiftly moving stream need to be to knock you off your feet? You are down long before it gets knee deep.
It’s unfortunate when your emergency spillway is in itself an emergency
Yes, but I would have done the same thing they did. Tried to use the emergency spillway for what it was nominally designed for until it became apparent that it couldn't sustain further use.
@@thorr18BEM if I recall, they used the emergency spillway only because they had flow restocked down the main spillway to keep damage lower. Once the erosion on the emergency spillway was proving to be dangerous to the entire dam structure, they let er rip down the main spillway as it could handle far more erosion before the integrity of the dam was in danger. The bedrock and natural plunge pool were very stable after a while
A cascade of errors (pun intended).
It's seams like our government did us dirty they were faced with a decisions of either risk flooding thousands of homes or flood a hydropower plant. It seams like there is more to this than just some engineering mistakes and I know this sounds like a conspiracy theory but knowing the track record of our public engineers it's not super unlikely that these people had $$$ in their eyes from the very start and didn't care about safety
@littlejack59 the problem isn't money when you flood the hydropower plant, the problem is you risk flooding the power lines which powers the dam, which means you can no longer control the spillways and risk flooding the entire countryside anyway.
I used to be a spillway designer. I have designed the structure of several major dams' spillways. It was a very good presentation of the problem, with enough explanation for the laymen to understand the issues at hand. Just by looking at the damaged structure, I could see that the thickness of the slab was far less than the current practice. The lack of shear keys and keyed foundation was another thing that I found interesting. During the design process, it's easy to look at a slab sitting on the ground and thinking "nothing is going to happen!", but careful analysis always shows that you can never underestimate the effect of uplift, and trusting the drains is always risky. They can get clogged, and monitoring the discharge of the drains is not enough to assess the effectiveness of the drainage to lower the uplift forces, because the a local clogged drain can result in a local failure, and any local failure in a spillway will result in a total failure of the structure.
Hmmm your description reminded me of the explanation that NASA management tried to give about the shuttle Challenger safety factors.
@@kbanghart "tried" is the keyword here, lol. I will be happy to elaborate, and I will be happier if I can succeed in more than just "trying" the next time. Thanks, I appreciate your comment.
@@mehdimarashi1736 just to be clear, no complaints about your comments 👍
How did you not notice the lack of rebar in the broken spillway? There should be rebar sticking out all over. Before they poured the concrete for the new spillway the rebar was so thick you could not see through it.
@@phillipkalaveras1725 It's one of those things that even when you see it, you don't believe your eyes. Since the slab is not supposed to be a subject to much bending, the only rebar needed is a minimum required to prevent cracks due to shrinkage and thermal expansion/contraction. Those rebars are visible in the drawings (e.g. 13:39), but I can't see them in the broken spillway. I still think that they are there, but for some reason they are invisible. They wouldn't have helped, though. Since the new slab is super thick, it needs more shrinkage/temperature rebars. The amount required is proportional to the slab thickness. There might have been other design considerations, too; but I cannot guess what they might have been.
Who's here at 3am just watching these ?
I only watch his videos at night. They are cozy and put me to sleep
4 am here
2 am for me. Eastern standard time.
many
4:42am Australian Eastern Standard Time. Cuppa time.
My engineering instructor said "when a doctor makes a mistake a person dies, when an engineer makes a mistake thousands could die."
@@TweakRacer Depends how many die, if its a lot to the point someone has to take the fall in government. Engineers usually don't have much political power.
One of my engineering Profs had a daughter who was an MD. He said when a patient dies the doctor gets to blame "God's will" but when a bridge collapses, the engineer gets to go to prison.
@@JimmyJamesJ Sorry, but that's the exact opposite of what is true.
@@ev6558 I didn't say it was true, I said it's what one of my engineering Profs said. Also, there is no "opposite" of truth, truth is subjective except in pure mathematics.
@@JimmyJamesJ I didn't say you said it was true, I said it wasn't. Truth is absolutely not subjective, facts are facts and reality is reality. Are you an engineering student who is interested in facts or someone who took naps in the back row of Philosophy 101 and wants to engage in pointless mental masturbation over what's "real"? Stop grasping for straws, you repeated some nonsense someone told you to sound clever, just own it.
It’s a special kind of person that can turn 600 pages of engineering speak into something understandable and entertaining.
Yes...very well done!
as an engineering student theres a special kind of person that can bother to read a whole 600 page report 💀
@AndrewWithEase11 11 sounds like someone is jealous of keys?
@AndrewWithEase11 11 if this is toddler stuff you must make killer content. Where can I see some?
@AndrewWithEase11 11 Oh, I'm sorry. I'll work on that and get right back to you....ok? We can't all have your killer wit.
I lived in Marysville CA during this incident and had to evacuate my home. I worked at the fire department so I saw things from a different perspective during the evacuation. We were not at all prepared for this event and if the dam would’ve completely given way, a lot of us wouldn’t have made it. Thanks for the great video. We should all learn more about the environments we live in, both man made and natural.
There were 150,000 evacuees stuck on the roads. Had the dam failed, it would have been a calamity never before seen in US history. Thank your state leaders, who'd rather spend money on useless homeless bums and drug addicts instead of maintaining the infrastructure.
Preparedness is so rarely adequate. I have seen this lack so many times in my work as a safety professional. It's impossible to plan for every possible contingency, but trying to do the best you can to plan for the worst should always be the goal.
I lived in Marysville as well. Once they evacuated oroville we figured we’d do the same. We saw fights happening at gas stations and cars driving on the sides of the road to get passed the traffic. Felt like the end times.
It was never the dam that was in danger of failure, it was the erosion below the emergency spillway (not even close to the dam) that was about to cause that spillway to flip over and release vast amounts of water.
@@eily_b good point, but most people, when they hear about a problem with a dam, don't worry about those details and their mind instantly jumps to the worst case scenario.
Thank you for that. I love downstream from Oroville dam and my family and I were evacuated due to this. My husband's father has a friend who worked on the dam during original constitution and he told my husband that if they ever used that emergency spillway, it would fail, and it did.
