The goal isn't to "stop them from using up the water", it's to charge them the true price of providing that water, and charging a bit extra so we can subsidize the price of water for the poor.
I think this premise is sufficient in any scenario where there are disparities in the distribution of a plentiful resource, as is the case in countries with privatized water.
However, when the resource is no longer plentiful, it is unwise to try the "let the market fix it" route (always a popular one on HN), because the resource in question can be consumed much faster than the systems you are describing can combat it (or can even be gotten off the ground.)
>However, when the resource is no longer plentiful
My previous comment mentioned acquisition methods up to and including desalination, which would make the resource virtually unlimited. If the rich want to water their huge mansion grounds and are willing to pay for a desalination plant to do it, why stop them? If they're willing to do that, and we can take a portion of that money to subsidize water supply for the poor, all the better.
I'm genuinely curious - what are the economics like for desalination plants? I feel like we'd see a lot more of them if they were viable, but maybe we're just horrible at planning and fixing things.
There are plenty of environmental issues associated with desalination, it's not a get out of jail free card. Obviously energy use (and even if that energy comes from solar it's not completely free of consequences) but also the brine from desalination can cause significant local salinity issues which damages aquatic life.
All of those issues can be addressed with money, which is presumably not an issue because the original premise of this thread is that the rich will gladly pay the steep costs.
No. The idea is to charge them enough for their water that you can afford sources that are expensive but won't run out (e.g., desalination) to provide it.
