Emergency: California’s Oroville Dam Spillway Near Failure, Evacuations Ordered

Breitbart ^ | Feb 12, 2017 | Joel B. Pollak1

[EarthResearcher333]

Piece by piece Clues to the Erosion Channels under the Green Wet Area - Clean Surface of dam with no erosion channels vs Dense Erosion channels - Linked?

DSOD had good reason to note of a "slope stability" issue in their 2105 report. Here are side-by-side images of a Clean surface of the dam and the dense erosion channels forming on the dam's surface. Same elevations, same left side of the dam. (side note - note the revealed construction layering strata lines in the Clean image).

Both of these areas of the dam have been exposed to the same weather since 1967, same heat/cold, same rains. The "normal" time weathering of the intended Zone 3 fill design is revealed in the minor weathering of finer materials, revealing minor areas of cobble rock, in the "Clean surface". The slope remains stable and resists even the strongest of rains endured over 48 years. At the Dense Erosion channel section, it too has been exposed to the same weather & rains. Yet, over 48 years, these dense erosion channels have been forming slowly, gradually.

Both of these areas were constructed in compacted layer fill at the same time in 1965 as these images are at the same elevation section. The same sands, gravels, cobbles, and boulders comprising the Zone 3 fill "shell layer" were laid in 2 ft "lifts" and compacted. So there is no evidence that a difference in construction & materials composition would be a likely mechanism tied to the "erosion channels". The "differential" key, between these two areas, is that the "erosion channels" originate at a "long established wet area" (as named/stated in DSOD inspection reports).

Yet there is a "clue" that helps answer the differences between these areas in the light of evidence to an underlying mechanism to the formation of the "erosion channels".

[EarthResearcher333]

EH: "Apparently there is an alternative explanation that involves water seepage taking out some of the material, but leaving other (generally larger) material behind."

Correct

EH: "If water HAD shown as a surface flow it would have been cause for an immediate loud alarm, and it certainly would have been documented. There is no record of that ever happening."

Correct

EH: "A side issue I have not seen addressed is the SIZE of these channels."

Channel widths: avg: 6.69ft, 5.72ft, merged: 10.68ft, 20.55ft, (they get wider as they combine/merge as in the two larger numbers).

EH: "Another side issue I have not seen mentioned is the number of these channels, and the fact that they seem somewhat evenly spaced and approximately the same size. This is not what I would expect from a single point source."

Correct

KCB: "The lower strata, when saturated, would sometimes be also exposed to rain. The rain would repeatedly carry off the “fines”, such a fine sands and smaller grained non-organics. As it did so, the larger gravels were striated into rivulets due to the action of the small grains being carried by water pushing the larger cobbles into stripes."

Precisely Correct

[KC Burke]

One comment on what you wrote. In today’s standards, it is rare to see engineered fills placed in two foot lifts or layers. Normally you see fills placed in 0.67 lifts or possibly 1.33 foot lifts but rarely in 2.0 lifts.

I will add that dam construction with massive equipment may allow lift thickness for compaction beyond what I would see in roadways, runways, and large heavy equipment pads.

[KC Burke]

Thanks.

[EarthResearcher333]

DWR is was not publicly speaking of these erosion channels. Only in DSOD reports were these noted. However, with the publicity of the "unresolved" green wet area being exposed in photographs & articles, DWR has been asked strong questions by the public on the Greening and on the Erosion channels in the recent community meeting(s).

[EarthResearcher333]

Piece by piece Clues to the Erosion Channels under the Green Wet Area - Subsurface saturation? - Combined with Rain? - Causing "fines" erosion? - Wide area saturation?

EternalHope & KC Burke reveal key pieces to the formation of the "erosion channels". In order for the Zone 3 finer material to be removed there has to be a mechanism that disassociates the prior "compacted" & historical time weathered "consolidation" of the fines. As demonstrated in the "Clean Surface", the surface fines are resistant to erosion as the downward absorption of rainfall continues to slowly percolate within the Zone 3 "pervious" design, but still maintain the same "consolidation" vector to the structure. ONLY if there is a subsurface "effect", will this "consolidation vector" be disrupted. Subsurface saturation is a primary example. A "wicking" or "capillary" action will moisturize from below in the saturation, and then rainfall on the surface will percolate to meet this zone. There are actually "two" directions "fines" may thus be eroded. One is at the surface in the downhill slope vector. The other is if the "subsurface saturation" mechanism is also causing deeper percolation and evacuation of "fines". This is the same layered effect of rainfall to a saturated subsurface, except it is a saturated subsurface with another saturated subsurface - all being influenced by a downslope vector. So where would the "subsurface fines" migrate to? Or is it "subsurface fines" changing the percolation characteristics such that saturation may flow easier to deeper levels - including to the bottom horizontal "drain zone" layer?

