hawkeye_wx Posted February 13, 2017 Share Posted February 13, 2017 Their goal is to get the lake level down 50 feet by Thursday, to about the same level it was at before the last round of storms. This time, however, I'm assuming they'll keep the main spillway flow at 100k cfs, which should greatly increase the chance they can keep the lake from rising back to max. Link to comment Share on other sites More sharing options...
janetjanet998 Posted February 13, 2017 Author Share Posted February 13, 2017 just saw a shot of the emergency spillway... The erosion is really bad and very deep it was even eating south back towards the main spillway Link to comment Share on other sites More sharing options...
ValpoVike Posted February 13, 2017 Share Posted February 13, 2017 Has anyone seen any photos, post-100cfm, of the gash in the main spillway? I think that is the biggest issue now that the level is down below the emergency spillway. If that erosion continues unabated, there will be no good choice later this week...either slow down the rate and deal with a potential collapse of the emergency spillway, or keep the flow rate and risk a total failure. I don't understand how they are holding on the position that the dam itself is in no danger. If the main spillway erosion expands significantly, it appears to me that the entire structure is in danger. Link to comment Share on other sites More sharing options...
janetjanet998 Posted February 13, 2017 Author Share Posted February 13, 2017 1 hour ago, ValpoVike said: Has anyone seen any photos, post-100cfm, of the gash in the main spillway? I think that is the biggest issue now that the level is down below the emergency spillway. If that erosion continues unabated, there will be no good choice later this week...either slow down the rate and deal with a potential collapse of the emergency spillway, or keep the flow rate and risk a total failure. I don't understand how they are holding on the position that the dam itself is in no danger. If the main spillway erosion expands significantly, it appears to me that the entire structure is in danger. The pics I have seen so far is that there has been no more erosion back towards the dam from the damaged spillway...perhaps some down below but the erosion under the emergency spillway appears to be more the just loose dirt...maybe not solid bedrock but loose rock material and that eroded they said the flow down the emergency spillway is hitting a large bedrock and hence the spray here is a pic of the emergency spillway which they said was desgined to handle 250,000 cfs.... 36 hours of 8-12,000 cfs did this Link to comment Share on other sites More sharing options...
ice1972 Posted February 14, 2017 Share Posted February 14, 2017 11 hours ago, janetjanet998 said: The pics I have seen so far is that there has been no more erosion back towards the dam from the damaged spillway...perhaps some down below but the erosion under the emergency spillway appears to be more the just loose dirt...maybe not solid bedrock but loose rock material and that eroded they said the flow down the emergency spillway is hitting a large bedrock and hence the spray here is a pic of the emergency spillway which they said was desgined to handle 250,000 cfs.... 36 hours of 8-12,000 cfs did this Its the first time its ever overtopped........the land downstream of the emergency spillway is not engineered probably since it is the last relief......hence the dramatic erosion....still it seems far enough away from the main dam to actually be working as intended....also people should know that the earthen dam actually has an impervious core of concreate extending from the top of the dam downward at a slight angle toward the lake.......its not like its just earth throughout.......theres also a nother impervious layer lakeward of the main one that acts to provide redundancy in the system.....on the downstream side there are numerous drainage reliefs throughout the earthen structure to keep it dry and stable......the evacuations are probably a good idea but I think the dam holds....... Link to comment Share on other sites More sharing options...
ApacheTrout Posted February 14, 2017 Share Posted February 14, 2017 7 hours ago, ice1972 said: Its the first time its ever overtopped........the land downstream of the emergency spillway is not engineered probably since it is the last relief......hence the dramatic erosion....still it seems far enough away from the main dam to actually be working as intended....also people should know that the earthen dam actually has an impervious core of concreate extending from the top of the dam downward at a slight angle toward the lake.......its not like its just earth throughout.......theres also a nother impervious layer lakeward of the main one that acts to provide redundancy in the system.....on the downstream side there are numerous drainage reliefs throughout the earthen structure to keep it dry and stable......the evacuations are probably a good idea but I think the dam holds....... There's no way to know if that spillway is going to hold if water overtops it again. Erosion has a way of doing unexpected things. Link to comment Share on other sites More sharing options...
