Breannahenryportfolio.com - Analyzing Microbial Content of Water Samples

Analyzing Microbial Content of Water Samples in New York City and New Jersey

During the Summer of 2025, I worked as a Water Quality Monitoring Intern with the Interstate Environmental Commission (IEC), contributing to regional efforts to analyze and protect water bodies across the tri-state area. I supported the Coordinated Volunteer Water Quality Monitoring Program by picking up weekly surface water samples from volunteer groups with sites across New York and New Jersey. Using Fecal Coliform Membrane Filtration and Enterolert IDEXX methods, I analyzed bacteria count and developed graphs of Enterococci and Fecal Coliform concentrations across all sites over the course of my 12-week internship. Interpreting these trends revealed a clear correlation between rainfall events, stormwater runoff, and bacteria spikes, highlighting the influence of urban infrastructure and environmental stressors on water quality. This project strengthened my ability to translate field and laboratory data into actionable insights and reinforced the role of evidence-based environmental monitoring in supporting resilient, sustainable urban systems.

Work sample of the data table that I had to fill out for each group over the course of my internship. The example chart shows the data for our volunteer group in Rahway, New Jersey. The table shows the name of the site, the field data collected from the site, the results of microbiology testing for each site, and the tide and weather conditions of the testing site on the day the sample was taken. The data in this table was used to create graphs highlighting the Fecal Coliform count and Enterococci count of each site.

Work samples of graphs recording Enterococci and Fecal Coliform count over the 12-week internship. Example data is taken from the Rahway Riverfront Park site.

Work samples of graphs recording Enterococci and Fecal Coliform count over the 12-week internship. Example data is taken from the Rahway Sewage Authority site.

Work samples of graphs recording Enterococci and Fecal Coliform count over the 12-week internship. Example data is taken from the Carteret Waterfront Park site.

The data shown above were repeated for eight other groups that participate in the Volunteer Water Quality Monitoring study conducted by the Interstate Environmental Commission.