We should hope not; Beale is not only home for the Air Force’s U-2 fleet, it also hosts an intelligence group that plays a key role in analyzing info collected by U-2, Global Hawk and Predator/Reaper missions around the world.
While the analysis role could be shifted to other intel groups (all part of the 480th Intelligence Wing at Langley AFB, VA), potential flooding would force relocation of U-2 operations—and not all of the logistics stockpiles, maintenance facilities and support equipment could be quickly moved. If the base flooded, some of those resources would be lost, and operations would be disrupted.
Langley experienced minor/moderate flooding during a Category I hurricane about 14 years ago. The base suffered $250 million in damage.
I’ve drive by Beale AFB. Fortunately, most of the important facilities there are located on higher ground, and PAVE PAWS radar installation is not under threat because that’s built up on a hill.