I took my environmental politics class on a field trip to the wastewater treatment plant today in conjunction with learning about the Clean Water Act. When I was in college I spent one summer cutting weeds around the settling ponds of my hometown’s treatment plant, which the guys who worked there liked to call the shit factory.
That was circa 1984, just over a decade after the CWA. The basic processes today are the same, but there’s been substantial upgrading, and it’s really a pretty interesting process for anyone with a modicum of interest in science and technology.
One other interesting change came not from the CWA, but was driven largely (not solely) by 9/11, which is the on-going shift from using liquid chlorine as the final sanitizing stage to using UV lighting. Our town only has 20,000 people, and it previously had six 2-ton tanks of liquid chlorine. Holy WWI Battlefields, Batman! Imagine the number for a even a moderately sized city. An accident or incident waiting to happen. But UV lighting is not only much safer, it’s much cheaper. Our town installed UV about 4-5 years ago, and despite the upfront costs it has already paid for itself. You have to love a win-win like that.