A bowfin swims among a forest of algae in Blue Spring. Scientists say too much nitrogen in the water flowing from the aquifer is promoting the algae growth. Photo provided by Joe Cruz, Deltona.

Septic tanks leak nitrogen into Florida’s springs

Once pristine waters are slowly being choked by high nitrogen levels brought on by septic systems


If finding out what’s causing the demise of Florida’s springs worked like a TV crime show, a researcher could pull a cup of water from any one of Florida’s springs and within minutes pinpoint the source of contamination.

But springs restoration isn’t TV science. Pinpointing the source of the troubles is “not like CSI,” said Tom Frick, director of environmental assessment and restoration for the Florida Department of Environmental Protection. “We don’t have that technology yet.”

Long-time Floridians mourn for the springs of their youth, with crystal clear water, abundant eel grass, fish and crustaceans swimming in the springs. Today, the springs are often clouded, plants are sparse or covered with green slimy algae, and there are fewer fish and other marine life.

In 2016, the state Legislature passed the Florida Springs and Aquifer Protection Act, requiring DEP to figure out what was causing harm to Florida’s 13 “outstanding Florida springs” and come up with plans to begin reversing the damage. The three major springs in western Volusia County were on the list: Blue Spring, Gemini Springs and DeLeon Springs.

The DEP knew going in that nitrogen was the biggest culprit in the decline of Florida’s springs. Even though the springs still hold stunning beauty for newcomers seeing them for the first time, nitrogen levels have been increasing for years, feeding algae blooms that coat plants and rocks in the springs with green slime, upsetting the ecosystems. The challenge now is determine sources of the nitrogen and do something about it.

To develop the required basin management action plans — known as BMAPS — the department used a computer model fed with information such as population and land use activities around the springs to pinpoint the sources of nitrogen. Within each spring basin, a smaller target area was identified as a “priority focus area,” where restoration activities will be focused.

[LEARN MORE: Click here to see if your home is in a spring priority focus area]

In the 108-square mile basin for Blue Spring in Orange City, the department concluded the primary cause of the nitrogen — 54 percent — is coming from human wastewater flowing from more than 23,000 densely clustered septic tank systems in DeLand, DeBary, Deltona and Orange City.

“Septic tanks were never designed for that kind of density,” said Clay Henderson, executive director of Stetson University’s Institute of Water and Environmental Resilience. “We know now for certain more than half the nutrients in Blue Spring are caused by septic tanks and it should be no surprise because of the high concentration of tanks.”

Although other contaminants, such as artificial sweeteners and acetominophen, also make their way into spring water, they aren’t impacting the springs like nitrogen, Frick said. “You may see trace amounts of some of those in our springs, but we haven’t seen them at an acute or chronic level.”

Less is known about the impact of pesticides and herbicides used on lawns and sprayed of aquatic weeds.

At Gemini Springs in DeBary, the study blamed lawn fertilizers for 46 percent of the nitrogen and septic tanks for 41 percent in the 27,290-acre spring basin. Within the smaller 3,096-acre priority focus area that covers much of the southern half of DeBary, 49 percent of the nitrogen comes from roughly 2,334 septic systems.

In more rural DeLeon Springs, the department concluded agriculture-related uses were the biggest nitrogen contributor, with septic tanks contributing an estimated 14 percent of the nitrogen.

Other nitrogen sources identified in the plans include fertilizers on golf courses and farms, storm water runoff and the disposal of sludge and wastewater.

Springs action plans

The basin management plans, with their proposed projects to remove nitrogen and five-year incremental goals over the next 20 years, were adopted last summer. The plans encountered a lot of back and forth among environmental groups, local governments and industry experts, who described them as rushed and without complete information.

Some still say the plans won’t do enough to clean up the springs, which flow from the aquifer that provides most of Florida’s drinking water. Five of the 13 action plans approved last year, including the one for Blue Spring, are on hold pending legal challenges.

The Blue Spring plan is scheduled for administrative hearing in September. The Save the Manatee Club filed the challenge against it, arguing the plan doesn’t go far enough to remove nitrogen and protect the manatees that seek refuge in the spring from the colder St. Johns River in the winter.

The dozens of projects listed in the action plans, ranging in complexity and cost, don’t all have price tags yet, but are expected to cost hundreds of millions of dollars. They range from storm water improvements and wastewater treatment plant improvements to consumer education.

The most complex and expensive issue will be addressing the proliferation of septic tanks, with requirements for the conversion of thousands of septic tanks to more advanced treatment technologies or to municipal sewers.

Septic tank remediation plans are required under the Florida Springs and Aquifer Protection Act any time septic tanks are blamed for at least 20 percent of the pollution in a spring basin.