My Dad worked on the dam. He told me the same thing about emergency overflow, never completed it. Notice now it is all covered in concrete as engineers originally designed/intended
I personally would be quite interested in a part 2 talking about the repairs and mitigations of the now known failure points
Right? For one, the design and construction of the primary spillway is probably going to be ENORMOUSLY more complex and expensive, because with all the exposed bedrock, it will have to become an aqueduct, I must imagine.
@@dionh70 They can probably just fill in with rock and build on top of that new level surface.
Yes please!
Please, this would be awesome
doesnt talk as much about mitigations, but this was a media clip filmed by the construction contractor doing repairs. kzhead.info/sun/p66Hl7uOaaCKipE/bejne.html
I live in Oroville and was present when all this was going on. It was very scary, our river was way too high spilling over into areas that were normally very safe to go in to but were suddenly considered unstable because the river level may change. It was very interesting to watch your video confirming many ideas in heated discussions between friends, family, coworkers, and other people about why the spillway failed. There was a lot of things that could have been done to prevent this from happening however it was overlooked whether by lack of money or by sheer ineptitude...whatever the reason it prompted a closer look into the safety and structure that has since been rectified and made much more stable. So in all it worked out for the continued safety of the people living down stream.
I've never had a complicated set of facts and factors described so clearly and eloquently as this video has done. I practically feel like an engineer right now! Thank you very much.
I live in Oroville and got to watch this unfold. It sure made life real exciting here for a few weeks. Please do the follow up video about the rebuild because it is massive. They re-built an entire mountain.
Im from Chico and y’all should’ve gotten swept away
@@cba976 well u should be involved in a drive by
If the ground on which the spillways were built was 'mischaracterised' might that also apply to the dam itself? Maybe it's time to find out if you haven't already investigated.
@@TweakRacer What the heck are you on about? "2734 mountains worth of legal resident tax dollars" sounds like some kind of clickbait nonsense one would see from a tabloid, and it makes no sense whatsoever.
Go to Juan Browne's blancolirio channel, complete coverage of rebuild, boots on the ground an fly overs....
I'm really loving these "What Really Happened?" videos. They're so well written and presented; not too clinical, not too casual, nothing extraneous, nothing missing
@Peter Evans That's nice, honey
@Peter Evans The 600 pages becomes necessary when you introduce a second old lady with different opinions
It's never aliens, though.
I stayed appraised of the Oroville Dam Spillway situation through the "Blanco Lirio" channel here on KZhead. Juan overflew, as permitted by the F.A.A., the dam every day, participated in the Media Question and Answer sessions and displayed and evaluated charts for us. Juan has definitely earned an "E" for EXCELLENCE for his coverage.
This is fascinating to me as I grew a couple miles from oroville dam. No one talks about it but the biggest spillway release I saw was in 1986 when so much water was released that it devastated the adjacent hillside as the water hit the detentes at the bottom of the spillway and launched it into the foliage and soil on the other side. If you look closely, there are still signs of that today. It’s very rare anyone talks of that flood year even though they maxed out the spillway or so it seemed and flooded the towns of Marysville and yuba city
My wife says you really know and love your job, when you can explain it to normal people and they understand what your saying, dude you nailed it
@@bigballz4u If you watch his previous videos, you know
@Steve Lynch - Totally agree with your wife. 😊 No dam construction experience. But I understood him surprisingly well. Even with those 2 major terms mentioned, I could figure out his diagrams/explanations. Sometimes technical things necessitate a pause & word definition lookup. I prefer Merriam-Webster for the online search results.
aren't you a little old to be caring what women think?
Your wife tells me that too
@@jeffdean4386 shut the fuck up
That stagnation pressure effect is how airplanes know how fast they’re going: they have a tube sticking out into the airstream, and measure the pressure rise in the tube.
Don't say it outloud without also spelling it for those in the UK. Learned that lesson the hard way.
Actually I was thinking about something too... If helicopters have the same setup and they fly sideways, by the venturi principle, there should be a negative pressure. Does a helicopter then register a negative forward speed/tell us that we are going backwards?
Interesting topic
@@PracticalEngineeringChannel you what?
@@PracticalEngineeringChannel I'm in the UK, and missing the connection? Only one I can think of is Air France 447, Please spell it out?
The homes and business downstream existed before Oroville Dam was constructed. There was much discussion at the time after the spillway collapsed, as to lack of maintenance and upgrading. In 1960’s when the dam was built, infrastructure money was easier to come by. Now, politics plays an enormous part of why funds to repair and replace aging structures never happens.
Exactly
Something that should never be overlooked is the qualified opinion of one or more geologists that specialize in water management. It could have saved a lot of worry in the people who live downstream from the lake. Thank you for your channel. Your narrative voice reflects confidence while explaining the topic in language that's easy to understand.
I was one of the evacuees, I packed a few essentials and headed east to grass valley for higher ground. It was bizarre to think you might not see your home and possessions again. Great video.
I moved from Yuba city to Pennsylvania temporarily and this happened while I was gone. My friends had to evacuate but luckily Yuba City wasn’t flooded. I moved back the year after it happened
Glad your ok. How do the ppl that live in the shadow of this inferior structure feel about it and it's builders ? And no it wasn't only because of heavy rain season . That kind of crap work will show pretty quick
@@scottygdaman Oroville residents aren’t the intellectuals that can be imagined. Meth heads will live anywhere, and some were/are in Oroville, and they don’t use condoms, and they don’t use masks, but they wear red hats of the Deplorable kind. They probably brag about the next damn breach and bet on it.
I left from Yuba city with my neighbors they helped up pay for rent when I was really young and extremely broke and ever since than for about 15 years I’ve done their yard work chores walked their dogs everything and then when we evacuated they let us sleep in their own cabin in grass valley they moved in with their daughter but we still go visit them extremely grateful for those kind people
@@nomorebushz excuse me, that red deplorable hat wearing meth head is my brother in law. Lay off him, will you?
I'd love to see a 2nd video showing how the renovation project fixed these issues.
