Grantee Research Project Results

Assessment of Advanced Water Treatment Processes to Promote Safe, Stable Microbial Communities in Direct Potable Reuse Distribution Systems

EPA Grant Number: FP917829
Title: Assessment of Advanced Water Treatment Processes to Promote Safe, Stable Microbial Communities in Direct Potable Reuse Distribution Systems
Investigators: Miller, Scott Evan
Institution: University of California - Berkeley
EPA Project Officer: Lee, Sonja
Project Period: September 1, 2015 through August 31, 2018
Project Amount: $132,000
RFA: STAR Graduate Fellowships (2015) RFA Text | Recipients Lists
Research Category: Academic Fellowships

Objective:

As there exists only one full-scale, pipe-to-pipe direct potable reuse (DPR) facility in the world, a critical knowledge gap remains regarding the biological stability of drinking water distribution systems (DWDSs) directly fed by advanced treated recycled wastewater. My research will determine if unique microbiological risks exist for direct injection of DPR-treated wastewater streams into a potable DWDS.

Approach:

My research consists of two focuses. First, I will use flow cytometric methods and 16S rDNA sequencing to characterize the impact of advanced treatment on the microbial stability and bacterial communities in DPR treatment systems. Second, I will feed model DWDSs with DPR-treated waters, and compare the microbial water quality and bacterial communities of these model systems to conventional DWDSs.

Expected Results:

Flow cytometry will spotlight the significant rejection or inactivation of bacterial cells by advanced processes in DPR. A small amount of biodegradable organics will likely pass through potable reuse treatment, thereby leading to an unknown amount of bacterial regrowth in the DWDS. Bacterial community analyses using 16S sequencing will yield insight into the differences in the bacterial communities that exist in DPR influent and effluent waters and in downstream DWDSs.

Supplemental Keywords:

direct potable reuse, 16S rDNA sequencing, flow cytometry, biological stability

Progress and Final Reports:

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.