We can't predict exactly what will happen during a given year in the future. Like, for example, 2050. Will I be alive then? Don't know. If I am, I'll be 82. Don't know where I'll be living, who my friends will be, what kind of clothes will be in fashion, whether or not I'll have full control of my bodily functions.
I do know that I'll probably use a lot less water than I do now. The Natural Resources Defense Council just released a study estimating that one third of all counties in the United States will be at "high or extreme risk" of water shortages and drought in the year 2050. Thanks to climate change, the report notes.
The map of affected counties looks like this:
The counties colored red are the ones that face the biggest risk of running out of water. More information on the NRDC report is here and here.
The forecasts in the report assume that demand for water (by homes, businesses, agriculture) continues to rise at current rates through 2050. I think it's safe to say that, at some point, the demand will be forced down, as useless uses of water are phased out. Like golf courses and lawns. The cause will be not only climate change but also the permanent, never-ending economic implosion enforced by energy descent. In a collapsing economy and super-heating world, we won't be able to afford water-guzzling luxuries like desert putting greens. Or Las Vegas casinos surrounded by giant moats.
Yet we continue throwing water away none the less, despite absolutely certain evidence of the coming shortages. Here's a scene from the courtyard outside my workplace:
A fountain vomits water into the open air on a 91 degree Albuquerque day in July. I might be missing something, but this use of water strikes me as monumentally dumb. The rate at which that water evaporates on a hot summer day is, from what I understand, rather considerable. I'm not terribly knowledgeable on Albuquerque's hydrologic cycle, but it seems like much of the evaporated water will end up someplace other than New Mexico. The water that disappears into the air, as seen in the diagram below, eventually travels far from the Gushing Monument of Dumb, lurking just outside my office.
Maybe I'll check with the authorities in charge of that fountain, to ask them how much water it loses per day to evaporation. Maybe I'll also ask whether such water use is a good idea. Just to see the reaction I get. I expect that any proposal to get rid of the fountain, in favor of a more water friendly xeriscape decoration, will not get a friendly reception. It's a little like dealing with a lung cancer patient who still smokes three packs a day.
The future will always be unknown. But not completely unknowable. Pictures from the present can tell us a lot. Sooner or later, we'll have to start paying attention.