Blancoliro. It's all there.
#1 Used sound engineering practices the second time around. #2 Enriched a lot of people.
quite agreed on this point
Just shooting from the hip here, but what do you bet the Damn was built by the lowest bidder?
@@kwilliamson1096 Considering it is the most important dam in California. Pretty fucking unlikely.
I've lived in oroville my whole life, the day the mandatory evacuation took place is a day I'd never forget. The news literally told us the emergency spill way will fail and we have to leave now. The drive out of oroville was like a scene from a movie. Insanity. Thank God it never failed completely.
Yep same and during like the days it was happening I had a bloody nose nonstop threw it all scariest and worst days ever 🙃
I live down river near Yuba City. If the earthen dam broke because of an earthquake or sprung a leak- how much would the Feather River overflow it’s banks? In other words, how deep would the water be in the valley? the
I was visiting in 1975 and experienced the earthquake. I now understand the dam was behind that.
Thank you for explaining so clearly. I knew about the failure of the spillway, but not why it failed.
Loving these new videos Grady
Noice
After listening to infrastructures, looking forward to yours dude.. More power!
Same
Super interesting to this ME. If I had known CE could be so interesting, maybe I would have changed majors. :-D
Hey man I love your videos....can you plz make a video on how to gather information, animations and how you edit your videos
I’m a Northern California resident and a first responder who had to mobilize for this... this is a great explanation of what happened! I would love to see a follow up about what they’re doing to repair the damage...
To repair it they will divert all dam maintenance funds to free health insurance to people who are unwilling to work.
@buffalo wt he’s not wrong
The part missing is that Brown was told about the maintenance needed to be done but choose to build a train to nowhere instead.
@buffalo wt its how they stopped forest fires...
it is long ago finished, using roller compacted concrete after removing ALL the unstable soil... you know, like should have been done in the first place. cali is a joke! what a fustercluck!
Wow, what a predicament for the operating engineers. Even though I’m a San Franciscan, the new coverage at the time didn’t give a clear idea of what was happening, it just focused on the disastrous possibilities. Thanks for your excellent, clear description of what happened.
Of all the risk and damage, the people who benefit from the dam only complained about a minor interruption in service. Those of us living in and around Oroville lived this.
My dad and Grandpa helped build Oroville Dam and my Grandpa was actually foreman over the Spillway project. I can tell you that they did not keep up with regular maintenance despite being warned that the spillway needed repairs.
People started to lose understanding of the importance of maintenance. Maybe related to how we more and more just throw things away, rather than taking proper care and doing repairs. Then the same people vote for politics who only care about making more things and ignoring upkeep... Mind, it's not a USA problem. It seems to be something that happens rather naturally as more and more power goes to governments and corporations, with the disconnect between management, consumer and producer. There will always be the guy that says "but see, it's still working _fine_ !" while the engineers are screaming, and then five years later (if it's even the same guy after all that time :D) blames the engineers for not telling him how bad the problem is getting :)
@@LuaanTi You say that like accidents caused by negligence are a new thing. I'm pretty sure they go back to Og the Caveman and his invention of the hut.
@@stormisuedonym4599 Yeah, that's definitely not intended. But the scale of the problem is growing, and it's surprisingly hard to explain to people why it's even a problem in the first place :)
@@karlhille9649 It's funny how it isn't just capitalist cultures that have issues with poor construction and neglect. Almost like your hypothesis is founded more in ideology than fact.
@@stormisuedonym4599 human nature?
The satellite pics of the dam are incredible. Puts things into scale.
What did it for me are the pictures of people standing on the spillways.
@Kelvin Higgs that's hardly the point here.
@@silentdrew7636 not really, as satellites are fake.
@@willblack8575 XDDDDDDD
@@willblack8575 I'm pretty sure photos don't exist either.
This is amazingly good. I'm not used to engineers talking in such a clear and engaging fashion. I always wondered what made that spillway fail, and now I feel I have a near professional level of understanding of what went wrong. This video is a perfect combination of formal engineering and practical example.
Yea this is great. I have family in Oroville. I really appreciate this video
Thank you for explaining this so clearly to a non-technical person! And we need on so many subjects responsible engineers, operators and regulators.
This would be the perfect recruiting tool to get high schoolers interested in Engineering. You hit the science and the human-side of what engineers do and who they impact in their practice! Great lessons here!
Great observation, there.
I agree with you, this would be great to get people interested in Dam's and Infrastructure.
I didnt go into stem because I suck at math. Not because its not interesting haha
The more you get a bunch of so-called experts involved in a project, the worse it is and this damn is a darned good example of it.
8th grade and this is very interesting.
As a lay person who, prior to this, knew nothing of this dam or its failure, I found this really engaging. You have a great way of describing engineering concepts just to the right level where it's interesting but I don't get lost! Thank you - really appreciating your work.
Same. Well done, Grady!
Coming from the newest video about this topic and also being a new subscriber, it is impressive how better technically you explain things now in particular when talking in the studio. Good job Grady
I remember how terrifying that situation was. It was barely getting covered on local news because i was living outside of California, but a big enough emergemcy that we got occassional updates. It was harrowing watching the spillways erode day after day. 🖤💜💙💚💙💜🖤 Thank goodness for all the engineers and technicians who worked tirelessly to mitigate damage during those long weeks. Great video, its fascinating learning about the small design adjustments which could have prevented such a failure. Your videos are wonderful! Much love!!
Dad was one of the engineers that designed the powerhouse there. He always told me not to live on low ground downstream of any dam.
That insight is…troubling.
@@JoeOvercoat don't believe him. Also, well duh. Living downstream of a dam means you place your trust in those who designed the dam and much more so in whoever is maintaining it
@@Lardum Exactly, California "progressive" politicians are more interested in pushing Marxist agendas which usually doesn't include their dam maintenance.
@@jonpark6650 true, if there's anything Marxists hate, it's dam maintenance. you're very smart.
@@gena1384 Give me all your dam questions from now on.
