By Jael Batty

Activated sludge is a mixture of microorganisms that come in contact with and digest biodegradable materials (food) from wastewater. Once most of the material is removed from the wastewater, microorganisms form floc and settle out as sludge. Some type of microorganism will always grow in the system. The organisms that will dominate will be the ones that are best suited to the environment.¹

Microorganisms that are natural to the wastewater environment play a vital role in the wastewater treatment process. Beneficial bacteria, protozoa, metazoa, algae, and fungi feed on organic material in wastewater, breaking it down. Bacteria clump together, or floc, forming masses that settle and separate from wastewater liquids. This settled mass is called sludge. This week, we’re going to talk specifically about wastewater bacteria. Read more about wastewater bacteria