Something you all probably don’t know: I lived in Marysville/YC for many moons.
I have been a part of that community during one major flood (1980s), heard tales of the earlier flood (1950s), and witnessed many near breaches of the levees in other years. It has permanently affected the way my wife and I live our life. We intentionally didn’t buy homes near the San Luis Rey River and always keep our gas tanks over half full. Live under threat of flood and you’ll know why.
In my opinion the only reason they haven’t seen more flooding on the scale of what was described in the article is increases in flood controls – the levee system has been greatly increased and many dams were built to contain runoff to a large degree. SoCal folks don’t even talk about Oroville Dam, but that is a magnificent creation. Shasta and Oroville Dams do an enormous amount to protect everything downstream including Sac and bay areas.
The threat of flood is unlike that of tornado or earthquake…those two events are over very shortly after the residents even knew they were coming. Floods on the other hand build slowly over a period of time. People lose sleep, worry about their family, and can barely function while the waters rise. This can go on for days or weeks, depending on the weather.