I can't blame them for using the emergency spillway. This was exactly the situation that it was supposed to be designed for. I am sure they were shocked as anyone that rather than working as intended, it instead proved to be a major weakness. The only bright side is that the weakness was revealed and now it can be fixed so it can actually be used if there is another emergency. The worst situation would have been if the main flood gate was close to imminent failure and then there was no choice but to use the emergency spillway, at which point it could have eroded out and caused collapse.
Cause they were stupid. And lazy. Lunch time!!! Look at the soil at the emergency spillway. You can't tell me they couldn't dig a number of test holes and find it was more soil than bedrock. A friend had to evacuate with her daughter. The traffic jams were unbelievable.
@@scottslotterbeck3796 exactly. This dam should’ve been run privately by a company that had its own money on the line. If that were the case, they would’ve never dealt with this.
@@thatcarguydom266 That sounds lovely in theory. In reality, when a private company makes a critical error or it comes time to clean up (such as former mines) the company can and does declare bankruptcy and the public is left footing the bill. Invariably, the public inherits the risk of large projects.
@@thatcarguydom266 Yeah, having a company with money on the line always works. *Looks at Fukushima*
@@Ealsante Exxon, and so on and so on.
I worked as a Carpenter to help repair the spillway, etc for nearly 2 years......good to see this post.
This guy never disappoints. Great and informative video
I remember the night of this crisis. I was hanging on every news update trying to follow in realtime, but those bits and pieces never gave me a full picture of the story. Good video.
probably the most vivid memory i have of evacuating from this is finally getting to a town outside the flood zone, finding a mcdonalds, and doing so much stress eating.
Oh I member was there also for me it was me in chico at the Dennys with like 8 of my buddy's after that then got the joy of the paradise fire after that gotta love norcal
The California dream. The dam incident is the only disaster that made me glad to live in Kelly Ridge. With the fires we have had to evacuate at least once every year.
Ouch! I was in Williams, at the McDonald's there. Far enough away, but still we wondered. California is great though, imo, dam failure like that hasn't happened in however long. I do feel awful for forest fire victims.
Glad it all went okay, leaving home last ditch is never fun.. Hope the house was intact. How are your family doing nowadays after that
@@jonney_boy Yeah I went to chico and had to stay at my Grandma's
Really interesting video. I do wonder however about the conclusion that with hindsight most people wouldn't have utilised the emergency spillway. The conclusion that they didn't need to seems accurate, but they also had the ability to return to the primary spillway if there were any issues with the emergency spillway; in the end utilising the emergency spillway uncovered a large risk but one they could safely mitigate in this case (by returning to the primary spillway) and had the unintended consequence of demonstrating that the emergency spillway couldn't be relied on in its current state. It also meant that they knew of the issues with both spillways at a point where both could be used. extending time to evacuate. If they had continued to operate the primary spillway and damage reached a point where complete failure was a risk, then moved to the emergency spillway then they'd have considerably less time to respond to the risk of the emergency spillway failing. In short, I think both scenarios allow for both spillways to be run until near failure, but running the emergency one earlier gave them more time to respond to the potential failure of the dam.
Fantastic video of an extremely compelling, potentially deadly disaster! I lived thru the event & was glued to multiple news channels & gov't websites. It could've been so much worse! CA considers itself a little ahead of its peers when it comes to community safety standards. This made the failure all the more alarming. But what I liked most of your video was the very calm, consistent & steady presentation, communicating complex engineering concepts, but breaking them down into concise, easy-to-follow explanations. By bringing it all together & explaining how what happened combined w/ design flaws, plus the extraordinary record 2017 rainfall resulted in the disastrous consequences that followed. You tied it all together: what went wrong, why/how it happened, what could have been done better, & then examined corrective actions to prevent possible recurrence. As I am a non-engineer, you did an excellent job educating the viewers like me, w/out being overly pedantic or off-putting. Great job! Looking forward to your additional projects! You're like the Dr. Lucy Jones, renowned So Sal seismologist explaining the complex facets of our regional earthquakes. But w/ dams!
Yes I'd love a video about the repairs!
I think it would have to be a multi-part series.
Really curious if they actually flew in rocks on helicopter to stabilize terrain or of that's was just PR / a one-off stunt!
@@snigwithasword1284 I don't believe they'll carry all of the embankment rocks to the site with helicopters, in case maintanining a service way for trucks to carry the rocks would be more economical than flying these rocks.
@@snigwithasword1284 we had something similar happen in the UK in 2019. The military used helicopters to dump loads of bags of sand on the failed area to stop a collapse of the dam wall. Have a search on KZhead for "Whaley Bridge Dam" and you will see plenty of videos and news coverage. Thankfully they managed to drain the dam and avoid a collapse.
@@enescankayhan8999 He's refering to the tweet by @CA_DWR where they said that they might use helicopters to fly in rocks during the emergency itself. twitter.com/ca_dwr/status/830972294784655361?lang=en
I love videos discussing disasters (or near miss) and what exactly lead up to them. It's almost always a pile of relatively small errors that accumulate to disaster. Understanding how each of those was allowed to persist, and what changes are necessary to avoid similar situations in the futures, are lessons we should all be more interested in.
Remember they missed Mars by .00000000000001mm
Mandatory inspections are toothless if you can't compel them to actually fix the problems they find! That's a running theme on Well There's Your Problem, go listen to them!
In this case, mischaracterizing the underlying soil is not a small error. It is criminal negligence. I am quite certain that the guys actually building the primary spillway knew that it was only a matter time before it failed. Someone higher up made the decision that not going over budget was more important than the safety of downstream residents.
go listen to "Well There's Your Problem" Podcast (the Vajont Dam episode is a doosy)
Fantastic summary of this failure. I especially like how you take a bunch of complex factors and simplify them so that the average layperson can understand.
This is one of those random video recommendations that I'm really glad I clicked. Fascinating, scary stuff. The shortcuts, bad decisions, and inspection oversights are just.... there's no excuse.
On the other hand, by using the emergency spillway, they discovered how broken it was, too.
Yes, and thankfully, they made good decisions to mitigate that unexpected failure.
