Department Environmental Microbiology

Microbial stability of greywater

The possibility of microbial and pathogen growth in reclaimed and treated grey water raises a safety concern for consumers. As part of the Blue Diversion AUTARKY toilet (BDT) the goal of this project is two-fold:

(1) to examine microbial and pathogen growth potential in treated toilet wastewater recycled for hand washing and personal cleansing, and

(2) to investigate key factors governing the growth potential.

Culture and molecular based methods in coupling with flow cytometry are used to measure microbial and pathogen growth under the influence of nutrients (e.g., fractions of oganic carbon, nitrogen, phosphorus), indigenous microorganisms, and residual disinfectant (e.g., chlorine). Reclaimed and treated grey water samples from different wastewater treatment systems will also be included to have a better understanding in other contexts besides the Blue Diversion AUTARKY toilet. Findings will shed the light to maintain microbial stability in reclaimed and treated grey water to reach safe level for water recycling.

Picture of Blue Diversion prototype toilets installed in an existing structure