Is the above a quote from somewhere or your own understanding? It sounds Very Bad and also realistic.
BTW on a local news link today the reportergal said 188,000 evacuated. I’ve seen a few numbers, I don’t know.
Natomas flood
for stories about a 100,000+ population in just one about-to-be-totalled Sacramento floodplain area. I like this 2014 op-ed:
http://www.sacbee.com/opinion/op-ed/article2604482.html
And the top of the emergency spillway weir is at the 901 foot level, not 909.