I do not disagree with any of your calculations. The Feather River starts in the Sierra Nevada & comes a long way with lots of watershed before it gets to Oroville Dam.
IF there is serious flooding, it will last more than ‘a few months’ & the entire rice crop & thousands of acres of alfalfa will be wiped out. The farms & ranches in the Sacramento Valley are BELOW sea level, depending on the levees to keep they dry. Dairy farms, horse operations, and other crops grown. The face horse California Chrome came from Yuba City area.
IF anyone here remembers the 1986 & 1996 floods into Marysville & Yuba City, they were pretty damaging—and the high water mark on buildings in Yuba City were over 10 feet above he ground. I saw that for myself, when I lived just east of Yuba City in Grass Valley.
Maybe this season will have an effect on the 2018 elections in Sacramento and get rid of some of the real dumb asses in the legislature.