The evenly spaced lines are 'control joints' that are common to concrete highway slabs the world over.
http://www.cement.org/for-concrete-...ntraction-control-joints-in-concrete-flatwork
Placing Joints in Concrete Flatwork: Why, How, and When
Reply to #18 (hoping it lands in the right spot?):
This is different: slabs are much bigger in area and have less chance to not crack/fissure; road beds are hi-grade with ditches that are much lower seepage collectors; no ditches to the side here to collect the under slab (huge) seepage; this is more akin to a big canal that is mostly RECESSED, as seen in most historical Oroville pictures I've seen so far, and makes it much harder to keep the concrete seated on a dry substrate; water on top is 10 ft thick roaring at 60 mph and not a tiny fraction of an inch that is barely moving; roads have a crown, this here does not (that I can see on the pix); instead it has a quite steep longitudinal slope, as per historical documents, and that greatly encourages the underslab water to not exit laterally, and instead accumulate for 3000ft.
I'm also trying to see if there is historical pix of the wall top pathways: they might show erosion from lots of rain coming down from the side hills? And then erode alongside the walls? Anybody ever discovered an image of what the "bucket brigade" laborers were fixing, along the (east?)wall pathway? Repairing some pre-existing sidewall fault? Picture?
Please bear w/ me: I am overseas with incredibly expensive Internet at..... "fast" dialup speeds! Perhaps someone w/ real broadband can hunt for historical pix along the above lines?
Cheers
Christian
PS: that pix with the P/U trucks... how did they get there? Through the gates and they have been dry for many days then??? Interesting that this is the first historical pix where I see (apparently damp) stains under the discharge pipe wall outlets! I had assumed they were always dry except when the chute was running and for an unknown time afterwards.
Is there a water table that always reaches all the way up to the recessed "lateral drains" under the slabs? Any other historical images that show damp drains at a time when the lake is known to be below the gates bottom?