How to help prevent sewer backups at your home
By Allstate
Last updated: January 2026
Have you ever experienced standing water in your home after a heavy rainstorm? If water has come up through plumbing fixtures or if you have standing water over a drain in the floor or bathroom, you may be experiencing a sewer backup. Learn the common causes of sewer backups and what you can do to help prevent one in your home.
What causes a sewer backup?
According to the Insurance Information Institute (III), common causes of sewer backups into a home may include:
- Sewage pipe blockages caused by tree roots
- Aging home and city sewer systems that need repair
- Blocked city sewage mains
- City pipelines accepting rain and sewage water that have been overwhelmed with water after heavy rainfall
When one of these problems exists, sewer water can get forced up through your home's sewer pipes. Large quantities of sewage-contaminated water may come up through toilets, floor drains and shower or bathtub drains, says the III.
What are signs of a potential sewer backup?
If you notice any of these issues at your home, you may be at risk for a sewer backup and should call a professional for help:
- Floor, shower or bathtub drains making gurgling sounds or backing up with water, according to Angie's List.
- Water rising from your home's sewer cleanout pipe, says the Montgomery Township Municipal Sewer Authority.
How can you prevent a sewer backup?
You may be able to help protect your home from a sewer backup by taking the following preventive measures, according to the III:
- Install a backup water valve: A licensed plumber can install a water valve in sewer or drain lines. This valve lets sewage water flow out of the pipes, but not back in.
- Properly dispose of household waste: Items like paper towels do not decompose quickly and can contribute to clogged sewer lines if they are flushed down a toilet. And in the kitchen, be sure to properly dispose of cooking grease — if you pour it down the sink, it can solidify in the pipes.
- Inspect and trim tree roots: If you have noticeable tree roots throughout your yard, you may need to have a professional trim them back to help lessen the risk of them growing into a sewer line.