Sarah Potgieter

Research Investigator

Contact information

Email: spotgiet@umich.edu

Researchgate: https://www.researchgate.net/profile/Sarah_Potgieter

Linkedin: https://www.linkedin.com/in/sarah-potgieter-911ba3146/

Career to Date

  • Research Investigator, University of Michigan, USA (2024 – present)
  • Postdoctoral research fellow, University of Michigan, USA (2019 – 2024)
  • Ph.D. in Microbiology, University of Pretoria, South Africa (2019)
  • M.Sc. in Microbiology, University of Pretoria, South Africa (2013)
  • B.Sc. Honors in Microbiology, University of Pretoria, South Africa (2009)
  • B.Sc. in Microbiology, University of Pretoria, South Africa (2008)

Areas of Interest

My interests lie at the intersection of microbiology and environmental engineering, specifically in drinking water treatment and distribution systems. My research focusses on the impact of treatment processes (i.e. biofiltration, disinfection and UV irradiation), operational conditions on the composition, diversity and function of the microbial communities in the treatment plant and distribution system. More specifically, my research has focused on the dynamics of potential problematic microbes such as opportunistic pathogens and nitrifiers. Using my skills in modern molecular methods together with analyzing complex water quality data sets, I aim to reveal the impact of process, infrastructure, and environmental factors on the drinking water microbial community, and potentially offer opportunities to re-think microbial management in drinking water systems.

Research Projects

My current research projects include (i) investigating the complex biogeography of nitrifiers in drinking water systems and the role of biofiltration in seeding the distribution system with nitrifiers, (ii) understanding the impact of low-dose UV irradiation on the drinking water microbial community with special interest in nitrifiers and nontuberculous mycobacteria (NTM), (iii) investigating microbial community acclimation and nitrifier abundance during biofilter start-up, (iii) examine the impact of operational parameters and biomass activity and contaminant control by GAC filters at full-scale and pilot-scale.

Publications:

  • Lee, S., Sun., S., Kirisits, MJ., Raskin, L., Kumpel, E., Lanzarini-Lopes, M., Vedrin, M., Xian, Y., Shakhawat, M., Chavarria, K., Guikema, S., Shen Y., Fan, S., Sela, L., Rahim, N., Potgieter, S., Dowdell, K., and Szczuka, A. 2025. Moving beyond the silos of opportunistic pathogen and disinfection byproduct research to improve drinking water system management. Accepted to Environmental Science and Technology (04/08/2025).
  • Dowdell, K.S., Potgieter, S., Olsen, K. G., Lee, S., Vedrin, M., Caverly, L., LiPuma, J. J. and Raskin. L. Source-to-Tap Investigation of the Occurrence of Nontuberculous Mycobacteria in a Full-Scale Chloraminated Drinking Water System. Submitted to Applied and Environmental Microbiology (4/16/2024). Available on BioRxiv https://doi.org/10.1101/2024.04.18.590135. 
  • Potgieter, S., Dai, Z., Havenga, M., Vosloo, S., Sigudu, M., Pinto, A. and Venter, S., 2021. Reproducible microbial community dynamics of two drinking water systems treating similar source waters. ACS ES&T Water, 1(7), pp.1617-1627.
  • NandaKafle, G., Huegen, T., Potgieter, S.C., Steenkamp, E., Venter, S.N. and Brözel, V.S., 2021. Niche preference of Escherichia coli in a peri-urban pond ecosystem. Life, 11(10), p.1020.
  • Potgieter, S.C., Dai, Z., Venter, S.N., Sigudu, M. and Pinto, A.J., 2020. Microbial Nitrogen Metabolism in Chloraminated Drinking Water Reservoirs. mSphere, 5(2).
  • Potgieter, S., Pinto, A., Sigudu, M., Du Preez, H., Ncube, E. and Venter, S., 2018. Long-term spatial and temporal microbial community dynamics in a large-scale drinking water distribution system with multiple disinfectant regimes. Water research, 139, pp.406-419.

Manuscripts in Preparation:

  • Potgieter, S., Vosloo, S., Langenfeld, K., Dowdell, K., Vedrin, M., Pinto, A & Raskin, L. “Biofiltration and Temporal Dynamics Shape Nitrifier Communities in a Chloraminated Full-Scale Drinking Water Distribution System.” To be submitted to Applied and Environmental Microbiology in August 2025.
  • Potgieter, S., Lee, S., Lahr, R., Steglitz, B and Raskin, L. “Impact of low dose UV treatment on microbial communities in a full-scale drinking water distribution system.” WRF project #5151 to be published in August 2025.
  • Lee, S., Potgieter, S., Vedrin, M. and Raskin, L. “The impact of conventional flushing on nontuberculous mycobacteria and nitrifier abundances in drinking water distribution system dead ends”. To be summitted to Environmental Science and Technology in August 2025.
  • Hegarty, B., Lee, S., Bastien, E., Potgieter, S., Raskin, L., Duhaime, M and Wigginton, K. “Viral-bacterial infection networks within a drinking distribution system”. To be submitted to Water Research in November 2025.
  • Dowdell, K. S., Song, H., Gabrielli, M., Lee, S., Olsen, K. G., Potgieter, S., Vedrin, M., Pinto, A., Delafont, V. and Raskin, L. “Free-living amoebae diversity through drinking water treatment and distribution.” To be submitted to Applied and Environmental Microbiology in December 2025.

