Microbiology: The Key To Wastewater Treatment

By Bulbul Ahmed, Andrew Newbold, and Rich Schici

The biological treatment of wastewater relies mainly on a consortium of heterotrophic and autotrophic bacteria. The fecal bacteria that are constantly introduced into the collection system are not the optimal bacteria for degrading the contaminants present in wastewaters. The soil bacteria that are introduced through inflow and infiltration are more effective at degrading the wastes and can contribute to stabilizing the downstream wastewater treatment process; however, the flux of these organisms into the sewer system is not enough to contribute to significant degradation in the sewer system under normal conditions. Collection system bioaugmentation aims to introduce high concentrations of specific soil bacteria into the outer reaches of the sewer system and amplify the beneficial effects of soil bacteria in the collection system. The downstream impact of this treatment serves to improve the condition of the collection system by reducing odor and degrading fats, oils, grease (FOG), as well as reducing organic loadings to waste water treatment plants (WWTPs) and increasing the efficiency and effectiveness of the wastewater treatment process.