

Why Is Sewage Backing Up Into My Bathtub?

John Turpin is our resident home service repair expert here at Service Direct. He’s got the knowledge and experience to help homeowners like you make sense of most home repair issues. And with Service Direct, we connect you with top-tier service professionals to help with any repairs needed.
Learn What to Do When Sewage Back Up Into Your Tub
One of the most annoying problems homeowners face has to do with the sewage system or plumbing. For instance, there’s the issue of sewage backing up into the tub. It’s gross, a health risk, and a possible sign of something more serious.
When this happens, we strongly suggest that you take care of it immediately. If not, it could lead to disease, and sometimes, even death. So, what should you do? Why is sewage in your bathtub? And how do you get rid of sewer backup in your bathtub? Let’s find out!

What Is the Sewer Line?
The shower drains, bathroom sinks, drains, and toilets, are all connected. They connect to larger drains that run around the house. These larger drains carry water and sewage to what is known as the “sewer line.”
This sewer line is a sort of pipe running from the house and goes under the yard. It is connected to the sewer system of the city. As the name suggests, it carries sewage out of the house. The sewage it transports includes old wash water and toilet waste.
If the sewer line is blocked or clogged, the water and sewage can’t move away from your house properly. When that happens, the sewage is more than likely to back up into your property, going through the bathtub and other drains.
What Causes Sewer Backup in the Bathtub?
The most common cause of sewage coming up through the shower drain or bathtub is a clogged sewer line. Wastewater goes back into the house when the single drain pipe that leads it out of the property is blocked. The question is what can clog or block a sewer line? Well, anything really, but the usual culprits are:
- Oil and grease
- Hair
- Food waste
- Dirt
- Rocks
- Tree roots
- Hard water buildup
- Baby wipes
- Other non-flushable items
Tree roots are especially notorious for getting into sewer lines due to being a source of nutrients for them. But by growing inside the sewer lines, the roots eventually lead to obstructions that increase water pressure and send wastewater back to the house.
Our resident home repair guru, John Turpin, has provided a list of common reasons why your bathtub may have sewage backing up and what to do to prevent or fix it.
What to Do When Sewage Is Backing Up Into the Tub?
It is usually best to call a plumber as soon as you see that wastewater or even poop is coming up through the bathtub. But depending on the severity of the issue, there are some tricks you can try at home. How do you get rid of sewer backup in the bathtub? Follow the steps below.
1. Turn Off the Water
Turn off the main water supply when you recognize signs of a blocked sewer line. This way, you can avoid extra water from flowing into other areas of the house, especially if they are already backed up.
2. Inspect the Vent Pipe
Once you’ve turned off the main water valve, you should check the vent pipe and confirm if it is indeed blocked. Go up to the roof to inspect the vent pipe typically located over the bathroom. If there’s any blockage, pull them out using a retrieval tool.
3. Try a Plunger
After removing any blockage you find in the vent pipe, you can turn your attention to clearing the clogs near the drain surface. You can do this using a plunger, which should dislodge the usual clogs. It won’t work, though, if the blockage is deeper.
4. Use a Drain Snake
Besides the plumber, one useful method you can try for clearing clogs down the sewer line is the drain snake. It’s also easy enough to use – feed the snake down the drain or toilet and spin clockwise as it snakes its way down.
Continue your way down until you feel a block and then slowly twist counterclockwise to pull the drain snake out. If this method worked, you should see whatever clogged the drain pulled out by the snake.
5. Call in the Professionals
Did the steps above work? If yes, that’s good. But if it didn’t and sewage is still backing up into the tub, you need expert help. This time, we suggest calling a plumber because the source of the problem might be bigger than just clogs.

Other Tips to Get Rid of Sewer Backup and Clogs
Below are some more tips that can help you fix sewage backup and clogs.
Use a Hair Catcher
Putting a hair catcher in the tub should help minimize the hair that gets into the drain. But to make the most of it, be sure to clean it regularly. It also helps if you brush your hair before showering, so you can remove loose hair that can clog the drain before bathing.
Install a Water Softener
Hard water buildup is one of the possible reasons behind sewage backup. You can fix this by installing a water softener. The water softener reduces the buildup of calcium and magnesium, thus lessening water pressure and blockage.
Hose Off Mud and Sand Outside
Dirt and debris, as mentioned, is also a common cause of sewage line blockage. Hosing off mud and sand outdoors before you enter the shower can prevent them from causing bathtub and toilet clogs.
Install Bathtub Drain Stopper
You can avoid items getting dropped down the drain of the tub by using a bathtub drain stopper. Install one so that things that shouldn’t be in the drain like little toys, rocks, etc. don’t become a blockage that causes wastewater to back up.
DIY Mixtures
You can de-clog the drain using mixtures of ingredients you can usually find in your kitchen. Here are some mixtures you can try:
- 1/2 cup of vinegar, 1/4 cup of Borax, and 1/4 cup of salt
- Mix them in a pot of boiling water and then pour them down the drain with hot water. Allow it to sit for an hour or so before rinsing it with tap water.
- 1/2 cup of vinegar and 1/2 cup of baking soda
- Pour the cup of baking soda first and then the cup of vinegar. Plug the drain and allow the two ingredients to sit for about an hour. Later, unplug the drain and clear it by pouring hot water until the clog is gone.
- 1/2 cup of salt and 1/2 cup of baking soda
- Mix the two ingredients and then pour into the drain. Allow it to sit for 30 minutes or an hour, even overnight. After some time, pour boiling water down the drain to clear it.
Is the Sewage Water Backing Up the Bathtub Dangerous?
The sewage backing up into your tub is not only gross but also dangerous to your health. It’s a health risk because it contains harmful microorganisms and bacteria that can harm you. When this happens, you’ll need to address the root cause of the problem before doing some deep cleaning.
What Are the Warning Signs of a Blocked Sewer Line?
Knowing when your sewer line is blocked can help you minimize pipe damage and prevent sewage backup. Some of the signs that help you recognize it include slow-draining water, frequent clogs, and migrating wastewater. Hearing gurgling sounds while draining also indicates that your sewer line might be blocked.
Should You Hire a Professional to Fix Sewage Backup?
Some plumbing problems are simple enough that you can fix them on your own. You can also try to address a sewage backup in your home. However, it’s often only a temporary stop and the problem comes back more serious after a while. This is why it’s best to let a professional deal with a clogged sewer line. Professionals can prevent sewage from backing up into your tub without creating costly or permanent damage.
Hire a Local Plumbing Pro
The methods above are effective DIY tips about what to do if you have sewage backing up into your bathtub. But if you need professional help, then don’t hesitate to contact a local plumbing pro using the phone number or form on this page.