A "wide area" saturation allows the natural formation of "erosion channels" looking to be from gravity & natural "meandering" random development vectors. However, this is very subtle.. there must be a "mechanism" to "free" the prior consolidated "fines" to allow this dense formation of erosion channels. Thus, this "wide area" subsurface saturation subtlety is overlooked, is because the focus of attention is just on single erosion channels alone.

More later…

[mad_as_he$$]

Seeing your post regarding how the dam construction was halted every Winter brought a question to my mind.
It is as follows. Have you found any reference regarding how the structure was prepared for the Winter? Was the clay area capped with more typical fill or covered to protect it; then removed in the Spring?

It occurred to me that the could be a break in continuity of the clay barrier if the cap material(if they did cap it) was not completely removed in the Spring. Seems to be a basic simple question but in the case of this project they appear to have overlooked some very simple things.

[EarthResearcher333]

"Seeing your post regarding how the dam construction was halted every Winter brought a question to my mind."

From the records, they never really stopped. They worked around the clock with night lighting. However, in certain "stages", they had to relocate the massive 76inch wide belt conveyor system to the next planned strategic location. This "relocation work" took time and created interruptions during the filling/compaction construction.

The more important factor was that certain construction layers were exposed to seasonal rains during this compaction process. Extra hydration of the fill material becomes more dense and less pervious (more resistant to waterflow) in the compaction (actually, it becomes a ratio of compaction AND consolidation from the heavy equipment).

The precise schedule timing of the seasonal rains to the large conveyor system reconstruction to the next large "section" is not specific. The only references is that the DWR construction historical documentary videos identify alignments to certain layers to certain years. (i.e. 1964 for the "hump" section in the toe axis area, 1965 of 22 million cu yds for layer 1, 1966 of 22 million cu yds for layer 2, and 1967 of 19 million cu yds for the third and final layer.

Each layer required a major deconstruction and then reconstruction of the large conveyor system.

So the seasonal rains became part of the densification of "layer" sections of the dam. The best evidential clue to these densification layers have been revealed in prior posts - as internal seepage & saturation lateral water flows align to the layer seams.

[mad_as_he$$]

OK. I missed the fact that they never shut down and latched on the yearly progress and feature notes- ADHD kicked in.

It is a very good observation about the conveyor system(marvel for the time). Compaction, water content/application and lift height would all be key in the process. One would think that with all the moving and transfer of the material that it would be very evenly mixed by the time it was placed on the layer being constructed. However, many things simply refuse to cooperate when deposited; shape, weight and surface roughness all come into play. Clearly something went awry with the process.

Thanks.

[EarthResearcher333]

Piece by piece Clues to the Erosion Channels under the Green Wet Area - How the dam was intended to work - Where does the water go?

To get to the next clue, it helps to see how the dam was designed with respect to water retention and the natural "seepage" through the core and transition zones. The internal water conditions are noted as "phreatic surface" or "phreatic line". This is essentially the water level within the inner sections of the dam.

The dam holds back water from a highly compacted "core" layer of clay-clayey mix (zone 1 - orange in illustration). It was placed in 10 inch lifts, carefully hydrated to a certain percentage ratio, and then compacted with a form of an additional consolidation. Documents state that the net core compaction/consolidation density rivaled or bettered the density of concrete. To structurally protect and to hydraulically protect the "core" layer, "transition zones" (Zone 2) were built on each side of the central core (dark brown in illustration). The transition zones had silts, sands, gravels, cobbles, and boulders (to 15" max). The silts in conjunction with sands formed a semi-block of waterflow. The cobbles, and boulders provided the structural support that the smaller silts sands gravels were confined within. The upstream Transition zone was designed to "heal" the core in case micro defects develop. The seepage into these defects would transport "silts" from the Transition zone and plug the micro defects in the core.

