Environmental Science Blog

A couple weeks ago, I was in the L.A. area, so I visited the Environmental Engineering Department at USC. It was a very worthwhile visit. I got to see the beautiful campus, and got to see what the school had to offer. But most importantly, I got to see one of the Environmental Engineering labs their. I took a tour of the water treatment lab, and there were so many different machines and tools that had very specific complex jobs. This experience made me recognize the importance of water treatment.

Clean water that comes from water treatment supplies the world with many uses including drinking water. Water needs to be treated properly to prevent the spread of disease. According to the CDC, some examples of waterborne germs are Cryptosporidium, E. coli, Hepatitis A, Giardia intestinalis, and other pathogens. The process of water treatment include four steps: coagulation/flocculation, sedimentation, filtration, and disinfection. Coagulation and flocculation add chemicals with a positive charge to the water so it can combine with the negative charged dirt. This creates “floc”, or larger particles made up of the positive charged chemicals and the negative charged dirt. Then, sedimentation is when the larger heavier floc settles at the bottom because of its weight. After that, filtration puts the clear water through filters to remove extra waste. Finally, during disinfection, a disinfectant like chlorine is introduced to kill all remaining bacteria and viruses. This whole process is important to make sure that the water we drink is safe.