Rapid: Response to Massive Sewer Blockage for Immediate Flood Mitigation and Future Remedies

Wayne State University, Detroit MI

Investigators

Abstract

Part 1 This project focuses on the recent Macomb County, Michigan blockage of an 11-foot diameter sewage line. The blockage threatens raw sewage back-up into thousands of homes. The source of the blockage is a massive build-up of fats, oils, and greases (FOGs) discharged into the sewer by homes, industry, and restaurants. Such massive FOG buildups have been termed "fatbergs" in the popular press, and their impact on the environment is potentially severe. To avoid basement flooding, millions of gallons of untreated sewage have been discharged into the nearby Clinton River. Such releases threaten the health of the river and the downstream Great Lakes ecosystem. Although FOG blockages have been known for several years, our understanding of their detailed chemical structure is lacking due to their infrequent and unpredictable formation. The formation and planned removal of such a massive FOG blockage presents a rare opportunity to study these formations. This project will utilize real-time video, pressure data, and advanced chemical analysis to advance our understanding of the physical and chemical structure of FOG blockages. The results will be used to identify potential risks associated with blockage and inform future targeted prevention/mitigation efforts. A public outreach and education program will be developed in conjunction with the Michigan Science Center to increase awareness and understanding of the impacts of sewer backups. Part 2 The most common cause of large-scale sewer blockage is the growth of highly viscous and dense conglomerations of fats, oils, grease (FOGs) and solids, including baby wipes and other products. These growths are also known as "fatbergs". Given that a majority of toxicants of concern to human health are lipophilic (attracted to fats), these accumulations have a high potential to pose a significant health risk. The objective of this study is to identify contaminants of interest in the fatberg by extracting and evaluating the chemical concentrations of EDCs, PFAS, and other emerging contaminants including pesticides, pharmaceuticals, and personal care products. The intellectual merit derives from the knowledge gained from a once-in-a-lifetime opportunity to evaluate a massive fatberg and reconstruct the hydraulic conditions associated with its presence in the system. The project will lead to new information about the chemistry and hydraulic characteristics of fatbergs and the environmental considerations associated with their growth. Broader impacts from this project will arise due to the collaboration with the Michigan Science Center, which is designing an educational centerpiece for the museum about the occurrence of such blockages, and actions that the public can adopt to mitigate the occurrence. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.