The comment you're replying to is about fresh water. Which becomes non-fresh when it mixes into seawater or waste or pollution. No need to leave the Earth.
Admittedly, it's probably better to talk about the cycle, since non-freshwater will be automatically converted back to freshwater via solar energy. But the rate can be slowed—eg, dump a bunch of toxic stuff in one place, it'll drain to a river, now everything from that point and downstream is no longer freshwater. Or pump up enough groundwater. Or inject toxic crap down where the groundwater lives.
We're quite good at reducing the total amount of freshwater available.
The comment you're replying to is about fresh water. Which becomes non-fresh when it mixes into seawater or waste or pollution. No need to leave the Earth.
Admittedly, it's probably better to talk about the cycle, since non-freshwater will be automatically converted back to freshwater via solar energy. But the rate can be slowed—eg, dump a bunch of toxic stuff in one place, it'll drain to a river, now everything from that point and downstream is no longer freshwater. Or pump up enough groundwater. Or inject toxic crap down where the groundwater lives.
We're quite good at reducing the total amount of freshwater available.