Health advisories are issued by the Florida Department of Health to alert the public of high levels of fecal bacteria in the waterways. The indicator bacteria used for these assessments are species of the genus Enterococcus, a common bacteria found in the large intestines of birds and mammals. This bacteria is a natural part of our system and helps with the breakdown of food. Levels of this bacteria are expected to be in local waterways due to the defecation of all birds and mammals. However, high levels of this bacteria could be an indicator of high levels of sewage waste in the waterways – very likely human.
Though Enterococcus itself is not harmful at normal concentrations, it is an indicator that other pathogenic bacteria could be present – thus a health advisory is issued.
High levels defined here would be samples containing 71 (or more colonies) / 100ml of sample. If a lab detects 71/100ml of more, a second sample will be taken to confirm. If confirmed, a health advisory is issued. For our three larger bayous in the Pensacola Bay area – Texar, Chico, and Grande – a second sample may not be taken, and an advisory issued after the first sample.
Below you will see the data table including the number of samples, the numbers of POOR readings (>71 colonies/100ml), the number of advisories issued, and – since not all bodies of water are sampled with the same frequency – the percent of samples taken that required an advisory. My long-term goal is to reduce all percent of samples to <30%.
2018
Water Body | No. of samples | No. of POOR | No. of Advisories | % of Occurrence |
Bayou Texar | 47 | 23 | 23 | 49 |
Sanders Beach | 61 | 20 | 7 | 11 |
Bayou Chico | 20 | 12 | 12 | 60 |
Bayou Grande | 17 | 8 | 8 | 47 |
Big Lagoon SP | 17 | 0 | 0 | 0 |
Perdido Key SP | 15 | 0 | 0 | 0 |
Casino Beach | 16 | 0 | 0 | 0 |
Park East | 16 | 0 | 0 | 0 |
Park West | 17 | 1 | 0 | 0 |
Quietwater | 16 | 1 | 0 | 0 |
Opal Beach | 8 | 1 | 0 | 0 |
Johnsons Beach | 8 | 0 | 0 | 0 |
Ft. Pickens | 7 | 0 | 0 | 0 |
TOTAL | 265 | 66 | 50 | 19 |
2019
Water Body | No. of samples | No. of POOR | No. of Advisories | % of Occurrence |
Bayou Texar | 54 | 16 | 16 | 30 |
Sanders Beach | 58 | 12 | 5 | 9 |
Bayou Chico | 25 | 15 | 14 | 56 |
Bayou Grande | 25 | 7 | 7 | 28 |
Big Lagoon SP | 25 | 1 | 0 | 0 |
Perdido Key SP | 19 | 0 | 0 | 0 |
Casino Beach | 26 | 2 | 0 | 0 |
Park East | 25 | 0 | 0 | 0 |
Park West | 25 | 3 | 1 | 4 |
Quietwater | 25 | 4 | 0 | 0 |
Opal Beach | 13 | 1 | 0 | 0 |
Johnsons Beach | 6 | 0 | 0 | 0 |
Ft. Pickens | 10 | 1 | 0 | 0 |
TOTAL | 336 | 62 | 43 | 13 |
2020
Water Body | No. of samples | No. of POOR | No. of Advisories | % of Occurrence |
Bayou Texar | 43 | 15 | 15 | 35 |
Sanders Beach | 41 | 10 | 8 | 20 |
Bayou Chico | 30 | 12 | 12 | 40 |
Bayou Grande | 23 | 9 | 9 | 39 |
Big Lagoon SP | 20 | 1 | 1 | 5 |
Perdido Key SP | 22 | 0 | 0 | 0 |
Casino Beach | 22 | 1 | 1 | 5 |
Park East | 22 | 2 | 1 | 5 |
Park West | 22 | 2 | 1 | 5 |
Quietwater | 22 | 1 | 1 | 5 |
Opal Beach | 7 | 0 | 0 | 0 |
Johnsons Beach | 0 | 0 | 0 | |
Ft. Pickens | 7 | 0 | 0 | 9 |
TOTAL | 281 | 53 | 49 | 17 |
Results
The number of samples taken by FDOH over the last three years ranges from 265-336 / year.