janetjanet998 Posted February 14, 2017 Author Share Posted February 14, 2017 ok they have downgraded the equation to a "warning"..um ok I think they should decrease flows out of the main spillway soon....the next storm won't have the runoff as the last one and the ones after that look cold and snowy I think the main spillway is eroding more on the north side about 1/2 way down from the now waterfall Link to comment Share on other sites More sharing options...
hawkeye_wx Posted February 17, 2017 Share Posted February 17, 2017 They've managed to bring the lake level down 42 feet, and it continues to fall, so I don't think they'll have any issues during the latest train of storms. Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 18, 2017 Share Posted February 18, 2017 The models and projected rainfall amounts increase....yet they decrease outflow even more to 70,000 cfs. heavy rain moving in.. Look out belowwwwwwwwwwwww Link to comment Share on other sites More sharing options...
Chinook Posted February 18, 2017 Share Posted February 18, 2017 Los Angeles area with rain and flash flood warnings all over the place. The Santa Barbara coast mountains have gotten 4" today all aboard the rain train Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 18, 2017 Share Posted February 18, 2017 I'm surprised of the relatively low Inflow amounts all day today at the dam. Maybe their using extra pumps upstream , that their not telling the public. It's basically been 30,000 CFS Inflow every hour today...at a time when rainfall the last few days should of normally caused some spikes by now - https://cdec.water.ca.gov/cgi-progs/queryF?s=ORO&d=17-Feb-2017+20:59&span=12hours another interesting bit of info I heard earlier this week.... the biggest portable pumps these days can pump out 20,000 CFS per second. Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 18, 2017 Share Posted February 18, 2017 i guess this is why their keeping the Inflow diversions hush hush... locations to the SW are flooding now...the only place they could of diverted, if they wanted to. widespread flooding in Sac as well. (unconfirmed) Maxwell, CA - Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 18, 2017 Share Posted February 18, 2017 Latest image from Williams, CA. The place where they evacuated people from Maxwell to Link to comment Share on other sites More sharing options...
hawkeye_wx Posted February 18, 2017 Share Posted February 18, 2017 The lake is down nearly 50 ft now, and still slowly falling. The inflow during the latest storms is much lower than during the last storm train. Models show the fire hose aimed at the Oroville/Tahoe area on Monday, but that one system probably won't be able to fill the lake back up. Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 18, 2017 Share Posted February 18, 2017 Their saying the main spillway is partially breaking up along the left side. 40,000+ cfs Inflow the last 2 hours straight. the bigger problem is downstream along the Sac river...where the rivers will be peaking from yesterday's rains...at the same time heavy rain comes in tomorrow. double whammy...for places that are already flooded out. So it could very well be a bigger story downstream. Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 18, 2017 Share Posted February 18, 2017 several more reports of the main spillway breaking apart rapidly. (scanner) and some new, impressive photos of Maxwell, CA .... (Fox40) https://www.facebook.com/fox40/posts/10154410503712039 Link to comment Share on other sites More sharing options...
janetjanet998 Posted February 19, 2017 Author Share Posted February 19, 2017 after this next soaker a pattern change on the GFS a drier NW flow with monit colder systems 8 station rainfall index 70.7 220% for the date record 88.5 should end up well over 75 when this event is done http://cdec.water.ca.gov/cdecapp/precipapp/get8SIPrecipIndex.action Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 19, 2017 Share Posted February 19, 2017 holy smokes, somebody was able to sneak in and get a recent image of the spillway today ! It's not even going down it anymore. Props to twitter.com/yamphoto Link to comment Share on other sites More sharing options...
