Blaney Lab identifies impacts from failing sewer systems

Congratulations to Jahir Antonio Batista Andrade, Ph.D. Candidate in Environmental Engineering, on his first publication related to his Ph.D. research. Batista Andrade, under the supervision of Dr. Lee Blaney, worked with a team of researchers including undergraduate (Erick Diaz, ‘21 Chemical Engineering & Diego Iglesias Vega, ‘23 Chemical Engineering) and graduate students (Ethan Hain, Ph.D. ‘22 Chemical and Biochemical Engineering) as well as postdoctoral researchers (Michael Rose) from Blaney Lab on the research published in the Water Research journal.

The journal article is titled: “Spatiotemporal analysis of fluorescent dissolved organic matter to identify the impacts of failing sewer infrastructure in urban streams”. The findings of this study describe the use of fluorescence excitation-emission matrix (EEM) spectroscopy and parallel factor analysis (PARAFAC) to track hotspots of raw wastewater in urban streams. The study analyzed 296 surface water samples from 27 sites in two watersheds over a one-year period and found that the area-normalized ratio of soluble microbial product-like to humic acid-like fluorescence (R4/R5 ≥ 0.85) and the ratio of EEM-PARAFAC components with tryptophan-like and fulvic acid-like fluorescence (C4/C3 ≥ 1.45) could be used to distinguish when and where untreated wastewater is introduced to these streams.

The researchers validated the proposed ratios by detecting contaminants such as sucralose, antibiotics, and UV filters in the samples. They identified three sites impacted by septic systems and ten sites affected by sanitary sewer overflows and/or sewer exfiltration. These hotspots occurred almost every month, with the majority being identified in the spring and early summer.

The study's findings suggest that EEM-PARAFAC-based wastewater indicators could be a quick, easy, cost-effective, and scalable technique for identifying failing sewer infrastructure in low-order streams. This is important as failing infrastructure can introduce raw wastewater into these streams, potentially causing environmental and public health issues.