Host Hank Green explains what happens to human waste after it’s flushed down the toilet in a recent episode of SciShow (see previously). Some waste is sent directly to a septic tank while the rest is fed into sophisticated processing plants where it is broken down, cleaned, sanitized, and the usable water is filtered back into use. Green also describes the history of waste management and how it’s still a problem in developing countries.
Humans have always peed and pooped, but where it goes after we’ve done our business has changed a lot. In fact: The water you just drank may well have been a part of someone’s urine just weeks ago! SciShow explains!