We haven't had any significant flooding in past El Niños. Of course, it will probably be different this round, but at least El Niños tend to align with Mediterranean weather instead of droughts and wildfires.
We also have one of the more advanced waterwork system in the US to support Central Valley agriculture, so a lot of the worst aspects can be somewhat managed.
It's bad that such dramatic climate change is happening, but we're definetly lucky to live in the West Coast because we won't face the brunt of some of the worst aspects of the El Niño comparatively and have the infrastructure to deal with it.
Sadly, the brunt of climate change will be felt by the poorer half of the world.
The costliest floods in state history were in the winter 1994-1995 which was a weak El Niño year.
True, but a lot of that was due to a lack of integrated water management (IWM) in California at the time, and led to significant reforms as well as infra expansion to prevent that from happening again.
The Lima Prieta Quake and the 1990s floods led to a lot of future proofing in Californian infra. The last major thing left is transmission weathering, which PGE and Sac are fighting over.
Also, most of our infra is state funded which gives us a lot of leeway.
Like I said before, it's bad that we're in this position and it's only going to get worse, but we're in one of the better places that can survive these kinds of shifts.