Septic Drain Field Failure in Georgia: Signs, Causes, Next Steps
How can I tell if my septic drain field is failing, and what should I do about it in Georgia?
Short answer
A failing drain field usually shows up as soggy or smelly ground over the field, or as slow drains and backups, often after years of solids, extra water, roots or compaction. Cut water use, keep people off wet spots, skip additives and call a DPH-certified septic contractor; in Georgia, any repair needs a county environmental health permit and inspection.
On this page
The drain field is the part of a septic system you never see: buried trenches where the liquid leaving the tank soaks into the soil. When the field stops taking that liquid, the trouble shows up in one of two places, as soggy, smelly ground in the yard or as slow drains and backups in the house, and it rarely fixes itself.
This guide covers how a field works, the warning signs, the usual causes and what to do first, plus Georgia's rules on repair permits and who may do the work.
How a drain field works
EPA describes the drain field as a shallow, covered excavation in unsaturated soil. Effluent, the liquid from the tank, flows into it through perforated pipes or chambers, and the soil treats and disperses it, removing harmful bacteria, viruses and nutrients as it percolates down (EPA). Georgia's rules call it an absorption field (Rule 511-3-1-.02, reprinted in DPH's manual).
The tank's main job, the manual explains, is to protect the field from solids, which can quickly clog the pores in the soil.
Some clogging is built in. DPH's manual explains that where effluent meets the soil, solids, bacteria and slime build up a layer that improves treatment but slows the flow. EPA calls it the biomat and says that once a field is more than 25 to 30 years old, it can thicken enough to cause ponding, sewage at the surface or backups into the house (EPA FAQ). The manual calls this slow decline "creeping failure, or death by old age and/or lack of proper maintenance."
Signs your drain field is failing
EPA lists these among the common signs of a failing septic system (EPA):
- water and sewage backing up into toilets, tubs or sinks;
- slow drains and gurgling in the plumbing;
- standing water or damp spots near or over the tank or drain field;
- sewage odors around the tank or field;
- bright green, spongy grass over the field, even in dry weather;
- high levels of nitrates or coliform bacteria in a drinking water well.
The same page says soft, wet or spongy soil around the field when there hasn't been much rain is a good indication of failure. DPH's manual describes the two ways a field gives out: untreated effluent surfaces, causing odors and a health hazard, or water ponds underground until the tank overfills and the drains in the house slow, stop and back up.
Have the tank checked before anyone condemns the field. Georgia requires an approved filter on the tank's outlet (Rule 511-3-1-.05, reprinted in the manual), EPA notes such filters may need frequent maintenance, and EPA's inspection checklist covers the filter and signs of backup inside the tank.
What usually causes failure
| Cause | What it does to the field |
|---|---|
| Too much water | Leaks, running toilets and heavy water use can flood the field, sending sewage to the surface or back into the house |
| Solids from the tank | Skipped pumping, or broken baffles and tees, let solids wash into the field and clog the soil; a garbage disposal adds solids |
| Roots | Tree and shrub roots can ensnarl and damage drain field pipes |
| Weight and paving | Vehicles and heavy equipment compact the soil and can damage pipes; concrete or asphalt cuts off oxygen the soil needs |
| High water | Seasonal high groundwater and stormwater flooding |
| Additives and chemicals | DPH counts heavy use of chemical additives as a form of user abuse |
| Poor site, design or installation | Very slowly permeable soil, shallow rock, poor installation or a system too small for the household |
Table sources: DPH's manual (Sections C and L), EPA's FAQ and EPA's overview.
The manual singles out construction equipment on wet, high-clay soils, and Georgia's rule voids the county's approval of a system if later grading, filling, landscaping or construction may harm it (Rule 511-3-1-.03). For what shouldn't go down the drain, see what not to flush or pour.
What to do first
- Keep people and pets away from wet spots. EPA calls sewage surfacing from a failed field a direct public health hazard, warns that children and pets can be exposed unknowingly, and says anyone exposed should contact a health professional. If sewage is coming up inside, follow what to do in a sewer backup.
- Use less water right away. Fix running toilets and leaks, spread laundry over the week, and go easy on the garbage disposal.
- Stay off the field. Don't park or drive on it, and don't dig, regrade or pile soil on it.
- Skip the additives. DPH's advisory says additives don't help septic systems and can harm them: biological products can break solids into fine particles that flow into the drain field and clog it, and any early improvement is short-lived (DPH). Georgia's rule also bans strong bases, acids and organic solvents in septic systems (Rule 511-3-1-.17, reprinted in the manual).