@@trafficsignalman Yep, it sounds like the operators here did a fantastic job in spite of the serious and repeated failures of the engineers and regulators. My degree is in engineering (not civil) and I've worked as an operator at a natural gas plant. It's extremely difficult to make the right choice under mounting pressure (both literal and figurative) so I give a great deal of credit to those individuals.
@@somedumbozzie1539 The operators aren't responsible for those costs, the company that owns the dam is. The operators aren't responsible for the decision not to make the repair. Assuming the story you're telling is even true, that's the definition of "luck not talent" because the sheriff doesn't know anything about operating a dam or its spillway.
Exactly. This shouldn't have happened in the first place, but at least it's one hell of a warning shot. Aka next time shit should be prepared way better, the keyword is: should. I personally wouldn't bet my life on it.
@@somedumbozzie1539 What was called for wasn't a small repair but a major rebuild of the entire spillway system. The primary spillway needed to be entirely rebuilt from the foundation up with proper features for the condition of the material under it, and the emergency spillway needed a complete redesign due to the highly erodible country rock.
I really love when you cover particular case studies like this with all the relevant models, analogies and the actual science and engineering. Really puts the things I'm learning on my degree into better perspective :)
I'll never forget my Strength of Materials class. The prof drew up the problem and gave us (sophomores) 20 minutes to solve it. We all said, "yeah, it'll shear" And he told us that he drew up the Hyatt Regency walkway failure in Kansas City. Amazing what happens when people on the jobsite make snap decisions.
As someone thats NOT an engineer, I find these vids absolutely fascinating!
I am a musician, but two of my brothers were engineers, one civil and one a mining engineer. I've always been fascinated by the topic and really enjoyed with brilliant video that explained so much and so well for folks like me that have no expertise to speak of, but are really curious and amazed by engineers and what they do . Thanks.
“...15% the speed of light reaching the moon in about 9 seconds”. I was impressed I rewound the tape to listen to it again
Are you watching this on VHS?
@@VeraTR909 Lol your comment has me wanting a youtube mod that simulates the "kerchunk-whirrr" classic VHS rewind!
@@chucklebutt4470 Yep. And you can't watch the next video until you've rewound the previous one.
Ha! Me too.
@@chucklebutt4470 Haha that would be a great april fools joke, removing the ability to skip in the timeline and instead giving you 'fast-forward' and 'rewind' buttons ;P
<a href="#" class="seekto" data-time="813">13:33</a> Grady: "Instead of trenching them into the foundations below the slabs, they reduced the thickness of the concrete to make room for the drains." Me, who just learned how stagnation pressure can create an additional uplift force when acting on the underside of a submerged object less than 45 seconds ago: "OH NO THEY DID NOT"
If you have ever farmed in rocky soil you would understand that rocks float on dirt.
Did you know.. they built an actual station that floats... underwater... like trains coming into that station... the whole thing is secured by the equivalent of guy ropes My point is.. they are keeping a floating station stable with heavy trains rumbling in every 30 seconds.. surely they can fix a cot damn DAM! Reference; barangaroo project
@@tonysuda9066 Your comment immediately prompts: How is an underwater floating station useful? If you get off at that station.... then where do you go?
@@Graham_Wideman dude its awesome the station is coccooned and the entry is from the sea bed and the exit goes into the city network.. mind fk i know
@@tonysuda9066 can't find it, the website just has a bunch of other stuff but if it's connected to anything with a rigid structure, which would be necessary for people to get in and out, then it isn't really floating.
Great content. I've always been fascinated by the movement of water and man's efforts to control it as well as the damage it's capable of and how it can change a landscape. I've watched several of your videos now and will be watching more when I have time. They are very informative and you are very thorough. I appreciate that. Cheers.
Beautifully written and delivered. As an amateur mason and engineering buff, I found it fascinating. Thank you.
Welcome to Oroville! Where were you when it was failing!? We could have used your help explaining the situation as it unfolded. Plus the rebuild- The greatest engineering feat in Decades! ;-) Thanks for posting! Juan.
Thanks Juan. Your channel is all over this comment section. I went and checked some of your reporting during and after the crisis at the recommendation of your fans and it is excellent.
@@PracticalEngineeringChannel Thanks Grady!
In my home in Olivehurst, went all the way to San Francisco during the evacuation.
Good to see you here Juan. I was one of the boat operators in the thermalito diversion pool. I watched your updates daily when I was on that job.
Here's Juan's playlist for this event (79 videos): kzhead.info/sun/is2kmdJqi3xtlWg/bejne.html.
The olympic swimming pool vol/2 sec to garden hose flow at .15c is the kind of thing that had me subscribe. 😁
It's mainly everything else he talks about that makes me subscribe. I do appreciate that fun bit though
you are not thinking big enough, the moon-shot calculation should have been: with you holding that hose, how long does it take to reach the moon.
I have had a drink out of a garden hose and opened the hose end a bit too fast, I can certainly tell you it felt like water approaching C.
Garden hose going .15c, sounds alot like the day after no nut November
Restating his calculation with different notation earned you a like.
Good stuff as always. You do a great job explaining sometimes complicated subjects in a very understandable way.
The info. here is phenomenal! I live in Oroville and did when the near disaster hit us. I live in downtown Oroville, three blocks from the river, so if the dam would have broke we would have been wiped out in seconds. I appreciate very much all the work you put into this video. You did a great job of giving us the info. needed, wanted and done in a way we all could understand it as well. :)
The Blancolirio channel has excellent videos of this project while it was under construction. Easy to understand interviews and conference calls with the officials, engineers, construction teams and environmental folks. I myself enjoyed the fly over updates and the actual project cost numbers.
I watched the entire history of the crisis through his channel here on KZhead. Real time reports on the dam issues and dealing with rumors and incorrect information were being reported by Juan during the entire event. And then following the repair process. He did an incredible job explaining how the issues connected to each other.
Was lookin for this
Damn, $1.1B to repair. That's about 4x what I was expecting.
He has done some of the most competent reporting I have run across.