Jonbo Posted February 19, 2017 Share Posted February 19, 2017 That's eroding towards the main dam, right? Worst case scenario seems more likely.... Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 19, 2017 Share Posted February 19, 2017 It sure is. And California media is barely mentioning anything. over a 100 inches of snowpack...just to the north and east. With another 'atmospheric river' incoming. http://www.weatherstreet.com/weather-forecast/california-snow-cover.htm Link to comment Share on other sites More sharing options...
Jonbo Posted February 19, 2017 Share Posted February 19, 2017 https://www.facebook.com/FoxNews/videos/10155128737211336/ Fox News has a live stream going at the spillway. Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 19, 2017 Share Posted February 19, 2017 unbelievable. this should be a crime what they did 3 days before last Sunday - https://cdec.water.ca.gov/cgi-progs/queryF?s=ORO&d=9-Feb-2017+14:22&span=12hours look how they were playing around with the Outflows, when getting Inflows of around 160,000 maybe they'll delete the link next...who knows. Link to comment Share on other sites More sharing options...
cstrunk Posted February 19, 2017 Share Posted February 19, 2017 Yeah, it's a serious situation. But I seriously doubt anyone committed any criminal acts. I'm sure these employees were following engineering guidelines. They have a responsibility to store water as well as release it, and after the drought that has plagued the area I'm sure they were in the mindset of keeping a higher pool of water in the reservoir because of it. But the only issue was because of the spillway failure. If mistakes were made it was probably in the inspection process of the structure, but I don't think any of that would constitute being a criminal. Otherwise it's an act of God and they tried to do the best they could to minimize catastrophic failure. If you want to blame anyone, blame the government for not spending enough money on our infrastructure. Go out and look at the number of high-risk dams (and bridges, etc.) in this country. From the conspiracy theory tone of this thread I'm sure you all will be very concerned. Link to comment Share on other sites More sharing options...
NCWX Posted February 19, 2017 Share Posted February 19, 2017 The live feed is amazing to watch. Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 19, 2017 Share Posted February 19, 2017 Link to comment Share on other sites More sharing options...
janetjanet998 Posted February 20, 2017 Author Share Posted February 20, 2017 it appears the main slug will go just south of the Oroville area this time Breaking: TID preparing to open Don Pedro Reservoir spillway as early as 3 p.m. Monday Read more here: http://www.modbee.com/news/article133793724.html#storylink=cpy Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 20, 2017 Share Posted February 20, 2017 if you look at the main dam and watershed leading in...the heavy rain is falling directly over the watershed / tributaries . the dam is located like 20 to 30 miles NE of where the town of Oroville shows up on the map. Link to comment Share on other sites More sharing options...
janetjanet998 Posted February 20, 2017 Author Share Posted February 20, 2017 57 minutes ago, Sophisticated Skeptic said: if you look at the main dam and watershed leading in...the heavy rain is falling directly over the watershed / tributaries . the dam is located like 20 to 30 miles NE of where the town of Oroville shows up on the map. Yes but the main band started south and will work its way north..then head back south again..radar confirms this yesterdays models had it overlapping the Oroville/drainage area the whole time because it started more north so totals may be a couple inches less (still 3-10 though) expect precip to increase soon as winds turn more SSW creating uplift 8 station index now 72.1 223% of normal for the date Link to comment Share on other sites More sharing options...
janetjanet998 Posted February 20, 2017 Author Share Posted February 20, 2017 22 hours ago, Jonbo said: That's eroding towards the main dam, right? Worst case scenario seems more likely.... it stopped eroding back they were concerned it would that is why the limited outflows to 65K then 55K as it was going over the ES...then they spiked that up to 100K when they had no choice after days at 100K no more erosion up the hill as far as I can tell Link to comment Share on other sites More sharing options...
Sophisticated Skeptic Posted February 20, 2017 Share Posted February 20, 2017 the Low is now projected to be significantly weaker than progged 24 hours ago. 993'ish coming ashore. now 1003'ish maybe they dropped some dry ice out there, over the pacific. seems like quite a dramatic change in strength from a storm that was about 24 hours from landfall. I haven't seen such model error in 20 years. Link to comment Share on other sites More sharing options...
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