The outer layers are the massive gravity weight layers of the Zone 3 fill comprised of sands, gravels, cobbles, and boulders (to 24" max). The Zone 3 fill "shell layers" are intended to pass water, thus they are called non-pervious. Although waterflow was restricted to a slowed percolation through the smaller fines in the gravels and sand.

A very important Zone layer is the "Drain Zone" (light blue in illustration). The Drain Zone is intended to direct and pass any waterflow that seeps past the transition zones, and the core. As the Drain Zone is comprised of gravels, cobbles, and boulders it has no silts, sand, or clay-clayey material to impede waterflow. The vertical section is 20 feet thick for the vertical "chimney" part of the Drain Zone, and 10 feet thick for the bottom of the dam Drain Zone layer. The dark blue arrows depict the ideal operation of all of these fill zones working as designed. There should be no reservoir waterflow penetration beyond the Drain Zone Chimney in an ideal "phreatic level" or "phreatic surface" curve inside the dam.

On the back side of the dam, the Zone 3 outer shell will respond to rainfall in allowing the rain to percolate downward into the sands, gravels, cobbles, and boulders. This design of percolation is to prevent erosion channels from developing on the outer surface of the dam. Everything works fine as the flow and the construction compaction are in unison to gravity & gradual settlement. There will be minor erosion on the surface, but this is a very long and slow process that keeps the effect retained through the ability of the material to allow rain water to percolate into the consistent strata of sands and gravels.

The two combined dangers that may "upset" this internal percolation design function are (1) high rates of percolation flow (creating saturation pressures) in conjunction with (2) a non-unison vector flow (i.e. a lateral type of pressured flow from "deflection or redirection" instead of the vertical unison alignment).

At this point is where the clues of the Erosion channels start to emerge from of a new "source" of an "unexpected type" of water flow, other than the ideal phreatic level flow, is introduced.

A whole series of internal events start to develop. More later…

[EarthResearcher333]

They used real-time computers to weigh the "mix" on the moving conveyor belt and automatically injected sands and materials to keep the mix within specs "on-the-fly". They never mentioned what type of 1960's computer, but many interesting types come to mind. These were out in the field. They had to be in special large enclosures.

[mad_as_he$$]

Most likely some version of PDP.

One of my uncle’s ran an excavation business during that timeframe. I drove pusher and a towed pan for him in the very late 60’s. We built several earthen dams for farmers. I was always struck by how the dirt moved when dumped or pushed. Clods would move like they had a mind of their own, different types of soil would behave with completely different settling characteristics. Aeration played a big factor. The more you moved it the more air it had and getting it compacted often became a very difficult.

[Jim W N]

Piece by piece Clues ...to get to the next clue

I still think Mr. Green did it in the Billiard Room with a rope. :)

[janetjanet998]

Juan update

flyover of the DAM and green spot
https://www.youtube.com/watch?v=pAWAbslg2vE

[blueplum]

found another video, I don’t know how to capture the charts on surrounding dam levels at mark 1:53. At mark 3:33, Calif-Nevada River Forecast Center: 90% of Calif and 100% of Nevada rivers are rated as extremely above normal levels. Snowmelt equivalent to 1” rain per day last 7 days. Also at mark 6:52, the DWR green area explanation was challenged at the DWR meeting; dam wall slope errosion. Approx 8:32, more questions about blasting to remove solid rock, terracing.

(My question: does terracing affect counterpressure against the dam?)

In other news, Calif is borrowing $500M (I heard only half for the dam the rest for ‘projects’). DWR took out a $300M line of credit, plus initial Fed grant, plus anticipated FEMA funds, brings cost to over a billion from initial estimate of $200M. DWR intends to recap from water customers, no surprise there.

BPEarthwatch video 5/7/2017
https://www.youtube.com/watch?v=I-EFLLiaYZ4

[blueplum]

We can estimate how Cal would fare by looking at what happened to the Sac and San Joaquin valleys from water cannon gold dredging. The riverbeds will rise from fill washing down, the levies will break, ag land will be contaminated, there will be devastation and nobody riding around handing out $20 gold coins:

