I'm not sure if this counts as "environmental," but David Zetland has a fun post on the economics of banning people from bringing water through airport security gates. His prediction? The ban will likely never been lifted. The original safety rationale may have faded, but the ban has produced whole terminals full of vested interests intent on keeping it in place:

The airport managers can save money by installing fewer fountains because people can buy water; the vendors can sell more water because there are fewer fountains (supply) and more people without water (demand); worst of all, the airport managers can charge more rent to vendors because they are selling more water. Who pays? The travellers!

This is an example of monopoly (airport manager) taking advantage of the customer—selling less water for more money. (The same thing has been happening in schools where school administrators have been abusing their monopoly to sell more water—and soda—to kids with few outside alternatives.) ...

Third, there's the warm water in the sinks in bathrooms. Although I am sure that this is meant to provide a better "customer experience," my devilish side says that warm water prevents "customers" from filling their own bottles. My environmentalist side says that we are wasting energy for very little gain in happiness.

That last bit's pretty amusing. I'm not totally sold on all this—seems like there are still plenty of water fountains at the (admittedly low number of) airports I've been to, though I guess it's not improbable that we'll start to see fewer and fewer.

(Flickr photo credit: Jack Spades)

--Bradford Plumer