“It’s not a matter of trying to get rid of every septic tank,” said Mike Ulrich, Volusia County’s utilities director. “The real challenge is to get rid of as few as possible and meet the standards we need to meet at the least expensive cost.”


The Blue Spring action plan sets a goal of removing 61,653 pounds of the nitrogen flowing to Blue Spring, with a reduction of 18,496 pounds in the first five years.

Because the basin is so large, every local government in West Volusia will be required to do something, said Ulrich. The DEP and the water management district will also need to take action. “But just what that is or what the best projects are, still needs to be mapped out,” he said.

Anticipating that new rules were coming, Volusia County began working years ago with other local utilities to improve treatment of wastewater and storm water to reduce nitrogen and other contaminants. The county revamped its large wastewater treatment plant in northern DeBary, expanding it and converting it to an advanced treatment system.

[READ MORE: DeBary water treatment plant]

The multi-million dollar project means the plant will have the capacity to provide sewer services for homes that will need to convert to sewer. It also is removing more nitrogen from the wastewater treated at the plant. The county has closed one smaller treatment plant and will close another, sending all the wastewater to the DeBary plant. The project is jointly funded by springs protection grants from the St. Johns River Water Management District and the DEP.

Deltona also made advances to its wastewater treatment that will help remove nitrogen and other contaminants.

Improved treatment methods are the most cost-effective way to achieve big reductions in nitrogen, Ulrich said. Thanks to the upgrades at the DeBary plant, the county is ahead of its 5-year goal in the action plan for reducing nitrogen. The county also has stepped up efforts to educate homeowners on fertilizer use.

But all of those steps alone will not be enough to clean up the springs, Ulrich said. “The big elephant in the room is septic tanks.”

In DeBary, hundreds of homes with septic tanks sit upslope from Gemini Springs, shown on the bottom left. A springs action plan approved by the state last year lists projects to try to convert many of the homes to more advanced treatment systems or city sewers to try to improve the quality of water flowing from Gemini Springs. Photo provided by Volusia County Property Appraiser's office.

“They’re part of the problem”

Casey Fitzgerald, Springs Protection Initiative director for the Management District, calls it a “difficult political issue for local elected officials.”

“In general, folks really like their septic tanks,” Fitzgerald said. “They don’t recognize the fact they’re part of the problem. It takes an educational effort and political fortitude to move forward with these projects.”

For now, the parts of the action plans addressing what owners of existing septic tanks will be required to do are on hold. The clean-up plans for Gemini Springs and DeLeon Springs became effective in January. But parts of each are delayed while local and state officials develop the rules and information to put them into action, including where necessary funding will come from.

Other plans are moving forward. Any builder of a new single-family home on a lot less than one acre in size in DeLeon Springs or DeBary now is required to install a nitrogen-removing septic tank with added features that provide enhanced treatment of the wastewater or hook up to sewer if available. Such tanks require individual site engineering.

To the frustration of local officials, because the Blue Spring plan is tied up in the administrative challenge, the Florida Department of Health says it must continue allowing new septic tanks to be installed in that spring’s basin.

Once the springs action plans are fully in effect, requirements will include a combination of replacing or enhancing some traditional septic tanks with more advanced and costly treatment systems, and removing other septic tanks and hooking those homes up to municipal sewers in Deltona, DeBary, Orange City and DeLand.

“We will eventually get to the point where the existing systems will be required to be replaced with upgraded systems,” said the DEP’s Frick.

Property owners will be required to add nitrogen-enhancing features to their tanks or install one of the more expensive nitrogen-removing tanks, unless sewer will be available within that neighborhood within five years. If sewer will be available within five years, homeowners will be allowed to install a less-expensive conventional septic tank as a temporary measure until sewers arrive in the neighborhood. Then connection would be required.

Both solutions are costly. Estimates range between $12,000 and $20,000 per home for new advanced septic tanks, and up to $25,000 per home to lay new wastewater lines and hook up a home. That includes the utility’s cost of $15,000 to $20,000 to lay the lines, and the $5,000 cost of hooking up a home to sewer.

Before enforcement starts, key questions must be answered about where and when sewers will be expanded in the neighborhoods that are the worst offenders.

To answer that question, the DEP has contracted with Volusia County to do 20-year sewer feasibility studies for the Gemini Springs and DeLeon Springs basins. The county also will eventually complete a sewer feasibility study for Blue Spring, he said. But it was easier to start with the other two because they are smaller and don’t include several different governments.

The feasibility studies will help homeowners know when or if their neighborhood might get sewers and will help local governments determine where to get the “better bang for the buck” when it comes to converting septic tanks to sewer, said Frick. “The most important thing is that homeowners know and have knowledge of where things are going.

Addressing the tanks will raise “tough questions regarding equity and fairness” when deciding which neighborhoods must replace their tanks and who will share those costs, said Ulrich and other officials.

