In case you were wondering if Lake Mead is drying up this rapidly due to numbers of people, well, yes, but indirectly. Christopher Ingraham on The Why Axis says the immediate culprit is farming:
Conceptually the west’s water problem is a simple one: humans are draining the Colorado River faster than it can replenish itself via rain and snowpack, a problem compounded by the ongoing drought. But this is fundamentally not a problem of cities being too big, or populations being too high, or families doing too much laundry. Entsminger’s testimony points to the real culprit: desert farms.
“Around 80 percent of Colorado River water is used for agriculture and 80 percent of that 80 percent is used for forage crops like alfalfa,” he said. Stop and sit with that one for a minute. Eight out of every ten gallons that flows down the Colorado gets diverted to farms and ranches. And most of that gets turned into alfalfa for use not by humans, but by cattle.
Western farmers, in other words, are pumping precious water hundreds of miles around the desert in order to grow plants and animals that cannot otherwise survive there — especially during a multi-decade drought. It’s profoundly wasteful, a practice untethered from a reality that has finally caught up with it.
He also seems unduly optimistic about humanity’s wisdom:
The optimistic case for the southwest is that these dire conditions force a rethinking of how agriculture is practiced in the region, leading to water savings that put the river on a more sustainable footing. A couple winters of record snowpacks could go a long way toward replenishing water levels on Lake Mead.
Me? Between overpopulation, chronic narcissism, and general need to make a living, I don’t think we’ll learn a damn thing.
And here’s a nice graph of Ingraham’s.
