PAVEWAY-I sent your twitter images to the Cahills to ask for any comment and am hoping to hear back. They were so nice at answering questions back during the dam crisis. I don't know if the addy is still current or if government goons got to them they way they got to Weiryone, alas. But I will let you know if I hear.
I did find this Cahill interview at PeakProsperity back in 2017. The thing is, I assume nothing at all has been done on this so it is still 100% relevant, and your two twitter images should be regarded as very alarming.
I think it was Bea who said you can't know what exactly is going on without piezometers measuring the flow of groundwater, and the Oroville ones all over that wet area are non functional. Were they ever replaced? The only way to understand that wet area is piezometers....so do we have new ones? I would think it would have been talked about if we did. Maybe they actually do work fine and DWR is lying to say they don't function now, to avoid dealing with it? Who knows.
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link to peakprosperity.com (secure)]
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Quoting: Prayandprepare000 To be honest, P&P, the recent imagery isn't much different than Sentinel imagery from 2016. Minor changes in the green spot, but it's always been there - even at low reservoir levels - and has always been a concern by dam safety people.
DWR has consistently dismissed ANY concern about it as unwarranted and something to do with drainage from the left shoulder 'natural spring' on the dam face. They are convinced that 1) the Zone 2 fill next to the clayey core is dry (based on the few remaining piezometers), therefore 2) nothing is leaking through the impervious clayey core anywhere on the dam, including and especially at the green spot, and 3) nothing is leaking past the drain curtain into the Zone 3 fill of the downstream face, therefore 4) the green spot is superficial and does not indicate ANY internal seepage through the clayey core or past the drain curtain.
See slide 6 of their piezometer presentation from 2019 for those dam details:
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link to water.ca.gov (secure)]
DWR did install some additional piezometers in 2019-2020, but these had to do with concern about leakage through the (fractured/rotten) bedrock and grout curtain under the dam core and/or some of that leakage bypassing the drain and seepage collection system. They indicated that these piezometers showed nothing unusual and increased flow in the drain curtain/seepage collection system was normal (10 gallons per minute) and only increased during periods of significant precipitation on the dam irrespective of reservoir levels.
I think the Cahills were aware of the new piezometer project and results. That project addressed core/bedrock seepage but it didn't explain the geometry or uniformity of the phreatic surface on the downstream side of the dam during periods of high precipitation. So I imagine they would still have concerns, but nobody can do anything if DWR isn't interested in measuring those specific things.
Worse yet, there will be another earthquake in that region
eventually that seriously rattles the dam. I'm not talking about a M2.1 during refilling, but a real California earthquake. Without a proper sensor network on the downstream side, DWR will not be able to explain why or where damage may have occurred if it does. They can only say that damage
did occur by observing increased flows in the drainage and seepage collection system. Big deal - that won't be of much help if you have no idea
where the damage is located. They'll be forced to install even more piezometers or drill new inspection borings... providing they have the ability and resources
after a significant earthquake. I seriously doubt that - DWR will be paralyzed if they have to deal with multiple dam/canal/levee emergencies all over the state at once, and Kiewit isn't going to chopper in to fix anything on time or under budget. The immediate cure is to drain the reservoir if damage occurs, but below 815' they'll have to rely entirely on the hydro plant or the tiny river outlet to drain it, which will take
weeks. And good luck with that if the hydro plant is damaged or the downstream channel is plugged. Or if that happens during winter/spring rainy season.
Point is DWR is winging it and repeatedly saying the green spot poses no immediate danger (which is probably true). But it exposes their general ineptitude for operating and maintaining that dam - and their proclivity for doing it on the cheap or delaying it as long as possible AND doing it in secret - because 200K downstream victims are disposable people that don't need to know DWR's critical infrastructure secrets. You might be terrorists! The 'experts' said everything is OK. Trust the government -
they got your back.
One earthquake is all it will take to dissolve their PR-fueled illusion of a "perfectly safe and well-maintained dam." Hell, another swipe of an atmospheric river this year might do the trick, too. It really doesn't matter - DWR will cry that it's a one-in-ten-billion year event that nobody on earth could have possibly predicted. Nothing will ever be their fault. Fukushima/TEPCO all over again. Oh, and could FEMA please send another $50 billion federal clown-bucks so they can rebuild all their crappy water infrastructure. This is so... predictable.
