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To: Ray76
Hi Ray76, the answers to your questions require starting way back at the original total flood control "concept" design. From this starting point, thereon followed a historical accounting of engineering testing, analysis, expert inputs & change process - forming long series of design decisions. These design decisions fall into "Engineering Judgement". Along the way, some interesting events occurred (very important "tradeoff decisions"). To get this understanding, a person has to walk back through all of the design archives & studies, and reconstruct the process, to see how some original design specifications were transitioned into "assumptions"** when non-solution space was encountered.

**Assumptions: Term to identify where unanticipated alternate solution options were chosen where the decision(s) had a sense of a political tradeoff. "Political" in the sense of a decision that did not have the "scrutiny" of the engineering processes of the prior decisions. Whether this was done because of schedule reasons, cost reasons, plain assumption, or "being overruled" is not stated (not stated fully in the archives), but is recognizable by experienced engineers familiar with large & complex projects were command decisions occur.

I will post more on some key decisions and their significant impact on the MS & ES final design.

2,588 posted on 03/21/2017 6:34:46 PM PDT by EarthResearcher333
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To: EarthResearcher333

Political solutions are a huge issue when government takes on tasks that have real-world consequences down the road. It happens a lot, but usually with less risk. And it generally seems to happen well after the errant politician(s) are out of office.

I’m with TVA - we are quite the quasi-government outfit. I see stuff that is generally jaw-dropping. Then again, with Obama’s war on coal, I have the whole electric power industry do some jaw-dropping things.


2,589 posted on 03/21/2017 7:19:20 PM PDT by meyer (The Constitution says what it says, and it doesn't say what it doesn't say.)
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To: Ray76; Grampa Dave; Jim 0216; WildHighlander57; meyer; Repeal The 17th; KC Burke; Oldexpat; ...
Politics of Engineering Judgement: How Failure is introduced…

Continuing from a discussion:... "When such entities encounter critical design issues, the dynamics of this "political sense of engineering" may result in consequential outcomes. THE MOST consequential outcome, for Oroville's Flood Control scheme, originated from a crisis from hydraulic fluid flow test studies. A huge problem forced a re-design of the original concept, that ultimately led to the design as it is today. From the series of events that followed, a decision tree may be traced that reveals a "political dynamic" in tradeoffs that occurred."...

= =

The information below reveals the evidence of "political forms of engineering decisions" that resulted in a flawed total spillway design (true specs/performance) & violated the norms of high standards of dam engineering safety assurance. By simply "deeming" the use of a Weir based Emergency Spillway as "infrequent" and exceeding estimates of 10,000 yr maximum usage conditions, a "rationale was justified" to allow a "political solution" to introduce a significant design flaw in engineering judgement. This dangerous "rationale" justification propagated into other evidence of lesser importance consideration factors including non-anchoring of the Weir, non-concern for damaging erosion, no consideration to construct armor protection of the hillside, make the Weir long enough as needed to meet a flow "number", etc. All justified due to an introduced "reasoned minimal use" of a long Emergency Spillway Weir [6]. LEFT OUT of this "rationale" was the imperative safety necessity of REDUNDANCY in case of failure. i.e. The Main Spillway became supercritical in that any failure to the Main Spillway structure HAD NO backup (no redundancy as ES had high risk - unproven/tested [5]- and validated to be flawed) & that could risk the entire dam.

These type of "rationale" justified decisions, that lack a full comprehensive engineering thoroughness, is what leads to grand failures (in the politics of engineering judgement).

The Original Oroville Dam Spillway was presented to the public where it had a design capable of handling standard condition floods up to 440,000 cfs and worst case floods up to 720,000 cfs (reservoir inflow). As presented, the public could be assured that the design could handle worst case conditions such as the 1861-1862 MegaFlood. To meet this criteria, the flood control spillway was originally designed for a total 620,000 cfs flow using a massive "delta" set of combined gate structures of a "main" and "emergency" headworks. See the Artist's concept painting [1]. IN this design, there is NO erodible hillside flow spillway [2].

Then a Crisis occurred in scale model testing of this design. "Fins", "Standing Waves", and "monster splashing" (up to 100+ ft re: model scale) were becoming too challenging to resolve [3][4]. Turbulence and Eddy swirls aggravated the challenge. The cost of the fixes, in the fix design construction, was becoming more extensive from deeper rock excavation and higher concrete volume requirements. In the summation of these mounting design challenges, the California Department of Water Resources stepped in and made a "command decision" to break the combined design into two separate structures[5]; A main spillway with a separate Emergency Spillway Weir (as it is today & Failed at 12,000+ cfs [6]).

+Image [1] Original Design proposed to the public for funding - a combined high capacity spillway - Artist's concept painting.

+Image [2] Original Spillway design with Combined Flood structure - 620,000 cfs total capacity (370,000 cfs main flow + 250,000 cfs emergency flow).

+Image [3] Original Spillway model testing reveals "Fins", "Standing Waves", and "monster splashing" (up to 100+ ft re: model scale) @ 620,000 cfs total capacity (370,000 cfs main flow + 250,000 cfs emergency flow).

+Image [4] 3rd round of "fixes" in model testing still reveals challenges @ 620,000 cfs total capacity (370,000 cfs main flow + 250,000 cfs emergency flow).

+Image [5] California Department of Water Resources steps in and makes a "command decision" ("political engineering") when faced with this design crisis challenge.

+Image [6] Failure is introduced from the "a political engineering decision" with flawed rationale/justification (excludes full scrutiny in engineering thoroughness).

Image [1] Original Design proposed to the public for funding - a combined high capacity spillway - Artist's concept painting.


Image [2] Original Spillway design with Combined Flood structure - 620,000 cfs total capacity (370,000 cfs main flow + 250,000 cfs emergency flow).


Image [3] Original Spillway model testing reveals "Fins", "Standing Waves", and "monster splashing" (up to 100+ ft re: model scale) @ 620,000 cfs total capacity (370,000 cfs main flow + 250,000 cfs emergency flow).


Image [4] 3rd round of "fixes" in model testing still reveals challenges @ 620,000 cfs total capacity (370,000 cfs main flow + 250,000 cfs emergency flow). Note the "hand control angle experimentation" of vanes by engineers.


Image [5] California Department of Water Resources steps in and makes a "command decision" ("political engineering") when faced with this design crisis challenge.


Image [6] Failure is introduced from the "a political engineering decision" with flawed rationale/justification (excludes full scrutiny in engineering thoroughness).



2,596 posted on 03/22/2017 9:29:46 PM PDT by EarthResearcher333
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