
There are not enough tanker trucks in the US to be meaningful. That ignores the practical problem of cleaning them out.

There are not enough oil pipelines in the US to be meaningful. That ignores the practical problem of cleaning them out.

With all oil and gas transport means diverted to shipping water to CA, how would those DU-folk who actually work get to work? After a few days or as much as a couple of weeks, their cars' tanks would be dry, buses' tanks would be dry, and the whole working country would be high and dry.
California's climate, for centuries or millennia, has oscillated from wet years to dry years to ... . Staring in the 1970s, the Enviros and the Dems, directly and through courts, have all but shut down new water storage projects, obstructed expansion of existing projects, and forced the waste of stored water on the delta smelt.