A conventional septic system is composed of a septic tank and a drainfield, where most of the wastewater treatment takes place. Image: US EPA
Why do you need to maintain a septic system?
Conventional septic systems are made up of a septic tank (a watertight container buried in the ground) and a drain field, or leach field. In the septic tank, solids settle on the bottom (the sludge layer), and oils and grease float to the top and form a scum layer. The liquid wastewater, which is in the middle layer of the tank, flows out through perforated pipes into the drainfield, where it percolates down through the ground. Most wastewater treatment takes place in the drainfield.
Solids settle to the bottom of a septic tank (sludge), oils and greases float to the top (scum) and wastewater (effluent) flows out of the tank into the drainfield for further treatment. Image: Soil and Water Science Lab, UF GREC.
Although bacteria continually work on breaking down the organic matter in your septic tank, sludge and scum will build up, which is why a system needs to be cleaned out periodically. If not, sludge and scum can flow into the drainfield clogging the pipes and sewage can back up into your house. Overloading the system with water also reduces its ability to work properly by not leaving enough time for material to separate out in the tank, and by flooding the system.
Should you use additives in your septic system?
Septic systems do not need any additives to function properly and treat wastewater. Although there are many commercial microbiological and enzyme additives sold on the market that claim to enhance bacterial populations and reduce the time between septic system pumping, there really isn’t any peer-reviewed scientific literature that shows that these additives are effective in doing what they claim.
In Florida, the Department of Health (DOH) reviews commercially sold additives to ensure that they are safe to use in septic systems. DOH clearly states that although products are approved, it does not mean that this is an endorsement or a product recommendation. Approval simply means that as required by Florida law, the additive doesn’t interfere with septic system function and that when an additive is used, the effluent (wastewater) leaving the septic system meets Florida’s water quality standards. Only products in compliance with this law can be sold or used in septic systems in Florida. You can find a list of approved products and more information regarding additives on the Florida Department of Environmental Protection (FDEP) septic system website. Access the list of products directly here (updated 10/18/2021).
How can you properly care for your septic system?
The best way to keep your system functioning properly is to follow some common-sense practices.
- Only flush human waste and toilet paper down the toilet. Wet wipes do not break down in the septic system even though the packaging labels them as septic-safe!
Be mindful of what you put down sinks and flush down toilets. All drains in your home lead to the septic tank. Image: A. Albertin
- Think at the sink. Avoid pouring oil and fat down the kitchen drain. Avoid excessive use of harsh cleaning products and detergents which can affect the microbes in your septic tank (regular weekly cleaning is fine). Prescription drugs and antibiotics should never be flushed down the toilet.
- Limit your use of the garbage disposal. Disposals add organic matter and additional water to your septic system, which results in the need for more frequent pumping.
- Take care at the surface of your tank and drainfield. Don’t drive vehicles or heavy equipment over the system. Avoid planting trees or shrubs with deep roots that could disrupt the system or plug pipes.
- Conserve water. Reduce the amount of water pumped into your septic tank through water conservation practices like (1) repairing leaky faucets, toilets, and pipes, (2) installing, low-flush toilets, low-flow showerheads and faucet aerators, and (3) only running the washing machine and dishwasher when full.
- Have your septic system pumped by a certified professional. The general rule of thumb is every 3-5 years, but it will depend on household size, the size of your septic tank, how much wastewater you produce and what you flush down your toilet.
Even when conventional septic systems are well maintained, they are still a source of nutrients, particularly nitrogen, to groundwater. They were designed from a public health perspective to remove pathogens, not nutrients.
For more information on septic systems, visit the UF/IFAS septic system website and FDEP’s septic system website.
Jackson Blue Springs discharging from the Floridan Aquifer. Jackson County, FL. Image: Doug Mayo, UF/IFAS Extension.
Florida has one of the largest concentrations of freshwater springs in the world. More than 1000 have been identified statewide, and here in the Florida Panhandle, more than 250 have been found. Not only are they an important source of potable water, springs have enormous recreational and cultural value in our state. There is nothing like taking a cool swim in the crystal-clear waters of these unique, beautiful systems.
How do springs form?