“It became apparent to the engineers and many others that it was not rising waters that were causing the floods, but it was instead rising river bottoms choking the channels, causing the flooding and impacting navigation.
According to the 1957 book, “The Geography of the Sacramento-San Joaquin Delta, California,” by John Thompson, “By 1866, debris had ended the infamous side-by-side steamboat races along the Sacramento River.”
It also had a dramatic effect upon the farmers and their land, because the mining refuge left from the floods was not the same as the rich alluvium left by the natural annual rise and fall of the river that enriched the soil and increased production.
Instead what came down from the mines were rock fragments of varying sizes and elements. These waters carried mercury, cyanide and other poisons, which could sterilize the soil, kill crops and harm animals and even people...The 1880 book, “History of Sacramento County, California,” presented various details about this flood.
Included in the book were the following words: “At 2 o’clock on the morning of that day, a break was reported in the levee near Lovedall’s (sic) Ranch, on the Sacramento River, the city and Sutterville. Almost immediately thereafter, a section of the levee, some twelve feet in width, washed out, having been completed honey-combed by gophers. The noise of the torrent pouring through the crevasse could be heard distinctly at a great distance. (That evening), the Sacramento (River) was twenty-five feet, 2 inches above the low water mark, higher than ever before known.”
http://www.valcomnews.com/?p=9787

By the year 1870 the population of Cherokee [near Chico] was roughly 7,000 persons. About this same time, the gravel and mud tailings were fast becoming a real problem. These tailings flowed down to the valley farms covering everything in their wake. Dams were built to hold these tailings, but when the muddy mass built up to capacity, they gave way and allowed their contents to flow downstream, covering fields, crops, and everything else in the area.
After the break of a tailing dam, mine representatives would ride through the newly flooded areas, their pockets bulging with $20 gold pieces. At each flooded area they stopped and asked the owner his losses. They paid the named damages in gold—with no argument.
By 1890 a growing resentment against hydraulic mining appeared. Millions of tons of rock and earth from the huge hydraulic monitors had clogged streams, filled rivers, and covered vast areas of agricultural land. In 1893, pressure exerted on the California Legislature- caused the anti-hydraulic mining law to be passed, thus ending hydraulic mining.
http://thetombstonenews.com/the-unsolved-mystery-of-californias-idle-diamond-mine-p1576-84.htm

[EarthResearcher333]

Piece by piece Clues to the Erosion Channels under the Green Wet Area - Did the early dam "saturate itself"? Or "dirt itself"?

The next clue comes from the early days of the dam operation. Something unusual develops. Large areas of Zone 3 fill become "saturated" on the backside of the dam. Even more unusual is that this large "saturation" occurs in two locations. The locations are near perfectly symmetrical adjacent to the center toe axis if the dam. The square surface area of the Zone 3 fill saturated hillside is equal to or larger than the square foot surface area of the "Erosion Channels" today. Where did this water come from? After all, in the perfect dam design, any water from the reservoir that seeps its way through the Core and Transition zones would/should be captured in the vertical "Drain Zone" chimney and out the "Drain Zone" in the bottom of the dam. There should not be a "saturation" of the Zone 3 fill, especially at the surface.

Could rainfall have caused these the large areas of "saturation"? If rainfall were to be the "original" cause, the Zone 3 fill in these areas would have to have been non-pervious with a high degree of silts, soils, or clayey material such that the designed percolation was ineffective or defective. Thus, a heavy rainfall would soak the surface and would not percolate beneath the surface as the silts, soils, or clayey mix would "hold" the water. The original imaging reveals that greening occurred in these large saturated areas. With a non-pervious deposition of moisture retentive silts, soils or clayey material base, and a saturated (water) source, vegetative growth has what it needs. These were the first "Green Wet Areas" on the dam.**

So the question becomes, what came first? The Dirt or the Saturation?

If the Dirt was there first, it had to have been from construction. But how could all those computers controlling the automated conveyor belt system's sand mix rate, to the Zone 3 fill, could have added silts, or soils, or clayey material? Bad programming? Bad Computer? And how did this computer know to do this in a perfectly symmetrical arrangement to form "twin" regions? Or was it from construction error? If so, did drivers of the load dumpers mistakenly take material from the giant fill "dump hopper" to Zone 3 fill instead of the Transition Zone (contains silts) or the Core (contains clays & silts, & clayey soil)? If they did, it had to be perfectly aligned errors to make these "twin regions". The odds of any of these conditions seem far remote, in fact they would say to defy probability.