The DEP has been asked to forward all of the information about the costs to convert neighborhoods and the burden to homeowners to state legislators, said Frick. Additional state-funding is supposed to be developed to help cover the cost of upgrades, but those details haven’t yet been resolved.

New tanks still being developed

Officials with the state health department are still refining their septic tank permitting rules and are still working with the septic industry and university researchers to develop additional types of nitrogen-reducing tanks. The department declined to make one of its experts available for an interview, but stated 23 types of nitrogen-removing systems are approved for use in Florida. Statewide, a total of 12,000 nitrogen-reducing systems have been installed.

The enhancements to existing septic tanks and newer nitrogen-removing septic tanks already are used in areas of Volusia County where installers are unable to place the tank in a yard with the required two feet of soil between the bottom of the drain field and the top of the water table. The tanks provide additional treatment by using a small electrical pump to aerate the contents of a secondary compartment in the tank. Some also use additional filters.

When household wastewater settles into one of those septic tanks, the liquid flows into a second compartment where oxygen flowing into the septic tank provides aerobic treatment and removes some of the nitrogen. A portion of that partially treated water flows out to the drain field, and the rest cycles back into the septic tank for another round of treatment, said Anthony Pesare, owner of Tri-County Septic Service in Orange City. Homeowners also can put in a system that pumps the water from the drain field through a drip irrigation system in the yard, providing another layer of treatment.

The water flowing out through the irrigation would be similar to the reclaimed water distributed by utilities, Pesare said.

Estimates of how much the new systems cost homeowners can vary, but the cost is more than double the roughly $6,000 for a traditional tank and ranges up to $20,000 or more. Each system has to be engineered based on the individual lot, and requires annual maintenance and inspections.

As a less expensive alternative, state health officials wrote rules for a type of treatment called in-ground nutrient reduction, which are basically layers of wood chips beneath the drain field that help trigger the treatment that takes nitrogen out of the water.

But Ronnie Mills, a DeLand septic contractor and owner of Joe Mills Septic Tank Service, said the lower-cost wood chip system isn’t available locally at this point. A legal challenge was filed over the patent for the liner the wood chip septic system uses in the drain field.

Although some in the industry have questioned the effectiveness of the wood chips, the department is “pretty confident in the data they’ve collected,” said Frick. “We’ve seen these systems work, and we’re confident that they will reduce nitrogen.”

Prior to July 2018, only a half-dozen types of advanced treatment septic systems were allowed. Health department officials are working to expand the number of allowed septic systems that remove nitrogen, Frick said.

“Everyone is working on perfecting a nitrogen-reduction system,” said Harry Wild, an engineer who works on septic systems locally. “I expect to see more and more because that’s where a lot of the manufacturing companies are putting emphasis.”

Spring basin facts

Blue Spring, Orange City

Basin size: 108 square miles, or 69,120 acres

Priority focus area: 44,302 acres

Number of septic tanks in priority focus area: More than 26,000

Where does the nitrogen come from in the spring basin?
• 54% septic tanks
• 22% turf grass fertilizers
• 5% atmospheric deposition
• 4% Sports turf fertilizer
• 8% Wastewater treatment
• 2% Farm fertilizer
• 4% Reuse
• 1% livestock waste


Gemini Springs, DeBary

Basin size: 27,290 acres

Priority focus area: 3,096 acres

Number of septic tanks in priority focus area: 2,334

Where does the nitrogen come from in the basin?
• 41% septic tanks
• 46% turf grass fertilizers
• 4% atmospheric deposition
• 4% sports turf fertilizer
• 3% wastewater treatment
• 1% farm fertilizer


DeLeon Springs, DeLeon Springs

Basin size: 65,392 acres

Priority focus area: 24,437 acres

Number of septic tanks in priority focus area: 3,892

Where does the nitrogen come from in the basin?
• 52.3% farm fertilizer
• 18.9% turf grass fertilizer
• 14% septic tanks
• 8.39% livestock waste
• 5.93% atmospheric deposition
• .1% sports turf fertilizer
• .38% wastewater treatment

Source: Florida Department of Environmental Protection, basin management action plans

About This Series

DAY ONE: Hundreds of thousands of septic tanks leak nitrogen into Florida's water supplies, helping fuel algae blooms.

DAY TWO: Restoring water quality in the area's springs will require removing or upgrading thousands of septic systems.

DAY THREE: Deltona has more than 23,000 septic tanks. "No forced sewers" campaign is colliding with Blue Spring restoration.

DAY FOUR: Cities on the east side of Volusia grapple with septic tanks along Mosquito Lagoon and the Halifax and Indian rivers and the damage they may be causing.

DAY FIVE: Paying to convert septic tanks to sewer is no easy — or cheap — task.