Thanks for the calculations.
0.00877m³ = 8.77l which is about as big as a 10l bucket. Not that big. That would be for the drinking water of 2.4 people. I imagine for the entire water consumption of 2.4 people, it would be way more.
For people living in the desert though, if this is low to no maintenance, it does seem possible. Buy once, use forever.
Goodness me, US politics is cancer. It's so depressing. I'm unsubbing.