The "other" wild supposition is - did rain somehow cause "dirt" to be brought to these spots from the tiny traces of soil particles within the Zone 3 surface area? This would defy the downward rain percolation characteristics of the Zone 3 fill. In addition, for all of the tiny traces of soil particles in the Zone 3 fill to be gathered up and deposited in the dirt spots, would require such a high concentration of collection (from tiny trace amounts) of a large volume of Zone 3 fill such that very "smart" rain would have to "collect", "redirect", and "go vertical upwards" to the dirt spots.

If the saturation was first, how did the dirt get there?

Could saturation result in the dirt spots? Yes. Where's a high concentration of dirt? The transition zones and the core. Then where's the original water source for this saturation? The reservoir. Why didn't the Drain Zone capture the water? It clogged in two areas above from the transport of silts, soils, clay & clayey material What caused this strong seepage flow? The core developed settlement leaks from longitudinal cracks. How did the water saturate the Zone 3 surface instead of curving down to the bottom to the horizontal drain zone? Good question - more clues on this later. What happened to these original settlement leaks? The upstream Transition zone sealed the leaks with its silts & sands flowing into the core

Could this be the same dynamic mechanism at play in the current "Green Wet Area"? Good question… what do you think?.. more clues/evidence later...

**note: a larger image & RGB coloration matching to trees, grasses, and other vegetation in the larger image reveal the clear greening of these saturated areas. The zoom version here is less distinguishable due to the low resolution & blurring.

[abb]

Atmospheric relative humidity is a factor on compaction. I had a project where we tried everything to get a sand/clay soil up to spec. After a cool front pushed through, and the humidity dropped (South Louisiana), compaction was achieved. I was driving a sheepsfoot, and could see it happen.

[mad_as_he$$]

Good point. The climate around Oroville is relatively low humidity in the Summer and higher during the Winter(rainy season). Looks like the patent for sheepsfoot roller(s) was granted in 1950 so it is very likely they were in use at Oroville. That was another thought I had was - how were they compacting the material?

https://www.google.com/patents/US2674165

Seems clear from the work of ER that there is some “leakage” in the dam structure.

[EarthResearcher333]

Piece by piece Clues to the Erosion Channels under the Green Wet Area - The Aftermath of the "Saturation", the "Dirt"

This next clue is the aftermath of the "saturation". It left a significant density of "fines" (aka "dirt") that was deposited on the surface of the Zone 3 fill. So how can "dirt" get to the surface? The saturated water flow, that was carrying the "dirt", had saturation pore pressures and flow rates such that it could elevate the particles to the surface. The density in the color reveals how much material was deposited. So why do these "dirt" patches have matching characteristics of a horizontal formation? Good question. Typical fluid flow would have a meandering effect and also would tend to form "channels". However, the inferred prior post "saturation" clues indicate that this "dirt" was deposited and "guided" by internal structures to the dam - i.e. Twin columns, centered on toe axis of dam, core settlement longitudinal cracking (horizontal seams), plus ?

Why are these dirt patches significant? It proves that the dam is able to transport "vegetative growth" rich material into "patches" that have a "horizontal" nature. Why are these dirt patches symmetrically located & centered over the toe axis of the dam? The "settlement" that caused the original core horizontal cracks had a fulcrum point of the 1964 "hump" layer emplaced at the center toe axis of the dam. The core developed longitudinal cracks due to faster "settlement" on the adjacent sides of the bottom hump. This is called "differential settlement". The dam balanced its "settlement" compaction/consolidation and the upstream Transition zone did its job in sealing these original horizontal core cracks.

So what happened to these "dirt" patches? Over time, rains washed and eroded the "fines" away since the original "supply" of the "fines" ceased (i.e. the "saturated flow carrying the 'fines' was sealed in the core).

Some of these "fines" have been consolidated into the sands of the Zone 3 fill in both of these "dirt" patch areas. You can see this today as these areas are the two "Clean surface" areas on the dam. Outside of these "Clean Surface" areas, between in the center, and to the right you will see the normal gradual erosion streaks that the Zone 3 surface has endured from weathering. So this provides evidence for (1) the Clean Surface areas, (2) the center and right normal gradual erosion streaks, and (3) the disappearance of the saturated supply flow of soil type material (4) why there's no intense greening in these two areas today.

So what's up with the left abutment "Erosion channels and the Green Wet Area"?… Clues and evidence to come.

Clean Surface regions where original dirt patches have been washed & fines have consolidated into sands. Mild erosion streaking from non-augmented fines incorporated into Zone 3 sands.