We have so many springs in Florida because of the state’s geology. Florida is underlain by thick layers of limestone (calcium carbonate) and dolomite (calcium magnesium carbonate) that are easily dissolved by rainwater that percolates into the ground. Rainwater is naturally slightly acidic (with a pH of about 5 to 5.6), and as it moves through the limestone and dolomite, it dissolves the rock and forms fissures, conduits, and caves that can store water. In areas where the limestone is close to the surface, sinkholes and springs are common. Springs form when groundwater that is under pressure flows out through natural openings in the ground. Most of our springs are found in North and North-Central Florida, where the limestone and dolomite are found closest to the surface.
Springs are windows to the Floridan Aquifer, which supplies most of Florida’s drinking water. Image: Ichetucknee Blue Hole, A. Albertin.
These thick layers of limestone and dolomite that are below us, with pores, fissures, conduits, and caves that store water, make up the Floridan Aquifer. The Floridan Aquifer includes all of Florida and parts of Georgia, South Carolina, and Alabama. The thickness of the aquifer varies widely, ranging from 250 ft. thick in parts of Georgia, to about 3,000 ft. thick in South Florida. The Floridan is one of the most productive aquifer systems in the world. It provides drinking water to about 11 million Floridians and is recharged by rainfall.
How are springs classified?
Springs are commonly classified by their discharge or flow rate, which is measured in cubic feet or cubic meters per second. First magnitude springs have a flow rate of 100 cubic feet or more per second, 2nd magnitude springs have a rate of 10-100 ft.3/sec., 3rd magnitude flows are 1-10 ft.3/sec. and so on. We have 33 first magnitude springs in the state, and the majority of these are found in state parks. These springs pump out massive amounts of water. A flow rate of 100 ft.3/sec. translates to 65 million gallons per day. Larger springs in Florida supply the base flow for many streams and rivers.
What affects spring flow?
Multiple factors can affect the amount of water that flows from springs. These include the amount of rainfall, size of caverns and conduits that the water is flowing through, water pressure in the aquifer, and the size of the spring’s recharge basin. A recharge basin is the land area that contributes water to the spring – surface water and rainwater that falls on this area can seep into the ground and end up as part of the spring’s discharge. Drought and activities such as groundwater withdrawals through pumping can reduce flow from springs systems.
If you haven’t experienced the beauty of a Florida Spring, there is really nothing quite like it. Here in the panhandle, springs such as Wakulla, Jackson Blue, Pitt, Williford, Morrison, Ponce de Leon, Vortex, and Cypress Springs are some of the areas that offer wonderful recreational opportunities. The Florida Department of Environmental Protection has a ‘springs finder’ web page with an interactive map that can help you locate these and many other springs throughout the state.
Prepare an emergency drinking water supply for your household before a storm hits. Image: Tyler Jones, UF/IFAS.
Storm season is upon us. During a natural disaster, normal drinking water supplies can quickly become contaminated. To be prepared, collect and store a safe drinking water supply for your household before a storm arrives.
How much water should be stored?
- Store enough clean water for everyone in the household to use 1 to 1.5 gallons per day for drinking and personal hygiene (small amounts for things like brushing teeth). Increase this amount if there are children, sick people, and/or nursing mothers in the home. If you have pets, store a quart to a gallon per pet per day, depending on its size.
- Store a minimum 3-day supply of drinking water. If you have the space for it, consider storing up to a two-week supply.
- For example, a four-person household requiring 1.5 gallons per person per day for 3 days would need to store 18 gallons: 4 people × 1.5 gallons per person × 3 days = 18 gallons. Don’t forget to include additional water for pets!
What containers can be used to store drinking water?
Store drinking water in thoroughly washed food-grade safe containers, which include food-grade plastic, glass containers, and enamel-lined metal containers, all with tight-fitting lids. These materials will not transfer harmful chemicals into the water or food they contain.
More specific examples include containers previously used to store beverages, like 2-liter soft drink bottles, juice bottles or containers made specifically to hold drinking water. Avoid plastic milk jugs if possible because they are difficult to clean. If you are going to purchase a container to store water, make sure it is labeled food-grade or food-safe.
As an extra safety measure, sanitize containers with a solution of 1 teaspoon of non-scented household bleach per quart of water (4 teaspoons per gallon of water). Use bleach that contains 5%–9% sodium hypochlorite. Add the solution to the container, close tightly and shake well, making sure that the bleach solution touches all the internal surfaces. Let the container sit for 30 seconds and pour the solution out. You can let the container air dry before use or rinse it thoroughly with clean water.
