You want to quit throwing away plastic bottles, don’t you? Which means drinking tap water. I want to help, so I got a tour of Nashville’s Omohundro Water Treatment Plant from Scott Potter, director of Metro Water Services.
Situated right on the Cumberland River, the plant has great real estate, and is itself a work of art, with a spot on the National Register of Historic Places.
Some of the original workings are still in use, including a monstrous 1873 valve that pumps water from the river and into pools.
Once in those pools, the water gets a chemical shot designed to make all the bits of grit and algae clump together. In late summer the water is naturally so much clearer coming out of the Cumberland that it’s hard to get the clumping action to start.
(In warm weather, algae can grow in the river, and, if it weren’t addressed, would cause the water to taste funny. Metro Water Services adds carbon to prevent this problem.)
The water settles a while and flows into another pool, where honeycomb-shaped inserts cause the water to flow in a very straight line, which forces more particles to settle out.
At this point in the process, Potter says, “the water almost meets regulations--it needs one more step.” A sparkling result comes from guiding the water through filters modeled on the Roman baths at Bath.
Each filter contains varying grades of sand, and when it reaches the last bottom of the filter, you’ve got beverage-quality water.
That’s the process in a nutshell, and there’s lots more detail available at the Metro water website: including a water quality report and more detail about the treatment process.