- Call a DPH-certified septic contractor to diagnose it. EPA's inspection checklist includes opening the tanks, checking the filter and distribution box, and possibly running a camera through the pipes or digging into parts of the field to look for ponding. Ask for the findings in writing.
- Get your county file. DPH sends septic record requests to county environmental health offices (DPH); the septic or sewer guide explains what to ask for. The manual adds that counties are routinely asked to evaluate how existing systems are performing.
Don't open the tank or lean into it. The manual warns that gases in a septic tank can be toxic and explosive and can kill, and advises that no one enter a tank without proper protective equipment.
Why Georgia requires a permit for repairs
Georgia's rule bars using a system in a way that lets effluent seep or discharge onto the ground surface, into a ditch or storm drain, or into groundwater (Rule 511-3-1-.17), so a surfacing field has to be fixed. The rule is just as direct about the fix: "Repairs, replacement, or additions to existing systems must be permitted and inspected" (Rule 511-3-1-.03). Permits come from the county health department, whose certified inspectors evaluate sites and issue repair permits (DPH manual, Section N).
What a permit takes varies by health district. In Gwinnett, Newton and Rockdale counties, for example, GNR Public Health's repair application asks whether sewage is backing up in the house or surfacing in the yard and when the tank was last pumped. It requires a Level 3 soil report from a certified soil classifier unless an approved one is on file, may require an engineered site plan for a difficult lot, and asks for 10 working days to review the plans and visit the site (GNR Public Health).
The fix depends on what the inspection finds. EPA notes that a field clogged by solids may need to be replaced entirely, and DPH's manual notes that mound systems have been built successfully over failing in-ground fields. Two more rules can shape the outcome:
- Public sewer nearby. When an existing system fails and public sewer is available, the rule calls for immediate connection. A failing home system can be exempted if its repair or replacement meets DPH's manual and the county board of health finds enough area and usable soil (Rule 511-3-1-.03). The septic or sewer guide covers the 200-foot rule, and the local directory shows who provides sewer in metro Atlanta.
- Hardship. The county board of health may grant variances in cases of hardship where existing systems are malfunctioning (Rule 511-3-1-.17).
Who can do the work
Georgia requires septic tank contractors to be certified by DPH, with certification renewed every two years (Rule 511-3-1-.16, reprinted in the manual). The manual defines a certified septic tank installer as someone who installs, repairs or modifies on-site systems, and says installers must work for a DPH-certified septic tank company.
- Start with DPH's lists. The onsite sewage page links lists of certified installers and certified pumpers by county, plus a list of septic contractors and companies DPH has disciplined (DPH).
- Ask who handles the permit. GNR's application lets the contractor you choose act as your agent in applying for and picking up a repair permit.
- Pumping is a separate certification. The septic tank pumping guide covers pumpers and what a proper pump-out includes.
Next step
Cut water use today and keep everyone off wet ground. Then have a DPH-certified septic contractor diagnose the problem, and make sure the county issues a repair permit before any repair work starts. This guide is general information, not legal advice; your county environmental health office can tell you what applies to your property.
Sources
- Georgia Secretary of State (Rules and Regulations of the State of Georgia): Rule 511-3-1-.03 General Requirements for On-Site Sewage Management Systems
- Georgia Department of Public Health: Manual for On-Site Sewage Management Systems
- Georgia Department of Public Health: Onsite Sewage
- Georgia Department of Public Health: Don't Flush Your Money Down the Drain: Additives and Your On-site Sewage Management System
- GNR Public Health: Residential Septic System Permit Application and Repair Permitting Requirements
- U.S. Environmental Protection Agency: How Septic Systems Work
- U.S. Environmental Protection Agency: Resolving Septic System Malfunctions
- U.S. Environmental Protection Agency: Frequent Questions on Septic Systems
Guides that pick up where this one stops.
Septic Tank Pumping in Georgia: How Often and What to Expect
How often to pump a septic tank in Georgia, who may legally do it, what a proper pump-out includes, and the records and warning signs worth tracking.
Septic or Sewer? How to Tell What Your Georgia Home Has
How to tell if a Georgia home is on septic or public sewer: check the bill, ask county environmental health for records, and see what changes for backups.
Sewer Backup in Your House: What to Do, Step by Step
What to do when sewage backs up into a Georgia home: the first steps, who to call, how to clean up safely, and when to hire a professional cleanup crew.