[jjav]

> Water districts are just an artificial administrative construct within a state, though.

This is not at all true. Different districts get their water from different sources, these are no connected. My town gets water from groundwater here and if that runs low (as it is now), that's it for the water source. A nearby town has a small reservoir, that's their water source. A smaller town not too far basically ran out during the past drought. And so on. These are physically separate systems. Most of these are running low, a few are past an emergency point.