[21twelve]

I was reading where some auxiliary spillways have “fuse plugs” - sounds sort of like a self-destruct mechanism that will cause the spillway to fail so the main dam won't . (Like a fuse in your electrical panel protects the wiring inside the walls.) I looked around on the Oroville dam, and I didn't see anything like that mentioned.

Obviously with the auxiliary spillway being much lower than the top of the dam, it would also prevent a build-up of pressure on the dam just with the water overflowing it.

At the same meeting I mentioned the “emergency” spillway, and another person (also an engineer that works with dams) quickly corrected me and said “We use the term auxiliary spillway.”

I'm sure they have their reasons for the nomenclature - but in this case, seeing as it is the first time since it was built in 1968 that water has gone over the top, this spillway could be properly called an “emergency spillway”!)

[Ray76]

The auxiliary spillway seems to been a perfunctory effort. It will only be used during a high water event, the very worst time to be pouring water on bare earth (as if there is a good time). They could have at least hardened the area out to the crest of the hill.