Conferences and Presentations:

  • Potgieter, S., Lahr, R., Alfahham, N., Lee, S., Sandoval, S., Guo,Y., Steglitz, B & Raskin, L. Culture-independent methods to investigate the impact of UV irradiation on drinking water microbial communities. Special Topic Session (STS) titled “Standard culture- and advanced molecular-based testing for microbiology: the cornerstone for the protection of public health”. Water Quality and Technology Conference (WQTC), Dallas, Texas, USA, November 2023. 
  • Potgieter, S., Lahr, R., Vosloo, S., Dowdell, K., Vedrin, Page, S., Bautista-de los Santos, Q., Keown,J., Quneibi, T., Alfahham, N., Lee,S., Sandoval,S., Guo,Y., Pinto,A., Steglitz, B & Raskin, L. Assessing the impact of drinking water treatment on distribution system nitrifier populations: Collaborations between the City of Ann Arbor drinking water treatment plant and the University of Michigan. Borchardts Conference, Michigan, USA, May 2023
  • Potgieter, S., Vosloo, S., Dowdell, K., Vedrin, M., Lahr, R., Page, S., Pinto, A & Raskin, L. The role of biofiltration in shaping drinking water distribution system nitrifier populations, MAC-EPID pre-symposium workshop, “Ecology, evolution and the microbiome: From mechanisms to translation. Michigan, USA, March 2023
  • Potgieter, S., Lahr, R., Vosloo, S., Dowdell1, K., Vedrin, Page, S., Bautista-de los Santos, Q., Keown,J., Quneibi, T., Alfahham, N., Lee,S., Sandoval,S., Guo,Y., Pinto,A., Steglitz, B & Raskin, L. Assessing the impact of drinking water treatment on distribution system nitrifier populations, South Dakota State University Crother’s Seminar, South Dakota, USA, March 2023.
  • Potgieter, S., Bautista, M., Page, S., Keown, J., Lahr, R., Olson, T. & Raskin, L. Understanding nitrification through biofilter start-up and acclimation. City of Ann Arbor drinking water treatment plant, Lunch and Learn. Michigan, USA, March 2022
  • Potgieter, S., Bautista, M., Page, S., Keown, J., Lahr, R., Olson, T. & Raskin, L. Nitrifier dynamics during biofilter start-up and acclimation in full-scale drinking water treatment plant, Water Quality and Technology Conference (WQTC), Tacoma, Washington, USA, Nov 2021.
  • Venter, S. N., Pinto, A., Potgieter, S. and Bezuidenhout, C. Making sense of the drinking water microbiome. Workshop presented at Water Institute of South Africa (WISA) conference, Cape Town, South Africa, June 2018.
  • Potgieter, S., Venter, S. N and Pinto, A. Microbial nitrogen metabolism in chloraminated drinking water reservoirs. Oral presentation by SC Potgieter at the South African Society of Microbiology conference, Johannesburg, South Africa, April 2018.
  • Potgieter, S., Pinto, A., Sigudu, M., EJ Ncube. E. J., du Preez, H and Venter, S. N. Long-term spatial and temporal microbial community dynamics in a large-scale drinking water distribution system. Poster presented by SC Potgieter at the IWA International Young Water Professional Conference, Cape Town, South Africa, December 2017.
  • Potgieter, S., Pinto, A., Sigudu, M., EJ Ncube. E. J., du Preez, H and Venter, S. N. Microbial community structure and diversity of a large-scale South African drinking water distribution system. Poster presented by SN Venter at the 7th congress of the Federation of European Microbiological Society (FEMS), Valencia, Spain, July 2017.
  • Potgieter, S., Pinto, A., Sigudu, M., EJ Ncube. E. J., du Preez, H and Venter, S. N. Long-term spatial and temporal microbial community dynamics in drinking water distribution systems: A South African case study. Poster presented by SC Potgieter at the IWA UNC Water Microbiology conference held in Chapel Hill, North Carolina, USA, May 2017.
  • Potgieter, S., Steenkamp, E., V, Brozel and Venter, S. N. Investigations into the existence of unique environmental Escherichia coli populations. Oral presentation by SC Potgieter at South African Society of Microbiology conference (SASM), Cape Town, South Africa, November 2011