Even if you think your shit doesn’t stink, consider that at one point or another your thirst has probably been quenched by water from a septic tank.
Illustration by Ben Montero
Earlier this year, US intelligence agencies published a report concerning the growing likelihood that nations will soon wage war over the world’s dwindling supply of fresh water. One possible solution to circumvent this looming crisis is to literally drink our pee and poo. Even if you think your shit doesn’t stink, consider that at one point or another your thirst has probably been quenched by water from a septic tank.
Since the 1950s, sewage has been recycled and purified into drinking water in many places throughout the world. The results have ranged from mass outbreaks of dysentery to crystal-clear, refreshing liquid that you’d never guess came out of someone’s anus.
Perth, Australia, is the latest municipality to test these questionable waters with what they’ve termed the Groundwater Replenishment Trial. Since November 2010, over 1,500 megaliters of the formerly brown stuff has been pumped underground to a containment system located far away from local drinking-water reservoirs. The plan is to let it sit here until the end of the year, and then Perthians will have to decide whether they’re thirsty enough to take a sip.
Nick Turner, manager of water-source planning for Water Corporation, told us sucking down a glass of shit is no big deal. “There’s no new water in the world; it’s all been going around for millions of years now,” he said. “There could be a molecule of Leonardo da Vinci’s wee in the water I’m drinking today.”
Changing the subject, we asked Nick to give us a step-by-step breakdown of how excrement stew is transformed into potable, life-giving H2O.
Preliminary Treatment: Raw sewage is collected and passed through a series of screen traps to remove all of the random gunk that sticks to poop (“the rags and the rubbers,” as Nick put it).
Primary Treatment: The sifted shit is then pumped into a container where it stays until gravity separates any remaining grit and it is deemed safe for the purification machinery.
Secondary Treatment: After all solids have been removed, the liquid is transferred to an aerated tank filled with microorganisms whose favorite foods are feces, drugs, and hormones.
Advanced Water Treatment: At this point you’ve got something that you definitely wouldn’t drink but might swim in if you were on MDMA. The next step is to squeeze the mess through a series of membrane filters that remove anything wider than 1/300th of a human hair, and the water is then zapped with ultraviolet rays, which according to Nick is “just an insurance policy.”
Injection: What was once a murky mess of smells is now transparent and technically safe to drink (it’s even a bit less salty than tap water), but we’re not quite done yet. The end result is injected 656 feet underground into the Leederville Aquifer, where it’s diluted in 120,000 gigaliters of groundwater.
Monitoring: Finally, the resulting water is continually examined by people who have very boring but important jobs. Over 40,000 water samples have been taken throughout the trial, and everyone says it’s good to go. Drink up!