New Catholic Online article:
(more pics in article…plus interesting technical FERC/DWR history on uncertainty in risk of failure - yet no repairs for 2017.. mentions FEMA noted legal risk of dam owners in reference).
(note the steel plates on the spillway bridge and entrances + traffic flaggers. Steel plates at locations where "under bridge" supports are cracking/spalling).
The condition of the gate area is perhaps worst than I thought. I had stated that they should maybe build a new spillway adjacent to this one, and then, once in service, rebuild this spillway to use as an emergency spillway. It seems that they might want to consider that approach. If they don’t repair the gate area, there will be a failure and people will be lucky if it only drops the lake level to 813 feet (presumed to be the floor of the gate structure excavation.
Thanks for your continued research and posting.
That’s a good graphic. Very informative.
Hey ER:
So the graphic shows the most noted crack data for the third and fourth area(s) from the left. Does that mean those areas have more cracks or just that they got “good” measurements there. As I recall they were unable to get measurements on some of the rods due to the technique not returning believable data.
ER333:
Hope your ticker is doing OK. Please don’t get too stressed out. The world needs your experienced perspective and insight.
I have a couple of questions regarding your recent posts.
The painted red crack shown in post 3671 is from a Feb 2015 DSOD report, isn’t it?
If so, at that time the FCO gates hadn’t been used for years, and the reservoir was below the FCO inlet, so there was no head pressure at all on the gates or structure. If the crack was growing then, it had to be from concrete shrinkage or settlement and drying of the foundation. I think I recall Scott Cahill saying that he thought the back side of the FCO foundation was partially built on fill, so perhaps that could have something to do with it.
If the FCO structure was cracking in 2015, one can only wonder how it’s working now. The gates were recently under greater static head pressure loading then ever before, and they’ve been dynamically opened and closed more times this year than in the last decade. Also, that heavy truck traffic no doubt stressed the structure way more than the pickups with speed boat trailers that it was designed to carry.
Question: if 2 of the 384 anchor tendons “failed” in 2010, how did they determine that? Did they get no ultrasonic reflection at all? Were these rods completely fractured? Or did they rate 1/8” rather than just 1/16” on the ultrasonic test?
I too would very much like to see how they went about coring and replacing them.
It seems strange that 2 rods failed to the point that they needed to be replaced a decade or so ago, but none of the other 382 have structurally failed since then. Was there a QA issue with just those 2 rods, or were they somehow tweaked due to their position relative to the cracks in the FCO structure? Were they both adjacent rods from the same gate? One might think that other adjacent rods would have failed by now with all the recent high stress dynamic loading on the FCO.
There are many questions to be raised if and when DWR becomes more accountable. With Oroville’s DSOD “regulators” just being just another internal division of DWR, it appears that this accountability will have to come from outside independent scrutiny. Please keep up the good work as you are able, and the scrutiny will be applied.
FYI - FERC IS RETROACTIVELY DELETING FERC/DWR COMMUNICATIONS DOCUMENTS/REPORTS ON THE OFFICIAL FERC PUBLIC DATABASE. The documents that have found to be deleted are critical reference doc's on the Catholic Online articles that reference the Anchor Tendons (reports & communications between FERC/DWR).
The doc's just disappeared - no CEII status change, nothing. They no longer exist on the database. HERE ARE AT LEAST THREE OF THE DOCUMENTS DELETED:
20000509-0242(986809) Prelim Anchor Tendon Ultrasonic testing report noting "no significant defects were noted" (this is a direct contradiction in what DWR is stating to FERC in crack defect findings verses the actual Ultrasonic testing results in 20000419-0130 -i.e. falsehood told to FERC)
20000419-0130(977645) Anchor Tendon Ultrasonic testing report with crack identifications report
19990322-0490(533695) Anchor tendon LLNL Ultrasonic vs high power ultrasonic testing discussion communications