In California, much of the central valley would flood in wet years but for the extensive levee system. However, just like with maintenance at Oroville Dam, many levees are poorly maintained and are prone to fail at their weakest link. Here we have one attempting to give way, of course in the middle of the night.
Just this Saturday, Mrs. CW and I met friends in Manteca at the point where Highway 120 breaks off from 99 and goes east, or to the right, right at the top of this map. Not far at all from where this is happening.
No doubt, there will be additional levee issues over the next few days.
A bit closer to me is the Cosumnes River, which has no dams on it so it is a totally wild, uncontrolled stream.
Right now, as I type, it is just inches below flood stage at 12 feet, and expected to crest (according to the very calming female voice on the radio) at about 15 feet (at Michigan Bar). That will certainly flood the Wilton area to the north and west of me, but everyone who lives there expects this and all but the super stupid should be well prepared. Other areas may flood depending on how well the levees hold. There has been some damage to the local levees on this river, even before this current series of storms.
Should be an interesting drive in to work tomorrow. The specific location where I live is safe, so fortunately no levee break or river flood will get me, but that isn't so for many people.