Septic questions, answered for the Holston valley.

Most household septic tanks need pumping every three to five years. A smaller tank, a bigger household, a garbage disposal or a lot of laundry pushes that toward the short end.

A two- or three-bedroom home on a 1,000-gallon tank with a couple of people living in it may go five years. The same tank with a family of five and a disposal might need it every two or three. A lake house that sits empty half the year can go longer. If you don’t know when it was last pumped, it’s worth having it done and starting a record.

We find and uncover the tank lids, pump the sludge and scum out of every compartment into the truck, look at the tank while it’s open, and put the lids back on secure.

While the tank is empty we can see the inlet and outlet, the water level and the condition of the tank itself. That tells you more about the system than the pumping does. A tank that refills from the field side, or a missing outlet baffle, is something you want to know about.

Not always. If we can reach the tank and you’ve told us where the lids are, a pump-out can often be done while you’re away. Talk it over when you call.

It does help to be there the first time, or to leave clear notes: where the tank is, whether the lids are buried, and where the dogs are. Keep pets inside while the lids are open.

A healthy tank doesn’t need them. The bacteria that break down waste arrive with every flush, and no additive replaces pumping out the solids that build up.

Some additives can even stir up the sludge and push it out toward the drain field. Save the money and put it toward pumping on schedule.

Wipes (even “flushable” ones), grease and cooking oil, paper towels, feminine products, cat litter, medicines, paint and harsh chemicals.

Wipes and grease are the two we see most. Wipes don’t break down and catch in the line and the outlet; grease cools into a cap on top of the tank and can be carried into the field. A little household bleach or cleaner is fine. Gallons of anything are not.

It doesn’t ruin one, but it adds solids to the tank and usually means pumping more often. Scraping plates into the trash is kinder to the system.

Slow drains all over the house, gurgling pipes, sewage smell outside, wet or extra-green ground over the drain field, and sewage backing up into the lowest drain.

One slow sink is usually a clog in that sink. When everything slows at once, the trouble is past the house: the line to the tank, the tank itself, or the drain field. The sooner it’s looked at, the more likely it is to be a simple fix like a pump-out or a cleared line.

Stop using water right away, keep people and pets out of the area, and call. Sewage is a health hazard, so don’t wade through it or try to clean it up bare-handed.

Every flush, shower and load of laundry adds to the backup, so turn off the washing machine and dishwasher too. Don’t open the septic tank yourself. When we get there, we’ll find out whether it’s the house line, the tank, or something further out.

No. Never enter a septic tank or lean into an open one. Septic gases (hydrogen sulfide and methane) and the lack of oxygen can kill in minutes, and people have died trying to rescue someone who went in.

Keep lids secure and in good shape so children and pets can’t fall in. If a lid is cracked, missing or sinking, cover the area and call; that’s a repair worth making right away.

Heavy rain fills the soil around the drain field, so the field can’t take water as fast and odors rise. If it fades in a day or two it may just be wet ground; if it lingers, the tank may be full or the field struggling.

Our ridge-and-valley soils are often thin over rock or tight with clay, so they saturate quickly. Keep roof downspouts and driveway runoff away from the field, and have the tank checked if the smell keeps coming back.

It can be. Gurgling after a flush often means air is being pushed back through the plumbing because the line or tank isn’t draining freely.

It can also be a blocked plumbing vent on the roof. If several drains gurgle and run slow together, start with the septic side: when was the tank last pumped?

The Tennessee Department of Environment and Conservation (TDEC), Division of Water Resources. Hawkins County is handled by TDEC’s Johnson City field office; Hamblen and Grainger counties by the Knoxville field office.

None of the three is a “contract county.” A handful of Tennessee counties, including nearby Jefferson, Knox and Sevier, run their own septic programs under contract with the state; in those, you deal with the county. Everywhere else, including Mooresburg, Rogersville, Morristown and Bean Station, it’s TDEC.

Yes. TDEC requires a permit to construct, modify or repair a septic system. Pumping a tank doesn’t need one, but replacing a drain field or changing the system does.

A TDEC environmental specialist looks at the site and the soil, and the work is inspected before it’s covered. Ask whoever does the work to handle the permit, and keep a copy with your house records.

Yes. Anyone who pumps and hauls septage in Tennessee needs a septic tank pumping permit from TDEC. Grace Septic LLC holds TDEC pumper permit #951, listed under Hawkins County.

You can check any pumper on TDEC’s list of active septic installers and pumpers on tn.gov. It’s a fair question to ask anyone who comes to pump your tank.

Start with TDEC. It keeps septic permit records and has an online search for permits; the Johnson City or Knoxville field office can help if your record isn’t online.

Older homes may have no record at all. In that case the tank is found the old-fashioned way: following the line out from the house and probing for the lid. Once it’s found, a sketch with measurements from the house saves everyone time next visit.

Check that they hold a TDEC septic pumping permit, ask what the price includes, and read recent reviews. A good company explains what it saw in your tank, not just what it pumped.

