Also, they knew about the deteriorating conditions over time, but chose band-aids, instead of a fix. Completely replacing the spillway in and around the problem area would have cost a fraction of what we taxpayers are facing now.
It all boils down to money, and the priorities of the leftist-de-jour in charge of the state. Brown, and some before him, chose to fund a useless train to nowhere at a HUGE cost (not to mention welfare and protection for millions of ILLEGAL IMMIGRANTS), rather than take care of a crumbling infrastructure that affects millions of taxpaying Californians.
It makes one wonder what other significant structures in the state are in need of significant repairs or replacement.