Credit: Illustration by Slug Signorino

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Public service announcements admonish us to not “waste water,” with suggestions about five-minute showers, low-flow shower heads, fancy Euro-style toilets, turning off the tap when you brush your teeth, etc. I can understand this if you live in dry areas such as Reno or Vegas. But what if you live next to a big honking body of water like the Great Lakes or the Atlantic Ocean? I currently live in Halifax, which has the ocean, lots of lakes, and more than enough precipitation, and I still hear this stuff. As I understand it, if I take a shower for 25 minutes instead of five, the extra 20 minutes’ worth of water goes down the drain, into our filtration system, and eventually into the harbor. Some of it then evaporates and falls as rain, and the process starts over. How is water being wasted? Or is it just energy for pumping and filtering that’s being wasted? —Bob from Halifax

I used to think the same thing, Bob. However, I got over it. Let me lay out the facts and soon you will too.

1. Nothing against Halifax, but the fact that it’s next to an ocean doesn’t mean doodly. The ocean is salty. New York and Los Angeles are also next to oceans, but they still had to build vast aqueducts to haul in fresh water. Both systems are marvels of civil engineering and cost relatively little to operate—gravity does much of the work. Nonetheless, notwithstanding the drier climate in L.A., nobody in either city quarrels seriously with the logic behind don’t-waste-water campaigns: we didn’t spend zillions to transport this stuff hundreds of miles so mopes could, and I say this without excuse, piss it away.

2. The purer case, in water as in so many things, is offered by Chicago. The city is located next to one of the Great Lakes, which collectively account for 84 percent of America’s surface fresh water and 21 percent of the world’s. No great feat of engineering was required to obtain drinking water in Chicago; in the city’s early days, you could just walk out to the shore and drop in a pail. The engineering challenge in Chicago was sewage disposal, since the thing about living by a lake is that while it’s easy to get water out, it’s just as easy to dump crap back in.

Chicago solved this problem by taking advantage of the fact that it was purposely built near the divide separating the Great Lakes from the Mississippi basin. Demonstrating the low cunning for which it was even then notorious, Chicago surreptitiously inaugurated a system whereby it got its water out of the Great Lakes and dumped its slop into the Mississippi. (This is less gross than it used to be, since the stuff goes through sewage treatment now.) Some pumping is required, but as with the coastal aqueducts, it runs largely on gravity.

3. My point in telling you all this is that if there’s one inhabited place on earth that theoretically doesn’t need to worry about wasting water, Chicago is it. Evidently local bureaucrats felt the same way: to this day the majority of the city’s homeowners don’t have water meters, instead paying a flat fee, presumably to cover the upkeep on the pipes. The city is now installing meters at the leisurely pace of 20,000 per year, in part because its ticked-off neighbors got the courts to limit how much of Lake Michigan’s water it could hog for itself, and officials have now belatedly recognized the wisdom of elementary conservation measures. Still, setting aside meddlesome judges and looking at the big picture, could we not argue that due to Chicago’s unique circumstances, water really can’t be wasted there in anything but a trivial sense?

4. The answer is no. While the water situation near the Great Lakes isn’t urgent at the moment, out in the hinterland it sucks. The central U.S. is experiencing its worst drought since the 1950s. All of the past 11 years (2001-2011) rank among the 13 warmest years on record. The rains will surely return eventually, but with global warming looking increasingly real, water shortages are likely to be more frequent and severe. Groundwater aquifers and rivers are already being drained dry; the Great Lakes are the only good-sized rain barrel we have left. If the drought keeps up, desperate farmers all over the midwest will be asking to tap in.

The states and provinces bordering the lakes have signed a series of pacts agreeing to hold fast against the parched masses. But currently 95 percent of Illinois and 87 percent of Indiana are in severe drought, and what governor is going to let his own state turn into a dust bowl? So while conserving water right now may not seem all that vital, consider it practice for the day when it is. —Cecil Adams

Have something you need to get straight? Take it up with Cecil at