Bayou Texar and Sanders Beach are sampled more often than the others.
Overall, the percent of samples requiring advisories ranged from 13-19%
The decline in advisories in 2019 may be due to the decrease in rainfall that year.
Both 2018 and 2020 had 60 inches of rainfall, or more. 2019 had 47 inches.
THOSE BODIES OF WATER WITH 30% ADVISORIES OR MORE.
2018 – Bayou Chico (60%), Bayou Texar (49%), Bayou Grande (47%)
2019 – Bayou Chico (56%), Bayou Texar (30%)
2020 – Bayou Chico (40%), Bayou Grande (39%), Bayou Texar (35%)
Discussion
It is pretty obvious that, when considering health advisories, the three bayous are areas of most concern. Each hovers at, or is above, 30% of samples requiring a health advisory being issued.
It is also obvious that when annual rainfall decreases, the number of water bodies with 30% (or more) of their samples requiring advisories does as well. Excessive rainfall can trigger septic tank leaks and drain field flooding, as well as an increase in sanitary overflows of the public sewer systems.
You might notice that even though all three bayous decreased their percent of health advisories issued / sample from 2018 to 2019 (presumably from decrease in rain) that both Texar and Grande’s decreased by 40%. However, Bayou Chico only decreased 7%. This suggests a stronger concerns about Bayou Chico’s situation. Keep in mind that Bayou Chico is sampled less frequently than Bayou Texar, and that increase sampling might change the math some. But Chico IS sampled at about the same rate as Bayou Grande.
You will notice that Sanders Beach, at the mouth of Bayou Chico, is sampled more frequently than all others. It, like Bayou Texar, is sampled once a week. The increase samples over Bayou Texar can be explained by the number of re-samples (required after a POOR reading). Of the 42 POOR samples found at Sanders Beach only 20 (48%) of the re-samples required a health advisory to be issued. Thus, the percent of Sanders Beach samples requiring a health advisory ranges from 9-20% (mean = 12%). One wonders if follow up samples were conducted at the Bayou Chico site would it too decrease? One would then wonder why they do not re-sample?
The quick answer… time and money. Sampling and analyzing for these bacteria can be expensive if numerous samples are taken. There is also the manpower issue on being able to sample that frequently. However, there are other agencies monitoring Bayou Chico (Florida Department of Environmental Protection and Escambia County are two) whose data could see this point clearer. Extension is in a position to work with the county on training volunteers to sample, and have the certified county lab analyze, additional samples. The problem is money. To monitor just one more site on Chico once a week over the course of a year would cost about $2000 just to analyze it.
What Can You Do to Help Reduce the Number of Advisories in Our Bayous?
First, determine if you live within the watershed of any. You can find this by viewing this link: https://fdep.maps.arcgis.com/home/webmap/viewer.html?webmap=1b4f1bf4c9c3481fb2864a415fbeca77
This is not just the folks living ON these waterways, it is impacted by all who live in the WATERSHED of these waterways.
Next, do you have septic tank or are you on the sewer system?
If you are on a septic do the following
- Do not flush anything that is not supposed to end up in your tank. Flushable wipes are flushable, but they are not degradable and can cause plugged pipes and backflow flooding. The same is true with bacon grease, fats, and even milk.
- Have your tank inspected and, if needed, pumped every five years.
- If you have an opportunity, connect with the municipal sewage system.
If you are on the municipal sewage system
Do #1 from above. Sanitary sewage overflows are common and often caused by clogged pipes. Emerald Coast Utility Authority (ECUA) F.O.G. program can help. Their free grease plastic grease containers and drop off locations can be found at https://ecua.fl.gov/live-green/fats-oils-grease. There is one at the Escambia County Extension Office.