Apparently the plan for the Oroville Dam main Spillway is to continue using it to dump excess water out of the reservoir, while observing what happens to the rest of the lower portion of the spillway. From the looks of the pictures, there is little if any steel reinforcing in the spillway floor, and varying thickness of concrete. Continued discharge through the spillway will likely destroy most of the structure below the original hole, and wash away portions of surrounding terrain. The big question in my mind is what the hell happened when they built this thing. No reinforcing? Uneven concrete floor thickness? No pressure grouting under the floor slab? I think DWR has some explaining to do. There may be little or no risk to life and property nearby, but look at all the taxpayer dollars wasted! (To make this railroad-related, anyone remember the deadly train collision at a tunnel portal during the dam construction?)