During a presentation on nutrient loads caused by septic systems before the Florida Senate Appropriations Subcommittee on Agriculture, Environment and General Government, Dr. Brian E. Lapointe, a research professor at Florida Atlantic University, said septic tanks are a major factor behind a recent spike in harmful algal blooms. A problem that, in his opinion, is “the most important and urgent issue facing our state.”
Lapointe explained to the committee members gathered in Tallahassee Wednesday morning that nitrogen is the main driver of algae blooms and, although nitrogen fertilizer production has risen rapidly, septic tanks are the main culprit.
A recent Florida Department of Environmental Protection (DEP) study of Wakulla Springs just south of Tallahassee found that 51 percent of the nitrogen in that system was coming from septic tanks. A similar study at Silver Springs near Ocala in Central Florida found that about 40 percent of the nitrogen was coming from septic tanks in that system.
“We're finding the same thing in our studies of estuaries, where you have high densities of septic tanks,” said Lapointe.
“Septic systems provide only primary treatment and are not designed to remove nutrients, like nitrogen or phosphorus, bacteria, viruses, pharmaceuticals or organic wastewater compounds,” he said. “When you look at residential areas close to septic tanks versus natural areas, every nutrient we looked at was higher near the septic tanks.”
According to Lapointe, many people think leaking septic tanks are the problem - but he says septic tanks are designed to leak.
“They have two basic components: they have a tank that holds the solids and they have a drain field that the liquid effluent from that tank flows to, to percolate down through the soil,” he explained. “One of the problems is that those contaminants travel down through the soil. They’re not treated adequately and reach the groundwater, and ultimately surface waters.”
To make matters worse, soil in Florida is particularly unsuitable for septic systems. Lapointe said the state’s sandy, porous soils “allow for rapid percelation of the effluent through the soil, into the groundwater.”
On top of that, Florida’s soil has very low organic content, preventing the process of denitrification, or the removal of nitrogen, by bacteria.
Another problem is the high water tables in the state. Ground water rises and falls from the wet to dry season in Florida. Lapointe said state code requires a minimum of two feet of separation from the bottom of a septic system’s drain field to the seasonally high water table. And, he said, a minimum of two feet is needed for the installation of the tank and drain field, “so you need about four feet from ground service to the seasonally high water table.”
But a recent study conducted in Charlotte County found that 71 percent of septic systems there didn’t meet those requirements.
“This is a real problem for the proper functioning of a septic tank,” he said. “EPA calls for, actually, three to four feet of separation. So, we’re getting very little treatment of this waste effluent moving through the soils in many parts of Florida.”
“As we see more human use and production of nitrogen, we’re seeing an expansion of eutrophication - a buildup of organic matter from these algae blooms,” said Lapointe. “We define these harmful algae blooms as either phytoplankton - single celled algae like the red tide or the blue green algae - or macroalgae - larger seaweeds - that can cause harm directly or indirectly by excessive biomass.”
“They can cause mass mortalities of wild and farmed shellfish, human illness due to toxins and death of marine mammals and seabirds,” he went on to say. “And, ultimately, the alteration of marine ecosystems forming dead zones that are devoid of oxygen.”
Lapointe says this nitrogen problem has expanded globally over the past five decades, resulting in more harmful algal blooms, more areas affected, higher economic costs and more public health impacts.
In fact, during the summer of 2018, both the east and west coasts of Florida saw record algae blooms.
But algal blooms aren’t the only outcome of higher nitrogen levels. Lapointe said during Hurricane Irma, cities were flooded with raw sewage as septic systems were flooded.
“This just goes to show what the American Society of Civil Engineers concluded in their 2016 study,” he said. “They gave Florida’s wastewater infrastructure a grade point average of “C” and stormwater a “D” and estimated that Florida needs about $18 billion to upgrade their wastewater infrastructure.”
Lapointe said nitrogen emissions could be contributing significantly to climate change as well. “We consider this issue, nitrogen enrichment of the planet, to be one of the strongest, if not the strongest agent of global change, particularly in coastal waters,” he said.
Even though there are more than 3,700 wastewater treatment facilities in the state, roughly 39 percent of Floridians still rely on septic tanks. According to Lapointe, there are more than 2.6 million septic tanks in Florida and all of them are contributing to the excessive nitrogen levels in the state’s waterways.
Many communities have finished septic to sewer projects, leading to significant water quality improvements. Lapointe urged legislators to take a similar approach, but statewide.
“It has to come from the state,” he said emphatically. “We can’t rely on local governments anymore to do this.”
“I think we need a Manhattan Project. We’ve gotta go to war against algae” Lapointe concluded. “You heard the governor. We’re going to fight the blue green algae. We’re going to fight the red tide. We need a focused group within DEP to really build a plan to go to war.”
In his inauguration speech Tuesday, new Republican Governor Ron DeSantis, said the following:
“People want to come to Florida because of its natural beauty. Tourism is not only a pillar of our state’s economy, it helps spread the tax burden to non-Floridians, limiting taxes on our citizens. But this could be in jeopardy if we do not solve our pressing environmental problems. As the great philosopher Yogi Berra remarked: if people don’t want to come nobody is going to stop them.
“For Florida, the quality of our water and environmental surroundings are foundational to our prosperity as a state – it doesn’t just drive tourism; it affects property values, anchors many local economies and is central to our quality of life. The water is part and parcel of Florida’s DNA. Protecting it is the smart thing to do; it’s also the right thing to do.
“I will lead the efforts to save our waterways. We will fight toxic blue-green algae, we will fight discharges from Lake Okeechobee, we will fight red tide, we will fight for our fishermen, we will fight for our beaches, we will fight to restore our Everglades and we will never ever quit, we won’t be cowed and we won’t let the foot draggers stand in our way.”
Following the meeting, Sen. Aaron Bean (R-Fernandina Beach), a member of the Florida Senate Appropriations Subcommittee on Agriculture, Environment and General Government, described the presentation as “eye-opening.”
“That was, I think, pretty devastating evidence that we need to act and do all we can to limit septic systems and to look at where we can build facilities that can handle adequate sewage restoration,” Bean told WJCT.
“Last year the Florida Legislature went the direction of saying we need water storage and that runoff was one of the significant causes of algae blooms,” he said. “Today’s presentation really countered that to say that is an issue, but a very small issue… the vast majority of the problem is the increase of septic tanks.”
“It’s not going to happen overnight but we need to have a long term strategy in Jacksonville, all over Florida, of how we can wean ourselves off of the septic tank system,” said Bean. “It’s a very expensive proposition to remove anybody from a septic system, so we need to look at a program where the state can partner with local communities to give them the resources to go forward on making that conversion.”
A bill filed in the Florida Senate earlier this month would require inspections of septic systems statewide, at least once every five years. It would also require the health department to develop minimum standards and requirements for pumping out or repairing failing systems.
Duval County alone has an estimated 85,000 septic tanks and as many as 10 percent of them may be failing, according to the Florida Department of Health. In 2016, the Jacksonville City Council approved a $30 million deal with JEA to phase out septic tanks over a five-year period.
A video of Lapointe’s full presentation on septic systems and the role they play in algal blooms can be viewed at FLSenate.gov.