I'm on the other side of the country but followed along in real time thanks to Juan's reporting. We need more competent, independent, objective journalism like Blancolirio and Grady produce. Excellent and informative content.
It's interesting that the Engineers built the Emergency Spillway for use in case of an Emergency. But when the Emergency came, they were hesitant to use it.
"Emergency" isn't an on off thing; there's many levels of emergencies. In any case, my guess would be that they realized that the same thing that weakened the service spillway (and caused very obvious erosion on the supposedly "solid bedrock") would make the emergency spillway even more vulnerable. Emergency solutions are risky even when things work _mostly_ as designed; if unexpected things start happening...
@@LuaanTi See 3 mile Island for more details.
I can understand this, for two reasons--One, it's a "last resort", and no one wants to use their last option, because if it fails, you have nothing left; and Two, they probably realized that the same geological issue that undermined the main spillway applied to the emergency spillway as well.
They knew it would remove all the soil that should have been removed in the first place.
I lived 20 minutes from that dam when that all went down let's just say ca and dwr is bad with routine maintenance it almost seemed as if they were more worried about the gold that got washed out then they were worried about civilian safety they were by the truckload takeing the mud that got washed out of there to a private lot that had armed guards watching and patrolling it 24/7 and trying to prevent people with claimes along the feather River which is what that feeds into from mining the area immediately after that happened and for years after not allowing anyone near the dam to see the destruction
I like the way Grady explains the technical side of civil engineering. Great demonstrations and visual aids. I am new to this channel, but the content is awesome.
This is the 1st story I've watched on this channel. Very well done. Looking forward to many more. Thanks.
I'd absolutely love to see a follow up video on the repair and rebuilding of the spillways. Great video as always.
I’m not an engineer. Just like to learn. This was a really well done video. I feel like I’m ready to put on a hard hat, put my foot up on one of those rocks, and shake my head in dismay.
laughed so hard at this!
Wow😂😂😂😂😂😂😂😂
Thanks DooDoo Poop
I found this very informative and helped me understand the oroville issue. I just moved up here 6 months ago from Monterey. I love the beauty in the area but still miss the ocean. I appreciate what you presented. I am sure the engineers learned a big lesson as we are human and make mistakes. especially by those that didn't know the real trust back in 1968. Live and Learn is all we can do.
I am currently working my way slowly into environmental impact evaluations and as a non-engineer your videos are a very useful tool for an educated non-engineer to get an understanding of some of the questions I need to ask, the issues that we need to confirm etc.
Honestly, it sounds like they actually made the best choices given their situation. By alternating what areas took damage, it prevented either from taking such a critical failure that the problem became unrecoverable. Still a bad situation, but could have ended a lot worse if they had let all the damage to to either the emergency spillway or the chute.
I agree. I think he's entirely incorrect. They engaged the emergency spillway with a chance of success and the ability to reverse course if it went poorly (which it did). Not using a designed feature for its intended use would have been unforgivable had the alternative ended up being worse. If one studies Fukushima, they'll see that many opportunities presented themselves to take a "lesser of two evils" approach and, in every case, they stayed the present course, instead. The outcome ended up being far worse than it needed to be.
I think the real mistakes were in building and planning. The engineers may have handled the emergency in the best way, but mistakes were made and at least some seemed avoidable.
It was also a chance to test the emergency spillway..........if not for their choice, they may have found out at a later event that the emergency spillway was also not up to par. At least in this event, the dam did not give way. It would be a shame if at a later date the emergency spillway somehow became an even bigger problem. Also, they already had the river and hillside to repair, so the damage was wrapped up into one major event.
@@CGT80 I think the bigger issue is that they should’ve tested everything when it wasn’t needing to be used. Governments (or in this case the California agency that controls the dam) always go for the lowest bidder, however, and the citizens of nearby communities nearly paid dearly for it. Look no further than Chernobyl to see why you ALWAYS test before putting into use
@Dethyl my point isn’t that the lowest bidder never has a good plan or idea, it’s that they’re often selected REGARDLESS of the quality of the idea because it’s “what the government can afford” because they have to pay themselves 200 grand a year. It’s corruption, and California is Rife with it. Look no further than the US F15 Lightning II program. It started out as the cheapest option, a budget F22 with VTOL capabilities, but now, it’s budget and costs have ballooned out of control because of issues in the design and screening process of both the plane and its blueprints when being selected. The F22 was expensive, but proven. It’s for this reason that I believe that A: when applicable, allow the people using the equipment to survey and approve plans, blueprints, or contracts with contractors, be it military, industrial, etc. B: whenever possible, if it CAN be run privately, then it should be run privately. When someone’s fortune is on the line, especially one that isn’t constantly replenished with taxpayer dollars, people tend to get their act together, or the veil otherwise gets ripped away and they get boycotted, removed, punished, etc. The private industry will, with few exceptions and some small amount of regulation, always be more effective, as well as efficient in using their resources. The government and its agencies have no direct repercussions for running over budget, out of money, or causing a disaster, short of being voted out, but in that case they still get a pension (which in my opinion is utterly foolish. They should’ve saved for retirement if they don’t plan on working). A private corporation on the other hand is constantly trying to get that balancing act for efficiency and effectiveness, and if they fail, the market will usually punish them with bankruptcy or some other form. The business is inherently efficient, the government is inherently wasteful.
I have heard this case study several times from dam safety experts and you put them to shame. Just earned a subscriber from a dam safety inspector.
First time I've watched one of the videos on this channel and it was excellently done. The production quality was impressive. The video footage used during the explanations was stellar and the explanations were technical enough but explained clearly in terms anyone could understand.
Please do cover the rebuild; I think it would be most interesting!
@Blancolirio did a whole series about it.
Be aware the Blancolirio route is a deep rabbit hole, three playlists with 112 videos kzhead.infoplaylists
You seem to have missed a very important part in the oroville dam crisis. They were warned over a decade ago about many of these problems. The lack of repair work contributed probably more heavily to it than the original failures did. I remember reading an article about it in the local paper when I was in highschool. It would be nice also to see a follow up video on this topic about how the repairs are going. As a local I have not been hearing good things.
warned a decade ago... hmm... Beirut explosion next?
