From the Field

What Not to Flush or Pour Down the Drain on Septic

By Ryan Chastain, Licensed Master Plumber Updated November 7, 2026

Your septic tank is not a trash can. A short list of things causes most of the clogged tanks and ruined drain fields Ryan hears about.

Call (706) 669-5727 Text Ryan

Short answer: flush only human waste and toilet paper, and keep grease, wipes and harsh chemicals out of every drain. The tank can only handle what bacteria and soil can break down.

Never flush: wipes (even "flushable" ones), paper towels, feminine products, dental floss, cat litter, coffee grounds, medicine.
Never pour down a drain: cooking grease or oil, paint, solvents, pesticides, antifreeze.
Who it applies to: every home on a septic system, including cabins and rentals with guests who do not know the rules.
Call or text Ryan: when a toilet or drain backs up, or smells like sewage.

What is safe to flush on septic

The EPA's advice is short: flush only human waste and toilet paper. That is it. A septic tank is built to digest those two things, and nothing else breaks down well enough to keep up.

If you own a cabin or a vacation rental, put a small sign above the toilet. Guests do not know your plumbing, and one pack of wipes flushed on a weekend can cause a Monday problem.

What not to flush

According to the EPA, do not flush any of the following:

Cooking grease or oil
Wipes marked flushable or not, and paper towels
Feminine hygiene products and condoms
Dental floss and cigarette butts
Diapers
Coffee grounds and cat litter
Medicines and other pharmaceuticals
Gasoline, oil, pesticides, antifreeze, paint and paint thinner

Wipes are the most common culprit. They do not fall apart like toilet paper does, so they pile up in the tank, snag on pump parts and can clog pipes. The word "flushable" on the package does not make them septic safe.

What not to pour down the drain

The kitchen sink is where most septic trouble starts. Do not pour cooking oil or grease down the drain. Fats, butter, wax, cheese and heavy cream all count. They float to the top of the tank as scum, and some of it can move on and coat the pipes in the drain field.

Also keep out oil-based paints, solvents, pesticides and large amounts of toxic cleaners. Harmful chemicals can reach groundwater, and many North Georgia homes get their drinking water from a well, so what goes into the ground matters to your own water as well.

Already flushed something you should not have?

Do not wait for a backup. Text Ryan what happened. He is a licensed Master Plumber, and he answers his own phone.

Call (706) 669-5727 Text Ryan

Chemical drain cleaners and septic

The EPA recommends avoiding chemical drain openers. Use boiling water or a drain snake instead. Ryan clears drains mechanically for the same reason. Harsh chemicals can harm the pipes and can upset the bacteria your tank depends on.

If a drain will not clear, call or text before reaching for a bottle. Read more on our drain cleaning page.

Water softener discharge and septic

This one is a common question, and the honest answer is that it depends on your system and the softener. Water softeners send backwash water to a drain, and some homeowners route it into the septic tank while others send it elsewhere. We did not find a clear EPA number on this, so we do not give you one here.

What we can tell you is that extra water is a load on a drain field, and the EPA advises spreading water use out. Ask Ryan before you choose where a softener drains. He installs water treatment systems and can look at how yours is set up.

Water use is part of the story too

It is not only what goes down, but how much. The EPA says indoor use in a typical single-family home can reach 70 gallons per person per day. A single leaky or running toilet can add up to 200 gallons a day. Spread laundry across the week, because doing it all in one day can flood the drain field and does not give the tank time to treat waste.

A running toilet is an easy fix. Our post on a running toilet shows what to look at first.

What about septic additives?

You may see products that promise to keep a tank healthy. The EPA says additives are not needed for a septic system to function properly. A regular inspection and pumping schedule does more than a bottle will.

Common Questions

Are flushable wipes safe for septic?

No. The EPA lists non-flushable wipes among things not to flush, and in real homes even wipes sold as flushable pile up in tanks and snag pumps. Put all wipes in the trash.

Can I pour a little grease down the sink if I run hot water?

No. The EPA says not to pour cooking oil or grease down the drain. Hot water only moves it further along, where it cools and coats pipes or the drain field.

Is bleach or cleaning spray okay in small amounts?

Small amounts of household cleaners used as directed are different from large volumes of toxic cleaners. The EPA says to avoid pouring large volumes of toxic cleaners or chemical drain openers down the drain. When in doubt, use less.

What do I do if a toilet will not flush and I have septic?

Stop using water in the house and call or text Ryan. Running more water can push sewage out of a low drain. Our page on a toilet backing up has the first steps.

Does Ryan pump the tank if it is full of wipes?

No, Ryan repairs septic systems and clears blocked drain lines. A septic pumping company empties the tank. If the pipes or parts are damaged, call or text Ryan.