Nothing 48 hours of drying and prep followed by 120,000 1/3 cubic yard helicopter delivered buckets of high-early ready mix concrete on top of 500 gabions of one foot diameter rip-rap couldn’t take care of in a heartbeat.
Only problem is that those buckets at one every 30 seconds would take one thousand hours to drop in place.
1/3 cu yd sounded way too low but after researching it is a reasonable estimate for a single-rotor at that elevation.
The Ca NG has a dozen pretty new CH-47f Chinooks with a max cargo of 24,000 pounds. They may not want to get them dirty though.
There’s been no work done on either spillway today. Lake has only been lowered 8 feet.