Science

What does a water treatment plant do?

You probably know about water treatment plants. You may have driven or walked past one in your home town. But have you ever wondered what it does? What does a water treatment plant take out of the water before it gets to the tap in your home? When it comes to water for drinking, it’s what’s not in it that’s important.

The sources of our drinking water in Utah are rivers and reservoirs — natural bodies of water, habitats for fish, birds, mammals, insects and bacteria. They’re also receptacles of debris after storms, and run-off from farms and ranches. And, unfortunately, from industrial processes, as well. A water treatment plant has the job of removing everything we don’t want in our drinking water.

How a drinking water treatment plant works

Water has always been indispensable. We drink it, wash with it, give it to our animals, plants and garden, and use increasing amounts in a range of industries. A water treatment plant puts natural processes to work to remove harmful or unhealthy materials to make water safe to use and drink. Water treatment plants also treat wastewater — the water that goes down the drains, so that it can be reused or returned to the natural water cycle, without harming the environment.

Primary treatment stage

Most water treatment plants have two stages: primary and secondary. The primary stage removes large solid objects from the water. A screen keeps large floating objects from getting into the water supply: logs and sticks, rags, garbage or other debris that can be floating or suspended in the water. From there, the untreated water flows into a large tank or chamber where grit, sand and other solids still suspended in […]