The Inept Government diverted millions of dollars to Social Programs rather than maintaining the dam. (I lived most of my life in California and watched the incompetent government. I couldn't take it any more and moved out of California.)
@@keitha.9788 About a week after the spillway failure (IIRC) Governor Brown ok'd a bill giving several millions of dollars to Legal Aid firms to assist illegal aliens from deportation. How much of that should've gone to repairing our crumbling infrastructure?
It was cheaper to do nothing. Fuck the people, those that live might get some money, eventually. Risking people's lives isn't punishable.
@@keitha.9788 Needs more regulation.
Excellent recap supplying enough information for many of us to understand what transpired and how to rectify the problem in both the repair and future construction. Very much appreciated.
Excellent video. I followed this closely as it happened. I gave my family daily updates, but this video explains it much better. I think the repair was done beautifully, and those engineers deserve high praise. Again, great video guys! JW from K.C.
I appreciate that you explicitly called out the important fact that trust was broken, and also gave specific, supporting examples of this, throughout the video. We all rely on competent professional observers to do just that, in every field of study! Thank you! I also appreciate that you did not hyperbolize or dramatize it. You struck a really good balance, here!
agree well said
SNAFU/FUBAR: In all humans institutions, these are the governing principles.
Kind of makes me think of 2 weeks to slow the spread... Experts.
Your approach shouldn't rely on "trust" or other human competencies. I suspect the lack of an adversarial quality system is the root cause. People responsible for reviewing/certifying the original design and the ongoing inspections did not have sufficient organizational clout and power relative to those pushing the status quo.
@@frednicholson An adversarial certification process? That's a really good idea! It would nicely mirror our legal system, which (presumably) represents our collective best effort to reliably get to the truth. "Unsafe until proven otherwise!" 😂 Regarding trust, I wasn't talking about the certification process. I was talking about the _political_ process for normal citizens to decide whether they should invest energy in changing things, now that it has happened. Trust (or 5+ years of study) would be necessary for a normal citizen to become sufficiently educated to make an informed decision about whether they are satisfied with any given solution that a politician offers to what happened, there.
It is an amazingly large responsibility that engineers and inspectors have to be the person to say "This is not acceptable" when it means that a project may go over budget, run late or have to be corrected. It certainly puts them in a unenviable position to decide that millions of dollars have to be spent because of a situation that might never happen.
If this is the system then it is wrong. Engineers and inspectors should report any worries without any possibility for a consequence related to their job. They only have to care that the worry was documented, and no one can say that they were silent.
When you hear about the pay you get as an engineer, you also need to hear about the responsibility that comes with it. If you don't do your job properly, people may die. Your highest concern should be the quality of the job you're doing, not how much your bosses might dislike delays and budget increases.
@@Mike_lis In an ideal utopian world I agree with you. In the real world it is at times delusional. Of course it should not be - but it is. You could get fired - you could get an undeserved reputation and be unemployable in your area - and nothing would change. So ignore it? Hell NO. But sometimes it is better to be inside the tent p issing out that outside the tent p issing in. There are many ways to skin a cat.
At my job we call it telling the program that “their baby is ugly”. No one like doing it nor does anyone like hearing it. I’m a flight test engineer for the USN/USMC and when we tell them their baby is ugly it means it’s not safe. Dirty job but someone has to do it.
Its a frustrating fine line to deal with as an engineer. I have had plenty of projects that are not completely essential, but still important get shelved at the 60% or 90% design phase because it wont fit the budget of the agency. They arent things that would result in a catastrophic loss of life, but if massive storm events could easily lead to a neighborhood getting flooded out. I understand that the budget is the budget, but I also always go back to the line of "no one complains that their city isnt flooded enough"
Outstanding presentation of the entire event. Practical, interesting and informative.
Thanks for the video! I live in Marysville not too far from Oroville Dam ...No trust here ! I was evacuated in 2017 it was terrifying !
One of the worst mistakes they made was running the power cables through the emergency spillway and controlled spillway areas at all. They should have been routed around the other side of the river wash area in front of the dam.
That was knuckle head engineering
That would prove they knew it could fail, so they put it downstream. All engineers of dams should be required to live downstream of it and not allowed to evac.
@@denniscross7142 hmmm, there's a problem, let's put innocent engineers in danger instead of the people incharge who didnt order the hills to be checked.
@@cookiecraze1310 that would be the engineers then
@@jonnie2bad you‘re forgetting the people who set the budget, effectively limiting the engineers in what they can do.
I love how Grady describes complex issues...he does such a good job that he makes complicated issues understandable by us non-engineers! (who would have thunk that a channel about issues in civil engineering would be one of my favorite channels on KZhead!)
Retired British Mech Eng here. Great post, thanks.
That dude just said a consequential chain of tribulations and it gave me an eargasm…
Your passion for civil engineering is so contagious. I never would have thought such a dry subject matter could have so much life and inspiration breathed into it! Keep on being amazing!
Please make a follow up on the repairs! I live nearby and went to see the repairs in progress a few times. The damage was staggering, but the repairs are a scale of construction I had never seen before. As a non-engineer, I would love a video helping me understand what I saw.
On the reliable and comprehensive Blancolirio channel, operated by Juan Browne, try digging into these two playlists which cover the Oroville crisis and repair project: Oroville Spillway Failure Series Feb 2017 [79 videos] kzhead.info/channel/PL6SYmp3qb3uMCqXIp7mYmiAPeEVoazpUE.html Oroville Spillway Phase II [29 videos] kzhead.info/channel/PL6SYmp3qb3uP2yh1sveH6AKazCUq2sDQn.html
@@jonbus766 please stop posting these stupid links. Im getting tired of reporting them sa spam
You have supplied even more good info than I usually get from Juan Browne. Thank you
An excellent synopsis of what things led to the spillway failure. A good lesson for future designs.
If I could only say one sentence to describe the most problems possible today, it would be this. The people running things are far too insulated from the people doing things
Except that this was built 50 years ago.
