If the water erodes around the side of the auxiliary spillway, the whole lake could pour through there.
I own a lake, it’s small, only 14 acres at 55’ deep, but I have a levy almost 300’ long with a primary and emergency spillway.
What cracks me up is the state of Indiana crawls up my butt every two years with a magnifying glass inspecting that levy and the emergency overflow trench cut through the rock. Even a small tree growing up in it, or an exposed piece of dirt without a thick layer of sod on it, and I get red flagged and fined.
Watching this unfold has been an eyeopener for me simply because how California allows a levy that has such a huge impact to be so shoddily maintained is beyond me. Had the old fart I have to deal with bi-annually on my inspections been out there there wouldn’t have been enough red flags and tape in the whole county for him to use on it.
I guess when it’s state controlled and money is involved they can tell old farts like him to shut up and go fine taxpayers on their private property and leave the state controlled levies to the “experts”.