Okay. So let's do that. Let's let the price of water reflect its scarcity. Appropriate conservation measures will follow automatically without some central bureaucracy having to make uniform rules that are necessarily poor fits for individual preferences and circumstances.
> Let's let the price of water reflect its scarcity.
You say that like it's the easy solution. It'd have to be regulated on a federal level. Good luck getting that to pass, well, anywhere. With the way humans discount future consequences, and the amount of money companies can use to lobby or bribe politicians, it's going to be way too late when it'll become politically feasible to do in many places.
Because we'd have to rework the existing legislation that determines who has right to the water, & also the various legislation that expressly prohibits the reselling of water or the forming of water markets. We don't legislatively set the price, but we have to create the conditions for the market.
The market is very good at ignoring or hiding scarcity or other externalities until the damage is done. Nothing is "automatic" about it. The "free market" doesn't exist in a way that would allow the price to organically reflect water's actual scarcity.