Letter to City of Bradenton on Protecting Water Quality in Palma Sola Bay

For Immediate Release

Wednesday, Sep 10, 2025

Contact: Abbey Tyrna, Suncoast Waterkeeper, [email protected]

PRESS RELEASE

Letter to the City of Bradenton Mayor and City Council
Regarding Protecting Water Quality in Palma Sola Bay

September 10, 2025

Mayor and Council
City of Bradenton
101 Old Main Street
Bradenton, FL 34205

Re: Protecting Water Quality in Palma Sola Bay

Dear Mayor and Council,

Thank you for your time and attention to the issue of water quality in Palma Sola Bay. Suncoast Waterkeeper has been monitoring Palma Sola Bay north of the causeway (also known as North Bay or Little Palma Sola Bay) for several years. Since I joined the organization in 2022, we have collected consistent data from the same location each week, west of the area where horses are staged.

Our monitoring results reveal persistent exceedances of the state’s water quality standards for enterococci bacteria:

• 2022: 22 samples collected, 6 exceeded the FDEP threshold of 130/100 mL (no more than 4 should exceed).
  
  
• 2023: 46 samples collected, 23 exceeded (no more than 8 should exceed).
  
  
• 2024: 43 samples collected, 20 exceeded (no more than 8 should exceed).
  
  
• 2025 to date: 32 samples collected, 16 exceeded (no more than 6 should exceed)

These results indicate that the monitored area consistently fails to meet water quality standards for its designated use as a Class III recreational waterbody (Chapter 62-302 of the Florida Administrative Code (F.A.C.).

In addition to routine monitoring, we sought to better understand potential sources of bacteria in this area. With a private donation from a local resident and grant funding, we contracted LuminUltra to perform quantitative polymerase chain reaction (qPCR) microbial source tracking tests in 2024 and 2025. The results were as follows:

• April 2024: Horse DNA was detected and quantified in both water and sediment; no human DNA was detected.
  
  
• July 2024: Horse DNA was again quantified in water samples; human DNA was detected, but at levels below quantification.
  
  
• April 2025: Avian DNA was detected at low levels; neither horse nor human DNA was detected in the sample.

These findings demonstrate that horses are a measurable source of bacterial pollution in Palma Sola Bay north of the causeway; however, they are not the sole contributor. The scientific literature emphasizes that microbial contamination in coastal waters frequently originates from multiple sources, including wildlife, domestic animals, and human infrastructure, and that distinguishing between these inputs and their relative contributions is inherently challenging (Harwood et al., 2014; Boehm & Sassoubre, 2014). While microbial source tracking tools, such as qPCR, provide valuable insights, the complexity of environmental conditions means that no single test can fully quantify or apportion all sources of bacteria (Layton et al., 2013).

This is not a call to remove horses from the bay. Instead, we support a balanced approach that protects water quality while promoting responsible recreational use. Specifically, we recommend the following actions:

1. Install Public Signage – Post clear warning signs alerting residents and visitors that enterococci levels exceed state water quality standards, so that people can make informed decisions about their health and recreation.
   
   
2. Establish a Horse Vendor Permit System – Create a permit program that caps the total number of horse vendors and requires best management practices (BMPs) designed to protect water quality and seagrass meadows. Such BMPs should include ensuring horses remain in shallow water for the majority of the ride, only wading in past their hindquarters for a short duration at the beginning, and requiring the use of waterproof horse diapers. The permit should also stipulate the area where the horses can ride to protect the seagrasses.  

Several horse vendors have expressed support for a permit system, noting that it would help prevent overcrowding and reduce conflicts with out-of-area operators. While some vendors have been hesitant about BMPs, these measures are essential for protecting Palma Sola Bay, a vital ecological, commercial, and recreational resource for the Bradenton community.

 

We request that the City of Bradenton take action to safeguard the health of Palma Sola Bay and its residents by implementing these two measures. Suncoast Waterkeeper stands ready to provide additional data and to work with you on solutions that balance recreation, local business, and environmental protection.

Thank you for your consideration and commitment to clean water.

—UPDATE POST-CITY COMMISSION—

According to Byappanahalli et. al (2012), enterococci are not confined to fresh fecal inputs. They can survive, persist, and even regrow in environmental reservoirs such as beach sand, seaweed wrack, sediments, and decaying vegetation. Because these reservoirs release bacteria back into the water column, concentrations can remain elevated even after an obvious source (e.g., a leaking septic tank or animal activity) is eliminated.  Enterococci can multiply in nutrient-rich soils and decomposing plant material under warm, moist conditions, which are abundant on the Suncoast. This means that once introduced, they may establish local populations that maintain detectable levels, independent of ongoing fecal input.  Together with other sources of enterococci in Palma Sola Bay, this means that we may not be able to detect the signal of the elimination of a single source (e.g., the horses) among the noise.  

Requiring horse vendors to forfeit a month of income is neither fair nor effective. A more responsible use of resources involves developing and implementing best management practices in collaboration with stakeholders, and then evaluating their effectiveness after a reasonable period. This path not only protects water quality but also supports the livelihoods and recreational opportunities that Palma Sola Bay depends on. It is a balanced, evidence-based solution that avoids unnecessary economic harm while advancing our shared environmental goals.

 

Sincerely,

Abbey Tyrna
Waterkeeper & Executive Director

 

References:

Boehm, A.B., & Sassoubre, L.M. (2014). Enterococci as indicators of environmental fecal contamination. Enterococci: From Commensals to Leading Causes of Drug Resistant Infection. NCBI Bookshelf.

Byappanahalli, M. N., Nevers, M. B., Korajkic, A., Staley, Z. R., & Harwood, V. J. (2012). Enterococci in the Environment. Microbiology and Molecular Biology Reviews, 76(4), 685–706. https://journals.asm.org/doi/epub/10.1128/mmbr.00023-12

Harwood, V.J., et al. (2014). Microbial source tracking markers for detection of fecal contamination in environmental waters: relationships between pathogens and human health outcomes. FEMS Microbiology Reviews, 38(1), 1–40.

Layton, B.A., et al. (2013). Performance of human fecal anaerobe-associated PCR-based assays in a multi-laboratory method evaluation study. Water Research, 47(18), 6897–6908.