Ask whether the price covers finding and digging up the lids, how many compartments they’ll pump, and whether they look at the baffles. If a repair is suggested, ask what’s wrong, why, and whether it needs a TDEC permit.

Because the ground here is the Valley and Ridge: long parallel ridges and valleys of folded limestone, dolomite and shale. Soils are often shallow over rock, rocky or cherty, or tight red clay, and the limestone underneath is full of cracks, sinkholes and springs.

A drain field needs enough good soil between the pipe and the rock to clean the water before it reaches groundwater. Where the soil is thin, systems have to be sized and placed carefully, and a field that’s overloaded has less margin before it fails.

Limestone dissolves over time, leaving cracks, caves and sinkholes. Where soil is thin over that rock, poorly treated water can reach springs and wells quickly, so the soil above it has to do the cleaning.

That’s why TDEC looks closely at soil depth when it permits a system, why you never route a drain field toward a sinkhole, and why keeping the tank pumped (so solids don’t clog the field) matters so much here.

Many East Tennessee homes have a conventional tank and gravel trenches. Where soil is too shallow or tight, TDEC may require an alternative design, such as a low-pressure system with a pump that spreads effluent over a larger area.

If your system has a pump tank, an alarm or a control panel, it needs a little more attention than a gravity system. Don’t open the control panel yourself, and call when the alarm sounds.

The basics are the same, but lake lots are often steep, rocky and close to the water, so the system has less room for error. Keep the tank pumped on schedule, and keep runoff and heavy loads off the drain field.

Cherokee Lake is a TVA reservoir, and the shoreline is managed by TVA. Septic tanks and drain fields belong on your own lot, permitted by TDEC; work on or near the shoreline may also need TVA approval. A lake house used mostly on weekends still needs pumping, especially if it’s busy all summer.

Yes. Roots seek out the water in septic lines and drain fields and can clog or crack them. Willows, maples and other thirsty trees planted near the field are the usual culprits.

Keep new trees well away from the tank and field. If roots are already in the house line, snaking the clean-out clears them for now, and pumping on schedule keeps the tank from overflowing into the field.

No. Vehicles, livestock, sheds, pools and driveways compact the soil and crush pipes, and a crushed field can’t be pumped back to health.

Grass is the right cover. Mow it, keep it, and keep heavy traffic off it.

It depends on the size of the trap and how much grease the kitchen produces. A common rule is to pump it before the grease and solids fill a quarter of its depth; for many busy kitchens that means every one to three months.

Your sewer utility or local code may set a specific frequency, so check your permit or ask your utility. A trap that’s pumped too rarely stops catching grease, and that grease ends up in the sewer line.

Your local sewer utility and the plumbing code it enforces. Utilities set fats, oils and grease (FOG) rules for food businesses on public sewer, including trap sizing, inspections and pumping records.

Rules differ from one utility to the next, so start with the utility that sends your sewer bill. Keep every pumping receipt; inspectors usually ask to see them.

A grease trap catches fats, oils and grease from a kitchen before they reach the sewer or septic tank. A septic tank treats all the wastewater from a building. They’re pumped separately, and a kitchen on septic often has both.

If a restaurant or church kitchen is on a septic system, a working grease trap protects the septic tank and the drain field from grease, which is one of the fastest ways to clog a field.

Yes. Church fellowship halls, camps and some large home kitchens have grease traps or interceptors, especially when they cook for crowds. They need pumping like any other trap.

A capped pipe sticking up from the line between your house and the septic tank. It gives access to snake the line when it clogs, without digging.

Most homes have one near the foundation and some have another closer to the tank. Know where yours is. Snaking from the clean-out clears wipes, roots and grease in the house line, which is often the real cause of a “septic backup.”

If the clean-out near the house is full of water, the blockage is further out: the line near the tank, or the tank itself. If it’s dry, the clog is between the house and the clean-out.

Don’t open the septic tank to check. Call, and we’ll snake the line or pump the tank as the case needs.

Risers are short pipes or collars that bring the tank lids up to ground level, so the tank can be found and opened without digging. They save time and digging on every future pump-out.

Risers must have secure, child-resistant lids that can’t be lifted by a child or slide off. A loose or cracked lid over an open tank is dangerous.

Tennessee doesn’t have a statewide rule requiring a septic inspection at every sale. Buyers and lenders often ask for one anyway, and it’s wise.

For a buyer, a pump-out with a look inside the tank, plus TDEC’s permit record for the property, tells you a lot about what you’re buying. For a seller, having the tank pumped and records ready before listing avoids surprises.

Ask when the tank was last pumped and by whom, how big it is and where it is, whether there’s a TDEC permit on file, and whether there have been backups or repairs.

Walk the drain field area for soggy spots or smells. On a lake or rocky lot, ask what kind of system it is; a pump system with an alarm needs a different kind of care than a gravity system.