Water and wastewater treatment is generally performed by physical, chemical or biological methods.  All treatment processes use some combination of these three methods.  Physical and chemical treatment are fairly straightforward, they use gravity settling, filtration and chemical reactions to remove impurities from the liquid to be treated.

Biological treatment is somewhat more versatile, from a technical point of view.  Because treatment can be provided by a variety of processes and a wide range of microorganisms, the biological nature of the process should be reviewed.  Our Interactive Microscopes give you a good look at some of the microorganisms that purify wastewater.  Each microorganism shown in our interactive microscopes has its common name and genus displayed for your information.

Organisms Found in Wastewater