Purpose
From the moment I joined Florida Sea Grant our community has been concerned with the number of health advisories issued in the Pensacola Bay area. Bayou Chico is our local BMAP waterway (Basin Management Action Plan) which is required by the state due to being severely impaired. Bayou Chico is so because of the fecal bacteria issue. Advisories are issued based on the concentration of fecal bacteria in the water. Obviously, fecal bacteria come from waste, but animals do produce waste and it is not surprising that these bacteria are detected. The issue is not presence/absence, it is concentration – how much is there.
The fecal bacterium used as an indicator in estuarine and marine systems is Enterococcus. This bacterium is found in the digestive systems of birds and mammals, including humans. The presence of this bacterium does not immediately mean a human waste issue, but large concentrations could. Studies suggest that concentrations of 71 colonies (or more) in a 100-ml sample are high enough to warrant advisory. Each week, the Florida Department of Health samples water near locations where people like to swim and recreate. These samples are analyzed and, for Enterococcus, if at 71 colonies or higher a second sample is collected. If it remains at 71 colonies or higher a health advisory is issued.
Due to cost, not every waterway is sampled every week. In the Pensacola area some are monitored all year. Some are not monitored in the winter (when no one is swimming). A few are only monitored in the summer. So, for our purposes, we do not log how many advisories were issued for each body of water, but rather what percentage of the samples collected required a heath advisory.
When we first began monitoring the health department’s data, the swimming area in the lower portions of the bay (the beaches) rarely saw an advisory – typically less than 5% of the samples and for several locations it was 0%. However, the bayous were different. Grande, Chico, and Texar ran at above 30% most years. Florida Sea Grant hopes, with improve infrastructure and education, the bayous will decrease the percentage of advisories they see annually.
Percentage of Advisories as of the 3rd Quarter of 2023
| Body of Water | # of samples | # of POOR reports | # of advisories | % of advisories |
| Bayou Texar | 39 | 7 | 7 | .18 |
| Sanders Beach | 40 | 6 | 2 | .05 |
| Bruce Beach | 40 | 9 | 4 | .10 |
| Bayou Chico | 17 | 4 | 3 | .18 |
| Bayou Grande | 17 | 4 | 4 | .24 |
| Big Lagoon SP | 18 | 1 | 1 | .06 |
| Casino Beach | 17 | 1 | 0 | .00 |
| Park East | 17 | 0 | 0 | .00 |
| Park West | 17 | 0 | 0 | .00 |
| Quietwater Beach | 17 | 1 | 0 | .00 |
| Ft. Pickens | 7 | 0 | 0 | .00 |
| Opal Beach | 7 | 1 | 0 | .00 |
| Johnson’s Beach | 7 | 0 | 0 | .00 |
| TOTAL | 260 | 34 | 21 | .08 |
Discussion
As you can see, so far in 2023 it has been a good year for advisories – less than 10% of the samples have required an advisory. All three of the bayous are below 30%, actually they are all below 25%. The results of this update could be due to major sewer infrastructure improvements made in neighborhoods within these watersheds. It could be from educating the public about maintaining their septic or sewer systems. But there has also been a positive correlation between the amount of rainfall we get, and the number of advisories issued. It has been a very dry year. Historically Pensacola receives around 60 inches of rain each year. In the last decade it has been closer to 70 inches. As of this report we have received 50.34 inches in 2023, lower than our historic mean. This too could play a part in the lower percentages of advisories.
The final report for 2023 will be posted in late December.
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