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Realtime Analysis of the Oroville Dam Disaster
- alextheparrot 10y agoI really enjoy the graphs and analysis produced by this project, but does it irk anyone else that the Y-axis does not start at 0 in all the graphs? There are some graphs further down the page that start and 0 and they seem to show the data so much better (Water is increasing, but not 50x or whatever).
- harlanlewis 10y agoThis is terrific. Would be a great resource for journalists to identify and understand some of the key points that can then be shared in a more public-friendly format. I wish all stories had this kind of accessible data “behind the news” that could be explored! Here's a great article on climate change's effects on our water infrastructure in light of the Oroville Dam's situation: https://www.nytimes.com/2017/02/14/opinion/what-californias-dam-crisis-says-about-the-changing-climate.html https://www.nytimes.com/2017/02/14/opinion/what-californias-... An example - the bulk of California's water storage is in the natural reservoir of mountain snowpack. The large volume of precipitation this year, much of it as high-altitude rain falling on snow, has caused an extraordinary amount of snowmelt in a short period of time. The natural reservoir of snowpack is rapidly released into our manmade resorvoirs and strains or exceeds their capacity. This cycle of alternating extremes, drought to wet, is expected to continue, and our water infrastructure's capabilities must be planned in light of that.
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- caseyf7 10y agoThis is a great analysis. However, this seems a little off: "Based off of our estimate, for every inch of rainfall at the Oroville dam, 136,790.5 acre-feet will be added to the reservoir." The relationship probably isn't linear. Much less of the first inch of rain makes it to the reservoir vs. the 5th inch of rain. Hopefully, the next iteration will project how many inches of rain it will take this weekend to top the spillway again.
- AnimalMuppet 10y ago> Much less of the first inch of rain makes it to the reservoir vs. the 5th inch of rain. Depends on whether the ground is already saturated.
- pilom 10y agoEven if the ground is saturated, plants still will absorb more of the first inch than the 5th.
- AnimalMuppet 10y agoI don't think that's right. If the ground is saturated, the plants won't absorb any of it, because it won't sink into the ground at all, because the ground is saturated. (That is, unless you're talking about plants absorbing water from their leaves directly, before the water hits the ground. I don't know that plants do that when their roots already have plenty of water, but I also don't know that they don't.)
- acomjean 10y agoThey have models for run off. In my previous career we used tr55 analysis of watersheds, this included surface types, slopes and areas. You model for various storms once the model is built. We didn't have to deal with mountain snow packs which add another factor. Edit: I think newer programs to model exist now. Some are here https://www.nrcs.usda.gov/wps/portal/nrcs/detailfull/national/water/manage/hydrology/?cid=stelprdb1042480 https://www.nrcs.usda.gov/wps/portal/nrcs/detailfull/nationa... 165 page PDF describes it. https://www.hydrocad.net/pdf/TR-55%20Manual.pdf https://www.hydrocad.net/pdf/TR-55%20Manual.pdf
- karlkatzke 10y agoIt is quite a bit off. The Upper Butte Creek Watershed, which is the watershed that drains into Lake Oroville, is 3200 square miles. Much of this watershed is mountainous. The amount of water that will flow into Lake Oroville is heavily dependent on temperature (what forms snow vs. what melts snow), the existing snowpack, the ground saturation state, and precisely where in that 3200 square miles the rain falls.
- stuckagain 10y agoWow almost every statement here is wrong. #1: the dam is managed in the winter about 1 million acre feet below the top, for flood control purposes. The spillway has been operating all winter long. #2: The operator cannot decide to use the emergency spillway. Water just goes over it when it approaches the top of the dam. #3: no water has gone over the dam. That would destroy it.
- crisdux 10y agoRegarding #2, they can choose to decrease flow out of the main spillway and let it go over the emergency spill way - From my understanding, that is exactly what happened over the weekend. They were trying avoiding continued damage to the main spillway.