@@Cheepchipsable one of my bridges went in service in 1884. It still has cattle guards for cattle drives. I have several others that are early 1900s.
@@Cheepchipsable when it was built has nothing to so with the statement, the people doing things where telling the state the spillway needed repairs for years and the state kept saying no the costs don't justify the risk. The state was then sued to repair the damn and again failed to do so before this happened. So the original statement of the people running things vs people doing things stands correct
Exactly!!!!! Dead on balls accurate, Henry.
@@Cheepchipsable I’m 38. 50 years ago is only 12 years away. It’s not that far removed.
Is that Wintergatan playing in the background? Respect!
Yup. It's listed in the video description.
It is! It says so in the description.
time stamp? I must have missed it
@@georgobergfell It probably starts a bit earlier but is pretty quiet and becomes noticeable around 15:00. More noticeable around 15:40
@@alpsoysal3586 thx, it's barely noticable
Excellent information and video. I live at Canyon Lake Texas. I've lived here for only 8 years. About 5 years before I moved here, the dam at Canyon Lake that controls the Guadeloupe River was filled beyond the maximum level. Massive storms filled the lake beyond the normal maximum level, and the water flowed over the spillway built for this exact event. The flow was so strong over the emergency spillway that the solid rock was broken away in huge boulders and exposed stuff that had been on the bottom of the ocean millions of years ago. Down stream, there were campgrounds built along the river for motorhomes and cabins for rental. Most of them were washed away. Now they sell tours to visitors to hike in the gorge that was carved out by the water.
YES! I'd very much like to see a continuation of this video covering the repair works!
At <a href="#" class="seekto" data-time="520">8:40</a> "This hillside was assumed to be solid, competent bedrock." Good grief. That hillside should have been examined, drilled and tested by professional geologists.
Hi merry, I have a construction company and I’m building an 800’ dam and was wondering if I can hire you for consult on major decisions
@@eleeleelee7513 good choice, he seems like a really well versed expert on the topic
Captain Hindsight
@@eleeleelee7513 well if you build a multi billion dollar dam there should be at least the budget to make analysis at the regular chute, wich also didnt happen
Idiots the pracical engineer calls "Most competent Engineers in the industry " did.... and said everything was just fine. And NOBODY is held accountable. While this clown makes propaganda calling them "Most Competent"
My mother lives downstream from oriville. She was evacuated and that was a worrying time for our family. Thanks for the great explanation as always!
ok
@@kodo1232 alright
Watched this video because I became aware of it when it was shown to me for the first time by relatives we visited yesterday in Oroville. Wow! Now, all of the things I saw made sense and the repairs done to mitigate future risks. Thanks for the excellent presentation. A+++
This channel is freaking amazing. I never hear anyone discuss literal practical engineering this way, a way that takes modern applied science and methods and makes it understandable. With modern and historical analysis even. It also sickens me that this wasnt a bigger national story, which shows where journalism outlets are. Its just my view, but it would seem to me that he makes another terrifying point: when the safety of bureaucrat careers is prioritized over the science known to the engineering community itself, your civiliization is in serious danger and it may not be obvious until it is too late for the citizens who will suffer the first and hardest. Thank you for these videos. I'll probably binge watch this channel for a bit. It teaches so much. It feels like it should not be arcane knowledge, but is. Rare channels like this make one feel their secondary education was quite a cheat.
"Consequential chain of tribulations" is my new band name.
stop drop and roll that solves every problem lol
Where are you playing? Id come and see a band with that name!
I liked you better in Scarecrow Boat
How about "Satanic Spillway Of Demonic Resurrection Breaking Open Gates Of Hell" for Deathmetal album name?
@@UsoundsGermany I have this image of a ticked-off Satan yelling at souls--"I had those gates installed for a REASON, people! Only I decide if they're to be thrown open!"
"not good stuff - aka weathered rock and soil" Thank you so much grady for explaining these highly technical terms, i'd be lost without you ❤
The Sierras are relatively young, as mountains go. The power station for Oroville Dam was carved out of solid granite. Now, the Coast Range, that's some old, crumbly rock...
We call it "not good stuff" in dirt work as well. If it doesn't compact good, pumps when its just barely wet, etc its "bad dirt" "sh*t dirt" "not good stuff" lol
@@beardedzeus1337 TFW your dirt ain't worth dirt
Very interesting video and very informative, I appreciate you taking the time to explain all of this. I was at work when the evacuation order went out and could not get home so ended up evacuating with only the clothes I was wearing at the time. That was a very scary day and not one I'll soon forget.
Can't believe that after years of watching these videos the "how's that for flow rate equivalency" joke is what made me make sure I was subscribed lol
As a geologist with more than 40 years of experience (in at least 10 countries around the world) I just had to look at the regional geology to know that money AND Engineering Egos played a critical role in the poor investigation and the non-implementation of preventative measures for the specific geological environment. In the specific instance just 1 cored rock borehole would have been sufficient to alert the engineers to the dangers that could be expected. Congratulations on an excellent presentation 👏
I had to wonder what would have caused the first issue of not knowing the ground they were building on. The second issue of inspections and mitigation of issues found during them is a complete CF of epic proportions. Having been a fire alarm technician that attempted to do professional level work as an inspector and technician, the issues that craptastic local fire marshals missed during their checkouts of fire alarm systems is just brilliant. These firefighters need a year under someone that knows this end of their job as fire marshal to show them what the hell they need to watch for here. (Electrical system knowledge versus firefighting knowledge.)
No one thanks the engineer who spends $20K-$50K more to produce a geotech report to inform a design to prevent a failure that would otherwise not happen.
It was a crazy time. I live 30 mins away and work in Oroville. We had to evacuate to areas like Chico.
I remember this as well. I live about 40 minutes south of Oroville. The roads were so backed up with evacuees, if the dam HAD given way, there would've been nowhere for those people to go.
@@jujubee463 I'm downstream myself, near Yuba City, and we were evacuated at around 7 PM. Even the backroads were packed; we ended up going through Colusa and up to Chico.