Septic System Backing Up in Tennessee: What to Do in the First Hour, and Then

Most of what is written about a backed-up septic system is written to sell an emergency call-out, so it is long on urgency and short on order. The order is the useful part. Here it is, with the sources.

First: is it the system, or a drain?

One slow sink is a plumbing problem. A septic failure shows up in more than one place at once, and the EPA's list of "common signs of a failing septic system" is the checklist:

• "Water and sewage from toilets, drains, and sinks backing up into the home's plumbing"
• "Bathtubs, showers, and sinks draining very slowly"
• "Gurgling sounds in the plumbing system"
• "Standing water or damp spots near or over the septic tank or drainfield"
• "Sewage odors around the septic tank or drainfield"
• "Bright green, spongy lush grass over the septic tank or drainfield, even during dry weather"

The lowest fixture in the house backs up first, which is why it is usually a downstairs shower or a basement floor drain, and why the upstairs can seem fine for another day. If the yard signs are present too — the damp patch, the smell, the suspiciously green strip — it is the field, not the tank, and that changes what you are about to pay for.

The first hour

Stop putting water in. Every gallon down the drain now comes back up the lowest one. No laundry, no dishwasher, short showers or none. This is the single most effective thing you can do before anyone arrives, and it costs nothing.

Stay out of it. The EPA's flood guidance applies to a backup too: "avoid contact with the sewage as it may contain harmful pathogens." Keep children and pets off any wet ground over the field. Do not open the tank yourself; the gases in a septic tank are a well-documented way for a homeowner to be killed trying to save a call-out fee.

Make the calls, in this order.

1. A permitted pumper. Emptying the tank relieves the backup immediately and, more importantly, lets someone look inside. Pumpers must hold an annual state permit under Rule 0400-48-01-.20, which expires every 31 December; the listings on this site show the permit number and the date it was last checked. The nearest ones are on the city pages for Columbia, Spring Hill, Franklin, Thompson's Station and Leiper's Fork.
2. The permitting authority, if the pumper says it is more than a full tank. In Maury County that is TDEC's Columbia Environmental Field Office, (931) 380-3371, or the online Septic Service Request portal. In Williamson it is Sewage Disposal Management, (615) 790-5751. The EPA's advice matches: "contact a local septic system service provider, your local health department, or onsite wastewater treatment regulatory agency."
3. A permitted installer, once the repair permit exists. Not before.

Why the permit comes before the excavator

Rule 0400-48-01-.06(1): "No property owner or installer of a subsurface sewage disposal system shall construct, alter, extend or repair" one without a permit, and repair permits are mandatory "when installing tanks (septic or dosing) and/or installing absorption field line in order to correct an existing failure." TDEC's own page says the repair permit is "required before any work on a failing septic system is performed." It is free. An installer who starts digging the same afternoon without one is doing you no favour; the whole picture is in septic repair permits in Tennessee.

One consequence of the rule is good news for owners of older properties. The Commissioner "may allow repairs even if the site doesn't meet certain soil and area requirements," so a lot that could never be permitted for a new system today can still be permitted for repair. That is most of the older housing stock in rural Tennessee.

What the state will do, and will not

It will make you fix it. Rule 0400-48-01-.13: "It is the property owner's responsibility to maintain the system in a safe and sanitary manner," and "should the system malfunction, the Commissioner shall issue, in writing, a maximum thirty (30) day notice to the owner requiring repair, replacement or improvement of the system." Sewage on the surface is not a private matter once a neighbour or an inspector sees it.

It will not fix it for you, and it will not tell you what the fix costs. The state publishes its permit fees and nothing else; the repair itself is priced by the installer, privately. What we can say is the shape of the bill: a full tank is a pump-out; a failed field on the same soil is a repair permit and new field line; a failed field on soil that has changed classification, or was marginal to begin with, is an alternative design and a different bracket entirely. Whether your ground is the marginal kind is on your city's page — Columbia's rates 60% of the surrounding land very limited for an absorption field; Nolensville's rates 91%.

Why it happened

The EPA's causes are unglamorous: "inappropriate design or poor maintenance," systems "installed at sites with inadequate or inappropriate soils, excessive slopes, or high ground water tables," and the one that is genuinely in the owner's hands — "failure to perform routine maintenance can cause solids in the tank to migrate into the drain field" and clog it. The interval that prevents the last one is in how often to pump a septic tank. A field clogged by solids that should have been pumped out three years ago is the most avoidable expensive thing in this whole category.

If you are selling

Tennessee requires disclosure, not inspection, and a known failure is a disclosure. The buyer's inspection letter is a state document that will find it anyway — see septic and the home sale and what a septic inspection costs. Fixing it under a free repair permit before listing is nearly always cheaper than what it does to the price after.