Microbiological Water Quality Analysis of San Juan Bay Estuary
Citation:
Soto Buonomo, V., I. Cappielo Cosme, E. Villafane Deyack, M. Molina, A. Oczkowski, Alana Hanson, M. Schwartz, D. Katz, E. Huertas, AND N. Soto-Nieves. Microbiological Water Quality Analysis of San Juan Bay Estuary. Health and Climate Summit 2022, St Thomas, VI, June 06 - 10, 2022.
Impact/Purpose:
The objective of this research is to assess and further understand the water quality impacts of the Can¿o Martin Pena (CMP) closure and sewage-enriched urban runoff on the San Juan Bay Estuary system. The results indicate that enterococci criteria is exceeded most of the time in certain locations, but particularly at (CMP), which exhibits the poorest surface water quality in the SJBE. E. coli criteria is also exceeded. The level of impact suggests sanitary discharges are occurring at a regular basis.
Description:
Increased precipitation due to climate change poses significant challenges in urbanized tropical coastal systems. Our study system, the San Juan Bay Estuary (SJBE), located in northeast Puerto Rico, is no exception. This ecosystem includes five lagoons interconnected by channels, provides habitat for a diverse range of fauna and flora, and is home to 33% of the mangrove area in Puerto Rico. Due to lack of proper or nonexistent sanitary and stormwater sewer infrastructure, eight communities surrounding one of the main connecting channels, the Caño Martín Peña (CMP) are frequently flooded by polluted waters, making this situation one of the most relevant environmental justice issues on the Island. Public health studies have reported high prevalence of gastrointestinal diseases, asthma, and atopic dermatitis among the CMP community compared to the rest of the population. To assess the potential risk to human health due to the input of sewage, water samples were collected throughout the SJBE twice monthly for 12 months. Enterococcus concentrations were quantified using the defined substrate method and quantitative PCR. Preliminary results indicate large fluctuation in the enterococci levels across the SJBE, with the four CMP stations exceeding the Enterococcus criteria (35 CFU/100 ml) a 100% of the time, and10% exceeding the maximum assay detection limit (MADL, 2.4 x104 CFU/100 ml). In contrast, other SJBE stations exceeded criteria levels 36% of the time, and the MADL was not exceeded. High concentrations of Enterococcus coincided with low salinity, suggesting that sewage loads may be entering the water, and creating microbial hot spot zones. These results help identify and evaluate areas of the estuary in need of environmental restoration and provide information to help reduce health impact in CMP communities in contact with contaminated flooding waters.
