post#2393
How many slabs per side drain?
Looks to me like only 1 side drain for every 2 slabs?
Not sure...
(also note at least one on each side with no flow,
I suspect these indicate complete drain failure)
Abb's drawings of drain system..
Quick answer: 1 wall drain per 4 slabs & wall drains spaced 200ft apart.
Evidence: The image at the FRpost below clearly reveals the drain system design & spacing per slabs. You can see 10 drain cracks for every 4 slabs. If the slabs were exactly 50 ft long (ignoring any radius factor at the spillway curvature transition), this would be 10 drains for 4 slabs with an sidewall outlet every 200ft. Note: these drains are mirrored & aligned on the other half of the spillway (cracks verify this alignment). Thus you see sidewall outlet drains aligned down the spillway.
HerringBone Drain Pipe - Fracture pattern in Main Spillway...
This FRpost image set shows the "missing water" issue going back to 2009. There are other images that show this same issue in 2007. So for 10 years they had advance warning that there could be a problem (besides the constant repairs in the "missing water" area).
Years of Warnings at Blowout Area? Missing drain water/slabs being repeatedly repaired at leakage..
= = = Regarding Post 2,393 ("The Mercury News" Chico-Enterprise Record - photo w/ spillway defect asking DWR for comment).
Something Interesting... The base photograph in "The Mercury News" article states 2 photos were taken by their news photographers Jan 13 and Jan 27. The image in the article is the Jan 27 photo. This Jan 27 photo was placed on SmugMug by ChicoER where you can sell photos online. I purchased an electronic copy of this photo from SmugMug to get the best forensic investigative evidence (in pixel resolution analysis). This same base photo started making the rounds on discussion/engineering forums in failure analysis. Many different markups made on each photo. (note: FRpost 2,092 image was from a purchased copy & specific graphics added for failure analysis & discussion for our FR thread).
As groups progressed (including the forensic discussions in FR) the mounting evidence was becoming strong on the failure mechanisms at play regarding the spillway "blowout".
Then a news story where DWR is asked about this photo & the "hole in the concrete" (the defect) comes out March 11.
Word must be getting around to where the news people are picking it up. OR they are perusing forensic discussion websites/forums.
Identical base image in FRpost 2,092, March 1, 2017:
Same missing waterflow in drain near pre-failure blowout area. notice the defect in the concrete slab seam at/near the pre-failure blowout area.