- maxerickson 10y agoQuoting from one of the LA Times updates linked from the link: The result is a balancing act — drain as much water as possible as quickly as possible while trying to minimize further damage to the spillway. The main spillway was returned to action, but at reduced capacity compared to what it could normally do under the current conditions. After all, the spillway needs to last for the remainder of the rainy season. The stated capacity of the main spillway is 250,000 cubic feet per second, once it became clear the emergency spillway was not holding up, they increased the main spillway to 100,000 cubic feet per second. So limiting damage to the main spillway is an ongoing concern.
- mintyfresh 10y agoThe capacity of the intact spillway is ~250,000 cfs - the capacity of the Feather River through Oroville and Yuba City below, currently in the lower flood stages with 100,000 cfs outflows from the main spillway, is much lower than that. In addition to attempting to minimize further erosion of the main spillway, they set an outflow level that wouldn't flood the towns downstream.
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- mturmon 10y agoKind of a fun study, enabled by the presence of so much public-domain data from CA DWR. One piece that's missing from this analysis is upstream precipitation. You are sensing precip at Oroville itself, but water in the dam comes from everywhere upstream (3600 square miles according to [1]). As well as (potentially) snowmelt. People doing forecasting of reservoir levels will be integrating distributed precipitation information, snowpack, and temperature, with a soil runoff and routing model to get predictions. [1]: http://cdec.water.ca.gov/cgi-progs/profile?s=ORO&type=dam http://cdec.water.ca.gov/cgi-progs/profile?s=ORO&type=dam
- stuckagain 10y agoIndeed. If we want to leave the analysis to professionals we would look at the CDEC river guidance for the Feather above the dam. Here it is. http://cdec.water.ca.gov/guidance_plots/MFP_gp.html http://cdec.water.ca.gov/guidance_plots/MFP_gp.html As you see the forecast flow is only about one third of that experienced on Friday past.
- mturmon 10y agoThanks for locating that. I work with people who do retrospective runoff and streamflow modeling (using past measurements to make better models), but not the predictive stuff in the graphs you linked.
- stuckagain 10y agoNOAA has nationwide river sensor and guidance data if you are interested in a river near you. https://water.weather.gov/ahps/forecasts.php https://water.weather.gov/ahps/forecasts.php
- seanp2k2 10y agoMore analysis on the dam situation: https://www.metabunk.org/oroville-dam-spillway-failure.t8381/ https://www.metabunk.org/oroville-dam-spillway-failure.t8381...
- xbryanx 10y agoThose are the most informative pictures of the situation I've seen yet.
- chris_7 10y agoIs welding giant metal sheets over the hole an option?
- karlkatzke 10y agoNo. You would need to anchor the metal plates to something, which means you'd need to drive spikes down into bedrock and then weld things to the spikes.
- mintyfresh 10y agoThis post [1] from that thread is the simplest presentation of the current and expected scenarios than anything I've seen elsewhere, including the OP. If they are able to run the main spillway at the current rate of 100,000 cfs without concern for further major erosion, the outflow outpaces anything but the highest inflows from the recent storms. [1] https://www.metabunk.org/oroville-dam-spillway-failure.t8381/page-11#post-200242 https://www.metabunk.org/oroville-dam-spillway-failure.t8381...
- kolbe 10y agoI like what you're trying to accomplish, but you are missing a very helpful piece of information in your analysis. I'm sure you noticed how poor of a predictor rain fall is in your assessment of how much water will be added to Lake Oroville. This is largely because Oroville is filled from Sierra Nevada runoff. If a particular storm system is warm (as was the case with the latest one), it will mostly rain in the Sierras. This has a twofold effect: one, the precipitation doesn't stay put at higher elevations (as snow does), and two, it melts the existing snow, causing it to also be added to the downstream water accumulation. So a key part of forecasting is not only to look at expected precipitation, but also the expected snow levels.
