Microbial Source Tracking for Florida Local Government
Saint Petersburg
Our project with the City of St. Petersburg is one of our longest ongoing projects. Since 2019, we have worked to determine the presence and level of anthropogenic, human sewage-associated bacterial contamination in urban fresh water bodies in St. Petersburg, FL. Every month, water samples collected from eight water bodies in St. Petersburg (Figure 1) are analyzed for the sewage marker HF183, using the sewage marker H8 in culturable E. coli as a confirmation.
Hillsborough
Figure 1. Sampling sites in St. Petersburg
Working with Hillsborough County Environmental Services, we have investigated several water bodies in the Hillsborough area, including Turkey Creek, Egypt Lake, the Alafia River, Buckhorn Creek, and Rice Creek. From water samples at sites in these water bodies, we looked for culturable fecal indicator bacteria and DNA markers to identify sources of fecal pollution.
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At Turkey Creek (Figure 2), pollution in the downstream part of the creek (part C in Figure 2) was determined to be due to cattle that lived nearby the creek as well as discharged treated wastewater effluent. Additionally, upstream pollution (part A in Figure 2) was found to be due to a pipe delivering sewage into the creek, which was then removed. A case study in Turkey Creek was included in a publication by Lobos et al., 2024. In Egypt Lake, our investigation led to the mending of a pipe that was suspected to be contributing to the bacterial load.
The project in the Alafia River, Buckhorn Creek, and Rice Creek is ongoing, and expected to wrap up in April of 2025.
Figure 2. Sampling sites in Turkey Creek
Sarasota
We have recently begun working with the City of Sarasota to analyze potential sources of contamination in several of their waterbodies. The study aims to determine if sewage is a substantial source of contamination in Whitaker Bayou and Hudson Bayou. The project will be wrapping up in May 2025.
Water Keepers
This study, funded by the Tampa Bay Water Keepers, began in May of 2024 and will be wrapping up in April of 2025. Three sites in three separate water bodies were analyzed for E. coli and DNA markers to identify potential sources of fecal contamination. Additionally, the H8 gene in culturable E. coli will be used to confirm the presence of sewage.