Water quality in the Pensacola Bay System has been an issue with local citizens for many years. There are a variety of issues, but the levels of fecal bacteria have been one that has drawn attention in the last decade. Fecal bacteria are those associated with the large intestines of birds and mammals and find their way into our waterways via defecation. These bacteria are used as an indicator of animal waste in the waters. The presence of these could indicate the presence of pathogens associated with animal waste that could be a risk to human health. When levels are too high health advisories are issued to the public asking them to restrict water activities in those bodies of water.
The bacterium used for monitoring saline waters is Enterococcus. When concentrations of these bacteria reach 71 colonies/100ml of sample (or higher), a re-test is conducted. If the values are at those levels on the second run, a health advisory is issued for that body of water. Locally, the Department of Health usually collects at the beginning of the week, run second samples (if needed) midweek, and post any needed health advisories at the end of the week.
Due to the cost of analyzing these samples, the Department of Health only samples waterways that are frequently used by locals for recreation, and during the months when they are being used. Some water bodies are sampled every week, others during spring-summer-fall, others only in the summer. Thus, not every water body is monitored at the same frequency. Because of this Sea Grant does not report the number of health advisories for each water body but the percentage of those sampled that required a health advisory.
Using this method, the public recreation areas at the south end of the bay system (Pensacola Beach and Perdido Key) rarely see health advisories. Over the years we have been monitoring, these bodies of water usually see the percentage of health advisories issued at, or less, than 5% of the samples taken. For many it has been 0% over the last decade. However, in the upper parts of Pensacola Bay, particularly the bayous, the percentages are higher. Over the last decade the percentages for the three bayous (Texar, Chico, and Grande) have been near, or above, 30% of the samples. Bayou Chico has had years when the percentages were at or above 60% of the samples collected.
Both the city and the county have conducted infrastructure projects designed to reduce this problem, ECUA has as well, and Sea Grant has been providing education information on how to help to the public for a decade now. It is our hope that the number of health advisories in the local bayous will drop below the 30% of sample mark. Here is the data for 2023 up to the end of spring (June).
Health Advisories for 2023 – data provided by the Department of Health
|Body of Water||No. of samples collected||No. of POOR reports||No. of Advisories Issued||Percent of samples collected requiring an advisory|
|Big Lagoon State Park||14||1||1||.07|
You will notice that as of the end of spring this year no body of water has a percentage of 30% or higher. This is a reduction of what we have seen in past years. Several studies suggest a positive correlation between the number of health advisories and the amount of rainfall. Historically Pensacola receives about 60” of rain each year, making it one of the wetter locations in the southeast. However, the last decade this has increased to around 70” each year. This would suggest an increase in health advisories over the last decade as well. As of the time of this writing we have logged 44.70” of rain this year in Pensacola. Though we know this will change between now and Christmas, currently we are on target to reach 67” this year. Though above our historic norm, it is below where we have been in recent years. This reduction in rainfall may have influenced the number of health advisories to date. We will see how this will progress as the year continues.
Another thing to keep in mind are the infrastructure improvements conducted by the local governments and agencies. We are also hoping local residents are adopting behaviors within their homes that can help reduce advisories as well. If you would like to learn what some of these behaviors are, contact me at the Escambia County Extension Office (850-475-5230ext.1111), firstname.lastname@example.org.