- lightedman 10y agoAnd the expected temperature of the falling precipitation, and a whole lot of other meteorological stuff which is involved, so in reality this dataset, while admirable for effort, is really useless as there are way, way, way too many unaccounted-for variables.
- sverige 10y agoIf I'm reading the data correctly, there is no snowpack above Lake Oroville right now, so it's all about rain at this point. https://www.wcc.nrcs.usda.gov/snow/ https://www.wcc.nrcs.usda.gov/snow/
- kolbe 10y agoI'm having trouble pulling that map up, but I believe there's snowpack at 5500' and above right now, and there's a huge amount of land upstream of Lake Oroville that is above 5500'. My data is this: here's an Instagram tagged at Emigrant Gap (5200') taken four days ago. https://www.instagram.com/p/BQYzN3sA76u/ https://www.instagram.com/p/BQYzN3sA76u/
- mturmon 10y agoOroville itself is at 900 feet altitude, but the Oroville watershed extends into the Sierra Nevadas, including alpine valleys at 5000 feet. The Sierras have record snowpack this year (150 inches in places, so I hear). Approximate watershed is seen in the map at: https://en.wikipedia.org/wiki/Feather_River https://en.wikipedia.org/wiki/Feather_River
- fptoperation 10y agoMore analysis on the dam situation: http://bit.do/meow-meow http://bit.do/meow-meow
- AnimalMuppet 10y agoPlease tell me Betteridge's Law of Headlines does not apply here...
- Stratoscope 10y agoDoes Betteridge's Law of Headlines Apply Here? No. At least not strictly speaking. The dam is in no danger. The spillways are the problem. The main spillway is badly damaged, and the emergency spillway was in some danger of collapse on Sunday. The main spillway is a long straight concrete chute with a gate at the top to regulate the flow. If the erosion in this spillway worked its way up to the top, it could damage that gate and operators would lose the ability to control the outflow. The emergency spillway is a low concrete wall with a hillside below it. Its top is lower than the dam top, so water will go over this wall (and did on Sunday) instead overtopping the dam itself. The worry here is that erosion of this hillside could cause the wall to collapse. Both spillways are separated from the dam by a large hill. Even if they failed, the dam would survive. So there wouldn't be a flood of all 700 vertical feet of the reservoir, but there could be a flood of 30 feet from the emergency spillway. Of course if you were in the path of that flood, the distinction between the "dam" and the "spillway" would be small consolation. The Metabunk page that seanp2k2 linked has some good information and discussion: https://www.metabunk.org/oroville-dam-spillway-failure.t8381/ https://www.metabunk.org/oroville-dam-spillway-failure.t8381... And the YouTube video that clamprecht linked has a good view of the dam and spillways on Sunday: https://www.youtube.com/watch?v=q2YHGR3kVLk&t=2m24s https://www.youtube.com/watch?v=q2YHGR3kVLk&t=2m24s
- chris_7 10y agoWhat ever happened to the Mosul dam? Stories from about a year ago made it sound like collapse was imminent, but it hasn't happened yet. Did they do repairs, or are they just unsure when it will happen?
- yohoho22 10y agoThe New Yorker did a Reporter at Large on it last month: http://www.newyorker.com/magazine/2017/01/02/a-bigger-problem-than-isis http://www.newyorker.com/magazine/2017/01/02/a-bigger-proble... Sounds like many are still worried about it, but there's really no consensus.
- clamprecht 10y agoSeveral pilots have published videos of overflying the Oroville Dam. Here's one from a guy who makes some good videos: https://www.youtube.com/watch?v=q2YHGR3kVLk https://www.youtube.com/watch?v=q2YHGR3kVLk The money shot is at 2:25
- mabbo 10y agoThat's a lot of boats up just past the dam. I'm surprised their owners aren't hastily trying to get them out of the water. If the dam fails in a major way, god only knows what will happen to the boats...
- S_A_P 10y agoInsurance claims.
- TazeTSchnitzel 10y agoMight insurance exclude this type of event?
