This post from Tyler Cowen from Saturday illustrates some interesting features of our water use over the past 30 years. Evidently, our aggregate water use has not changed in 20 years:
The flat trend in consumption came even as the USA’s population grew and electricity production, the largest user of water, increased.
Of course, one of the cool things about hydro power is that you can reuse the same water over and over again, by pumping it back up to the top at night when it’s cheap to generate power to do so. That’s called pump storage. But I digress …
What amazes me is that this decrease has come notwithstanding the fact that water is one of the most illogically and inefficiently priced and used resources on the planet.
Tyler notes that 70 percent of water use is in agriculture, and at least in the US, a lot of water gets used in agriculture that may not be needed because of the lack of transferability between potential uses and the “use it or lose it” bureaucratic mentality that has overtaken the interpretation of historic water rights. In my ideal world, the historic water rights that farmers have would be a fully transferable and alienable property right. So if San Diego, for example, is willing to pay more for water than the value that the water represents to my crops, then I’m gonna sell. Such transactions can’t really happen now, so we get locked into inefficient and non-value-maximizing uses of water.
Put it another way: our water use has not gone up in 20 years. If we paid prices for water that reflected the true cost of its use, and if farmers could transfer their property rights over water to non-agricultural users, think how much less water we could be using than we did 20 years ago.
I also think Tyler’s point about nanotech desalinization is pretty cool. So in my lifetime I could have a Nalgene bottle with a filter that would turn salt water into fresh? Sweet! La vita e bella.