Best practices when storing drinking water
- Store water away from direct sunlight, in a cool dark place if possible. Heat and light can slowly damage plastic containers and can eventually lead to leaks.
- Make sure caps or lids are tightly secured.
- Store smaller containers in a freezer. You can use them to help keep food cool in the refrigerator if the power goes out during a storm.
- Keep water containers away from toxic substances (such as gasoline, kerosene, or pesticides). Vapors from these substances can penetrate plastic.
- When possible, use water from opened containers in one or two days if they can’t be refrigerated.
- Although properly stored public-supply water should have an indefinite shelf life, replace every 6-12 months for best taste.
More information on preparing an emergency drinking water supply can be found on the CDC website and in the EDIS Publication ‘Preparing and Storing an Emergency Safe Drinking Water Supply‘
Many of Florida’s historic first magnitude springs are classified as nitrogen impaired. Image credit: UF/IFAS Communications
Septic systems are an effective means of treating wastewater when they are properly designed, constructed and maintained. Conventional systems are designed from a public health perspective and have been widely used since the 1940s to remove pathogens and protect human health. About 30% of Florida’s population relies on septic systems, which treat and dispose household wastewater drained from bathrooms, kitchens and laundry machines.
However, septic systems were not designed to remove nutrients. A conventional system removes only about 30 percent of the nitrogen that flows into it. Even a well-maintained system will become a source of nitrogen (particularly nitrate-nitrogen) to the surrounding soil in the drainfield, and may leach to groundwater. Excess nitrogen in Florida’s waterbodies can be a contributing factor to ecological community degradation and increases in algae.
What alternatives are there to conventional septic systems?
Many enhanced nitrogen removal technologies exist, but only those approved by the Florida Department of Health (FDOH) can be installed. Conventional septic systems are made up of a septic tank and a drainfield (or leachfield). Advanced treatment systems add steps to conventional system processes to improve contaminant removal. Types of advanced nitrogen removal technologies available include:
- Aerobic Treatment Units ATUs are made of fiberglass, polyurethane or concrete. Unlike conventional systems, ATUs introduce air into the sewage in the tank using a pump. By aerating waste, the organic matter in the tank is broken down faster than in a conventional system. Effluent from an ATU is discharged into a drainfield for further treatment in the soil, just as with a conventional septic system. ATUs require higher energy input than conventional septic systems to power the aerator, and regular operation and maintenance to sustain performance ATU example from the US EPA
- Performance Based Treatment Systems PBTS are specialized systems designed by professional engineers to meet specific levels of contaminant removal based on site and/or situation requirements. There are many proprietary commercial options available. Designs often include an ATU. Like ATUs, PBTS require higher energy input than conventional septic systems to power pumps, and regular maintenance is needed to sustain performance.
- In-Ground Nitrogen Removing Biofilters INRB are also referred to as modified drainfields. These systems are passive, which means they require no electric aerators or pumps to treat wastewater, and maintenance requirements are lower than those for ATUs and PBTS. INRBs are nitrogen-reducing media layers placed underneath a conventional drainfield.
Ammonium-nitrogen in wastewater leaving the septic tank moves down through the Drainfield Area soil and an additional oxygen-rich zone (Unsaturated Nitrification Soil) to promote conversion into nitrate-nitrogen. Wastewater then passes through a low-oxygen, carbon-rich zone to promote denitrification (Woodchips/Soil Mix Denitrification Media). Denitrification is a process by which specialized bacteria convert nitrate into nitrogen gas that escapes into the atmosphere. This reduces the amount of nitrogen that can leach into groundwater.
FDOH provides comprehensive information about advanced treatment systems and requirements on their product listing and approval requirement web page.
Where are advanced treatment systems required?
The short answer is wherever a septic system remediation plan to protect Florida Springs has been put into place. The 2016 Florida Springs and Aquifer Protection Act was passed to protect 30 ‘Outstanding Florida Springs.’ The majority are historic first magnitude springs, springs with flows of more than 100 cubic ft/second. Twenty-four of these springs are identified as nitrogen impaired by the Florida Department of Environmental Protection.