- clamprecht 10y agoIf they deem it an "act of God" (whatever that means), it could be excluded.
- Stratoscope 10y agoNo one is worried about the dam failing. The emergency spillway is the problem. It's the hillside you see in the video with water flowing down it, to the left of the main spillway. If the emergency spillway failed, it could lower the water level in the reservoir by 30 feet. That would be catastrophic downstream, of course, but probably wouldn't have much effect on the boats.
- mabbo 10y ago> No one is worried about the dam failing My wife, a Water Resources Engineer, is. If the damage to the spillway starts to move sideways, or uphill too far and too deep, you could see the main dam get damaged. It's not as likely as the emergency spillway dropping things 30 feet, as you say, but it's still on the table as a worst-case scenario here.
- dkarapetyan 10y agoWill a lot of infrastructure survive the new weather patterns?
- snarf21 10y agoNo, we've done a very poor job of even keeping up with maintenance in this country. Plus we've push the boundaries of building where we shouldn't. It won't end well for a lot of people.
- erikpukinskis 10y agoI never considered it, but maybe climate change will help clear some of our waterways of harmful dams.
- maxerickson 10y agoBad news, significant flood control+reservoir dams will certainly be rebuilt. So if you are rooting for big dams to be destroyed by weather, you are just rooting for short term harm and suffering, there won't be any long term changes to the river systems.
- jessaustin 10y agoThis certainty is unwarranted, in the recent political context.
- maxerickson 10y agoBeing utterly indifferent to thousands of lives being massively disrupted is unwarranted in pretty much any context.
- erikpukinskis 10y agoI'm not indifferent. I just made an observation. Such changes would come with pros and cons. Many lives would be saved by the removal of dams. Perhaps you are indifferent to the lives that were disrupted by the creation of the dams?
- jessaustin 10y agoThat's pretty fuckin' rich. With the possible exceptions of wars and nuclear-plant meltdowns, nothing disrupts lives on the scale of large dams. I didn't vote for the Orange One, but this is why he won.
- maxerickson 10y agoIf it helps, I'm not coastal or elite. It's certainly a fair criticism of my phrasing, but having your home washed away due to weather is quite different than being compensated to uproot.
- ransom1538 10y agoOroville dam feeds into the Feather river, the Folsom dam feeds into the American river. Here is the kicker: both the American and Feather feed the Sacramento river - a major bottle neck. Folsom dam has turned on the spill at insane rates the past few days. I wish people living in Sacramento county (my parents) would take things more seriously. https://cdec.water.ca.gov/cgi-progs/queryDaily?s=FOL&d=13-Feb-2017+03:47&span=1month https://cdec.water.ca.gov/cgi-progs/queryDaily?s=FOL&d=13-Fe...
- stuckagain 10y agoSacramento will inevitably be destroyed without warning when an earthquake strikes Folsom. Folsom dam is basically a trade where Sacramento gains temporary flood relief in exchange for a certainty of being wiped out by the instrument of that relief. There is a strong economic argument that this makes good sense.
- Bud 10y agoThere are no major faults in that area, however. Folsom is on very seismically-stable ground.
- moocow01 10y agoWell first of all Folsom has little to no seismic activity nor does Sacramento. If an earthquake hit Folsom hard enough to impact the dam Im pretty sure the bay area would be eviscerated. But if the dam was to falter, the water would actually just go into Lake Natoma and sit behind Nimbus dam rather than turning Sacramento into a lake. Even if both dams failed fully or partially, Sacramento levies would experience an increase in flow and volume. You could presumably have a breach in the levies in one or more places but one thing to know is that much of the levies that surround downtown Sacramento are rated at 500 year partly due to the capitol being in Sacramento.
- NDizzle 10y agoThanks for putting this together. Keep me in your thoughts, guys. There's a lot of misinformation about what's going on up there. I'm in Yuba City, 2 miles away from the feather and 30 ft up. They reduced the mandatory evacuation order but more and more emergency personnel are arriving. There are (unfounded at the moment) local reports of water seeping underneath the emergency spillway weir.
