We’ve probably all taken a moment or two to contemplate – “Where does it go?” and “Where does it come from?” after we have flushed the toilet and seen it refill. Imagine how most of us would react knowing that the answer was: the same place.
Most adults would probably rather not think about their dirty water—that is flushed or rinsed down the drain—and clean water being virtually one in the same. Moreover, indoor plumbing is taken for granted (well, until a leak occurs or a pipe bursts). Yours truly experienced this firsthand during the recent frigid weather we have had here on the East Coast.
But in my mind, a process of wastewater removal and purification does deserve attention and appreciation! This process goes back to ancient Rome when they built the first major public sewer, the Cloaca Maxima (“The Great Drain”). Sewers are critical to health and sanitation. Moreover, the process we employ today still uses at least two key elements as those of centuries ago: an elaborate network of pipes and the power of gravity.
So how does it work? When the “used” water flows out of your house through a small pipe it enters another, larger pipe connected to other houses on your block, flowing on to another larger network of pipes. Eventually it empties into the municipal sewer and flows to a treatment facility, previously called wastewater treatment plants but now are more accurately referred to as Water Resource Recovery Facilities. Many facilities even generate energy from biosolids – water and energy are two important resources!
During the first stage of treatment—the primary clarification tank—suspended solids are separated and removed. Next comes a secondary clarification tank, removing more foreign matter. By the time the water goes to phase three, about 90 percent of contaminants are gone. What remains now is the final treatment, which includes intense filtering and addition of purifying chemicals. The result is purified water and is released back into local waterways where it’s used again for any number of purposes, such as supplying drinking water, irrigating crops, and sustaining aquatic life.
My explanation, of course is quite simplified. And in terms of technology, science and water quality; treatment is light-years apart from the Roman aqueducts. Still, given the issues of aging infrastructure, we all need to do our part to keep items that can cause clogs as well as other contaminants out of our pipes.
So, be responsible the next time you’re about to flush or drain, considering where that water is going, and that it might end up right back where it started!