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Studying Richmond’s combined sewer system’s effect on antibiotic resistance in the James River

Mary Coughter on the river
Mary Coughter sampling at Reedy Creek, one of the city’s 25 combined sewer system sites and a popular spot for recreation on the James River. (Photo: Aoife Mahaney)

I am a life science Ph.D. student at Virginia Commonwealth University, an institution known for its arts school, in the city of Richmond, a town full of creative types. I’ve always thought of myself as a creative person, but more in the way I think than in the actual creation of art. Part of what excited me about microbiology was its ability to spark my artistic side in a way I hadn’t found in school before. For instance, the ability to uncover something hidden (at least not seen by the naked eye) just by manipulating the conditions an organism is under, feels like an art form to me. The ways that bacteria grow on plates can even be beautiful [see Smithsonian article on agar art]. 

My early microbiology classes helped me see the world in a new way, realizing how microbes impact our everyday lives. Microbes play a pivotal role in food production like bread baking, beer brewing and yogurt making. Microorganisms exist everywhere on Earth, from hot springs to the arctic. Therefore we also find microorganisms in environments all around us, like in the river that runs through our city and state, and we study them to predict human health outcomes.

Richmond serves as the backdrop for my research; a mid-sized city with a large hospital system, known for its recreation on the James River. The James is one of the largest tributaries of the Chesapeake Bay, meaning that the health of the James River impacts a wide geographical area and population. Richmond is also home to a combined sewer system, which aims to keep sewage out of the river. Combined sewers are a fixture in cities across the United States and world, but many were built decades ago, when cities served much smaller populations. 

Overflows of these systems are becoming more frequent and potentially more detrimental alongside increasingly extreme weather events. When these overflows occur, the city of Richmond is very transparent about water safety, providing a real-time map of overflow events. However, many people still go into the river despite having access to these warnings. When overflows occur, there is heightened potential for contracting an infection. With continued mixing of substances -  human waste, nutrients, and pharmaceuticals - more resistance will emerge in the river’s microorganisms. 

Mary and Ed at Wastewater plant
Coughter and Ed Edmondson, Wastewater Treatment Plant Superintendent, City of Richmond, VA.  (Photo: VPM) 

My research is not intended to scare people from using the James River for recreation, but rather to encourage everyone to protect this amazing resource. I hope my work helps to increase the public’s understanding that environmental health is public health, and that there is much more we can do to maintain and protect our waterways. 

mary and research poser
Coughter presented the work for her master’s degree at the American Society for Microbiology international conference in Washington DC, June 2022. (Photo: Mary Coughter)

Mary Coughter fell in love with the outdoors at her summer camp when she was 11. This passion carried her into majoring in Environmental Science at Virginia Tech. Beginning to work in research labs as a sophomore in college, she became interested in microbiology and its intersection with environmental change. She then moved to Richmond and VCU to earn a master's degree in biology and is now working towards her Ph.D.