- mathgenius 10y agoWhat is the point of all this data and analytics if the author does not even speculate on an answer to the question that is being asked?
- mxfh 10y agoWould it be feasible to dig out another minor temporary overspill or diversion out of the basin into another one somewhere far away from the dam, and more importantly the emergency spillway? Dry Creek basin seems to have some points were it's just a few meters of a hump over the emergency spillway level. https://ngmdb.usgs.gov/maps/topoview/viewer/#16/39.6744/-121.5609 https://ngmdb.usgs.gov/maps/topoview/viewer/#16/39.6744/-121... https://opentopomap.org/#map=17/39.67423/-121.55954 https://opentopomap.org/#map=17/39.67423/-121.55954 https://opentopomap.org/#map=16/39.65270/-121.54263 https://opentopomap.org/#map=16/39.65270/-121.54263
- karlkatzke 10y agoIt's unnecessary. The current emergency spillway is already on the other side of a hill made out of bedrock from the dam itself. All of the concern about the 'failure' is a matter of loss of control of water release, not of breach of the main dam structure.
- mxfh 10y agoI thought the main danger, and reason for evacuation, was a potential uncontrolled failure, due to headward erosion, of the emergency spillway dam structure. (Thats the structure between the regular spillway and that parking lot) https://twitter.com/TaberM_PE/status/831149440262164480 https://twitter.com/TaberM_PE/status/831149440262164480
- karlkatzke 10y agoYes -- which would only result in the loss of control of the amount of water above the level of the bottom of the spillway, or the bedrock under the spillway. That's maybe the top 30 feet at the most. While that's still a lot of acre feet, and it would create a 'wall of water' situation in the first surge (hence the evacuation), it's not as significant as the dam failing and the entire reservoir emptying through it.
- adevine 10y agoI'm sure this is a stupid question, but would it be possible to build essentially a large "siphon", so that the discharge of the water didn't result in erosion directly below the spillway? Seems like it would be pissing in the ocean (or I guess that analogy in reverse?), but when I saw the newsreels of the helicopters dropping bags of rocks into the spillway hole, that also seemed like it would take a couple thousand of those drops to make a difference.
- Symbiote 10y agoI realise this is done to show off the ATSD tool, but it would also make a really good example using a Jupyter Notebook. GitHub will process and render those itself. Example: https://github.com/benlaken/Comment_BadruddinAslam2014/blob/master/Monsoon_analysis.ipynb https://github.com/benlaken/Comment_BadruddinAslam2014/blob/...
- Fiahil 10y agoIt looks like someone had spend quite some time doing this on working hours. It is to showcase something ("where is the ad?"), or someone asked and paid for this analysis?
- ebcode 10y agoThe ad is in this sentence: "Additionally, this article illustrates how publicly available data from the California DWR can be easily loaded into the non-relational Axibase Time Series Database (ATSD) for interactive analysis with graphical representation of open data published by government organizations."
- jimmcslim 10y agoThe ad is also in the URL: https://github.com/axibase/atsd-use-cases https://github.com/axibase/atsd-use-cases ... Still, its a TSDB that I wasn't aware of, so it worked on me! Actually a really practical way of showcasing a product without markitecture brochureware. A GitHub repo and links to Docker images.
- anigbrowl 10y agoIt's great that you're building on this dataset but I'm not sure you're well-placed to pronounce on it being a disaster. Database expertise doesn't make you an expert on civil engineering.
- pm24601 10y ago"Disaster" ? not yet (and I hope not ever)
- rismay 10y agoThis is a very educated estimate. Let's hope it rains less than 2 inches per day.
- astrodust 10y agoAs always, the quirky units Americans insist on using never cease to amaze. Acre-feet. Of course. The only thing missing here is nautical miles and football fields.