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http://sacramento.cbslocal.com/2017/03/23/temporary-fix-for-oroville-dam-spillway-could-involve-making-water-jump-gap/

Temporary Fix For Oroville Dam Spillway Could Involve Making Water Jump Gap
By Drew Bollea

March 23, 2017 11:10 PM

SACRAMENTO (CBS13) — Officials with the Department of Water Resources are mulling over temporary and permanent solutions to the Oroville Dam Spillway crisis. They were presented with the findings from a group of engineering experts who analyzed the problems and potential fixes to the beaten and battered spillway.

“I think it’s one of the most urgent infrastructure things you could imagine,” said Jay Lund, a civil engineering professor at UC Davis.

Lund read over the panel’s report, which outlines issue with the spillway and suggested solutions.

“They point out that there is potential for additional things to go wrong on the remaining portion of that spillway,” said Lund.

“It’s a minor miracle that it’s working pretty well given its state,” he continued.

The panel identified faulty piping, deteriorated concrete, and cracks that may have weakened the spillway foundation. Now they’re proposing some unique solutions.

One temporary recommendation is building an angled flip just above the collapse site. If water needs to be released from the lake down the spillway, the flip would launch the water away from the hole, preventing further erosion.

“I think it makes a lot of sense,” said Lund.

Lund says it’s a typical practice at other dams, but this would likely be the first attempt to jump a hole.

“They’re not holding back,” he continued.

A spokesperson for the Department of Water Resources says “We are in the process of analyzing alternative approaches, both temporary and permanent”

Experts are suggesting a two-phase solution. A fix through this year, with a complete rebuild of the main spillway in the future.

“It’s just a matter of how much time it takes and to what expense you want to go,” said Lund.

[mad_as_he$$]

I am speechless. Where do they find these idiots?

[EarthResearcher333]

I suspect* that there may not NOT be any hard Amphibolite to anchor to with a "flip" at the plunge pool. Did you see the post on the core sample? What a complex geological strata challenge. The Amphibolite was a seam sandwiched between what looked to be "less fresh" rock. This core sample seemed to be somewhere in-between the ES and MS in the upper spillway elevation.

(note: the "flip" buckets at the end of the original spillway looked to have plenty of hard Amphibolite to anchor to)

*The end of the broken spillway revealed a heavy layer of weathered rock.