If septic systems contribute more than 20% of the nitrogen load to the impaired spring, a remediation plan takes effect in specific areas (Priority Focus Areas) that are particularly susceptible to nitrogen pollution. Septic system remediation plans require new development to connect to central sewer where available. If this isn’t an option, new construction on lots of less than 1 acre must include advanced nitrogen-removal technology. In the Panhandle, areas around Wakulla Springs and Jackson Blue Springs have remediation plans.
The best source of information about specific remediation plans and whether or not you live in a Priority Focus Area is FDOH. Contact your local County Department of Health Office to find out if you live in a PFA or if you have questions about septic tank requirements, permitting and approved advanced nitrogen-treatment features for septic systems.
For more information and resources about conventional septic systems and advanced treatment system visit our UF/IFAS Septic Systems website.
Senate Bill 712 ‘The Clean Waterways Act’ was signed into Florida law on June 30, 2020. The purpose of the bill is to better protect Florida’s water resources and focuses on minimizing the impact of known sources of nutrient pollution. These sources include septic systems, wastewater treatment plants, stormwater runoff as well as fertilizer used in agricultural production.
Senate Bill 712 focuses on protecting Florida’s water resources such as Jackson Blue Springs/Merritt’s Mill Pond, pictured here. Credit: Doug Mayo, UF/IFAS.
What major provisions are included in SB 712?
Primary actions required by SB712 were listed in a news release by Governor Desantis’ staff in June 2020 as:
- Regulation of septic systems as a source of nutrients and transfer of oversight from the Florida Department of Health (DOH) to the Florida Department of Environmental Protection (DEP).
- Contingency plans for power outages to minimize discharges of untreated wastewater for all sewage disposal facilities.
- Provision of financial records from all sanitary sewage disposal facilities so that DEP can ensure funds are being allocated to infrastructure upgrades, repairs, and maintenance that prevent systems from falling into states of disrepair.
- Detailed documentation of fertilizer use by agricultural operations to ensure compliance with Best Management Practices (BMPs) and aid in evaluation of their effectiveness.
- Updated stormwater rules and design criteria to improve the performance of stormwater systems statewide to specifically address nutrients.
How does the bill impact septic system regulation?
The transfer of the Onsite Sewage Program (OSP) (commonly known as the septic system program) from DOH to DEP becomes effective on July 1, 2021. So far, DOH and DEP submitted a report to the Governor and Legislature at the end of 2020 with recommendations on how this transfer should take place. They recommend that county DOH employees working in the OSP continue implementing the program as DOH-employees, but that the onsite sewage program office in the State Health Office transfer to DEP and continue working from there. DOH created an OSP Transfer web page where updates and documents related to the transfer are posted.
How does the bill impact agricultural operations?
SB 712 affects all landowners and producers enrolled in the Florida Department of Agriculture and Consumer Services (FDACS) BMP Program. Under this bill:
- Every two years FDACS will make an onsite implementation verification (IV) visit to land enrolled in the BMP program to ensure that BMPs are properly implemented. These visits will be coordinated between the producer and field staff from FDACS Office of Agriculture and Water Policy (OAWP).
- During these visits (and as they have done in the past), field staff will review records that producers are required to keep under the BMP program.
- Field staff will also collect information on nitrogen and phosphorus application. FDACS has created a specific form, the Nutrient Application Record Keeping Form or NARF where producers will record quantities of N and P applied. FDACS field staff will retain a copy of the NARF during the IV visit.
FDACS-OAWP prepared a thorough document with responses to SB 712 Frequently Asked Questions (FAQ’s). It includes responses to questions about site visits, the NARF and record keeping, why FDACS is collecting nutrient records and what will be done with this information. The fertilizer records collected are not public information, and are protected under the public records exemption (Section 403.067 Florida Statutes). For areas that fall under a Basin Management Action Plan (like the Jackson Blue and Wakulla Springs Basins in the Florida Panhandle), FDACS will combine the nitrogen and phosphorus application data from all enrolled properties (total pounds of N and P applied within the BMAP). It will then send the aggregated nutrient application information to FDEP.
Details of how all aspects of SB 712 will be implemented are still being worked out and we should continue to hear more in the coming months.