1510461FahrenfeldSince wastewater treatment systems are designed to inactivate infectious agents, the Center for Disease Control (CDC) allows urine and fecal matter from patients with infectious diseases to enter sanitary sewers. However, sewer overflows during wet weather flow are a widespread issue in the US. Sewer solids are a major contributor to pollution during urban wet weather flows. Therefore, sewers are not merely a conduit for wastewater, but rather, complex bioreactors: microorganisms can decay, grow, and have their transport attenuated during conveyance. Surprisingly little is known about the biological processes which occur the sewer deposits and their effect on the fate of microbial agents (i.e., pathogens and antibiotic resistant bacteria) and that is the objective of this proposed project. To perform Quantitative Microbial Risk Assessment for overflow events, optimize sewer maintenance plans, and design wet weather flow treatment, it is necessary to understand the processes affecting the survival of microbial agents (here defined as pathogens and antibiotic resistant bacteria) in sewer solids and biofilms. This is especially true in the case of sewer overflows, but is also important in order to use sewer samples for tracking the incidence of human disease. Sewer surveillance is a useful tool for epidemiology that would benefit from improved understanding of the fate of microbial agents during conveyance in sewer systems. A field survey will be performed to determine the biochemical factors driving the microbial quality of sewer deposits and the relative loading of microbial agents in wastewater and sewer deposits. Next, a controlled simulated sewer experiment will be performed to determine the fate of microbial agents in sewer deposits to provide kinetic data in sewer sediments and biofilm. Finally, a combined sewer overflow (CSO) event will be sampled to characterize the flux of the microbial agents during wet weather flow events. This field study will use the microbial signatures of sewer sediments developed to differentiate between the flux of microbial agents from sewer solids and wastewater. High-throughput, viability-based molecular assays will be applied in this study and allow for sensitive detection of pathogens and the determination of the dynamics of the viable and non-viable antibiotic resistance gene loads. This understanding is essential for determining the risk posed by antibiotic resistant genes in sewer sediments upon release in the environment. Overall, the proposed project will provide critical insight into the fate of microbial agents in sewers and during wet weather flow. The research approach extends biomolecular analytical methods for understanding the fate of microbial agents in sewer deposits. The quantitative data gathered on the environmental factors driving the proliferation of pathogen and antibiotic resistance in sewers will inform quantitative microbial risk assessment, improve models of wet weather pollution events, and aid in the development of mitigation strategies. Of particular interest is the potential application of the knowledge gained here on in-sewer biological processes for improved implementation of sewer surveillance for tracking infectious disease. Sewer epidemiological methods are currently limited by our lack of understanding of critical environmental factors and biochemical processes driving the fate of microbial agents in sewers. Therefore, this work has the potential to transform not only our ability to protect public health during wet weather flow, but also our ability to perform public health surveillance in the sewer matrix. The project targets: (1) recruiting and retaining undergraduate women students in engineering; and, (2) improving scientific literacy. Educational materials and learning modules will be developed and presented biannually in STEM outreach to Girl Scouts (grades 6-12) and at Rutgers Day. A project website will be created to improve public scientific literacy and broaden public knowledge of CSO issues.
|Effective start/end date||3/15/16 → 2/28/19|
- National Science Foundation (National Science Foundation (NSF))