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>>I believe that is exactly correct. The issue has apparently been the subject of heated debate on multiple occasions in the past. <<

Sorry to pepper you with questions...

You seem very well connected & knowledgable in terms that are unique to this situation.

I believe you are familiar with Scott Cahill’s analysis. Scott’s articles and podcast interviews have provided specific engineering issues the dam is facing at this moment.

Correct if you have a different view:

(1) One of the issues Scott described was the existence of the fractured rock. The swift erosion of this fractured rock revealed its depth (how deep it exists) from the overspill flow. Survey elevation of the before and after at this location reveals that this fractured rock depth is lower than the foundation area of the main spillway.

(2) Another issue brought up was “migrating water” under the main spillway slabs. Scott stated that the “jets” of water on the spillway sidewalls reveals just how much of this waterflow exists underneath. He said a properly maintained system would not have such a vigorous flow - that this flow may cause an erosion risk & thus potential failure stresses on the concrete slabs (in time).

(3) Scott also discussed Emergency Spillway: wherein the subject of this spillway also rested upon this fractured rock. (btw: the original blueprints of the ES “encasement” is an aggregate filled concrete shell. The depth of the grout footing was not clearly stated).

This gets to the rock & quick set concrete surface repairs to the Emergency Spillway (fixing the recent erosion gashes & trying to establish a better “rough version of a controlled, but ugly laminar flow”)... Have you heard about the news chopper video footage (Fox10) of “car sized” air bubbles coming up on the water side of the ES? These huge bubbles were coming from 2 locations. This would infer that notable amounts of water (bubble equivalency translation) was penetrating somewhere. At the time of the footage, this was a few days after the overspill. Seems quite a bit of time for any trapped air in the dry sediment to suddenly come out that late.

IF this penetrating water was getting into the foundation of the ES, has there been any action to identify this? (Scott stated that he was not sure if the dam will survive (in time) and that a “V” breach is his greatest concern. He was speaking with respect to the areas resting on the fractured rock - which to me identifies it as the Emergency Spillway. Elevation erosion of the crevasse hole bottom yields a known (easiest to achieve by proven erosion - if the reinforcements are scoured again) low point of the “V”. If you take the 901ft upper part of the “V” then the low point of the “V” comes to near 100ft.

Scott did not mention anything about news on the penetrating water issue. I would assume he would have something to say about this issue potentially defeating the re-inforcements as this is a stability & undermining problem.