Water Treatment

Not all water is safe to drink or to take a bath in. Some of it needs to be cleaned or purified before we can use or drink it. This is done in three basic steps:

  1. Water first flows through a basin which has chemicals in it . The bacteria , mud and other dirty substances that are in the water stick to these chemicals and move down to the bottom of the basin.
  2. Water then goes through a filter made up of sand and gravel . Other particles are filtered out.
  3. In the last phase chlorine is added to the water. It kills the bacteria that somehow get through.
Dirty, used water is carried away through sewage systems . It often smells bad and has a lot of bacteria in it. Most cities have treatment plants that turn used water into clean water that can be used to irrigate fields.

Water treatment plant in Germany
Image: https://www.flickr.com/photos/gtzecosan/12359229313
Source: Sustainable Sanitation Alliance