‘literally life and death’ is exactly what I mean.
And it doesn’t require being on foot for it to be so. Las Vegas could literally not be more than a tiny town of desert rats without the water rights on the Colorado they have, same with Phoenix.
Instead they’re huge bustling metropolises.
Even with the issues going on in Europe, crops may die, farmers may go bankrupt - but no one will be literally without water and die from it, or even have to resort to overland tanking.
According to this random PDF from one of the Universities there, the typical household has decreased water usage down to 222 gallons a day. Which is quite low compared to the average in the US, no question.
The current Las Vegas metro population (not counting visitors) is 2.2 million people.
So that’s roughly half a billion gallons of water a day, or 178 billion gallons of water a year. Just for residential, not counting businesses, which typically are much larger water users.
Las Vegas typically gets a bit under 5 inches of precipitation a year.
5 inches of water on an acre of land is equal to 135770 gallons (an ‘acre inch’ x 5).
So to support the current residences in Las Vegas off precipitation alone, they would need to capture 100% of all rain over an area of approximately 1.2 million acres, or 1875 square miles.
Again, that isn’t counting commercial use at all.
Damming up the river which is the final terminus of a watershed estimated at 246,000 square miles (aka the Colorado) makes this a drop in the bucket.
Constructing something equivalent independently?
Not so easy.
And Las Vegas doesn’t have geology amenable to making due with some local damming. Red Rocks is quite pretty and would make a dent, but isn’t big enough.
And it doesn’t require being on foot for it to be so. Las Vegas could literally not be more than a tiny town of desert rats without the water rights on the Colorado they have, same with Phoenix.
Instead they’re huge bustling metropolises.
Even with the issues going on in Europe, crops may die, farmers may go bankrupt - but no one will be literally without water and die from it, or even have to resort to overland tanking.