Preventing a Costly Sewage Backup in Your Home

Updated: May 22, 2024

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If wastewater has made its way back into your home, the likely culprit is a clogged or damaged sewer line. Sewer backups can be caused by various factors, including septic system deterioration due to age, combined pipelines, tree root intrusion, blockages or faulty storm/ground water connections.

This unfortunate experience can be costly. It can also cause significant damage to your home’s structure, electrical systems and furniture. Additionally, sewer backups can be a health and environmental hazard.

Knowing the warning signs, maintaining your septic system every three to five years and ensuring you have the right homeowners insurance coverage can help protect your home and finances.

US Septic System Facts


Sewer backups can lead to huge expenses and serious health risks. Knowing the costs, possible effects and common causes can help you prepare and protect your home.

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There are over 800,000 miles of public sewers in the country. Around 500,000 miles of private sewers connect homes and businesses to these public lines.

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Replacement of a septic system can be expensive, ranging from $5,000—15,000 for a conventional system.

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A septic system more than 25—30 years old is considered close to the end of its lifespan.

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Sewage backups often occur due to system deterioration, combined or damaged pipelines, tree roots and pipe blockage.

Factors Causing Sewage Backup

Various factors may cause sewage backup. Although some may be beyond a homeowner's control, such as flooding, vandalism and blockages in the city’s main sanitary pipelines, most can be prevented. Conducting regular inspections, proper maintenance and taking precautions can help reduce the likelihood of an issue.

System age

Sewer systems tend to support multiple homes and establishments. An increase in connections over time can contribute to the deterioration of sewer systems, especially old ones. This can cause more sewage backups and overflows.

Damaged pipes

Even a small crack can harm your pipes. Whether it’s due to external factors or outdated plumbing, it’s important to check your home’s plumbing for possible damages regularly.

Combined pipelines

Some sewer systems combine raw sewage and stormwater. This increases the risk of sewage backup, especially during rainstorms when the lines are exposed to more volume.

Tree roots

Surrounding trees and shrubs’ root systems may make their way into sewer lines and pipes. These invasions may cause damage to sewer lines or cause clogging as the roots grow larger.

Clogged pipes

Sewage backups in homes are most commonly caused by clogged pipes. Pouring grease down the drain and flushing non-flushable items lead to blockages.

An illustrative image of a homeowner learning about a homeowner learning warning signs of a sewer line backup.

5 Warning Signs of a Sewer Line Backup

Your best protection against sewage backups is prevention. However, if the unexpected happens, knowing the signs can help reduce the extent of the damage. Homeowners must be observant of their drains and toilets. Subtle signs like slow drains, gurgling noises and foul odors indicate sewer issues.

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    Slow drains

    You may notice slow-moving drains. It may also take longer than usual to flush your toilet.

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    Gurgling noises

    Run water to check your sinks and drains for bubbles, which indicate trapped air due to the water passing through clogged pipes. Bubbles may also appear in your toilets after flushing.

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    Foul odors

    Drains are supposed to transport wastewater away from your house. If you smell sewage stench, there might be something clogging your drains and causing a backup.

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    Clogged drains or toilets

    A clogged drain or toilet from time to time is normal. Suppose there are multiple clogs in your home at the same time. There’s likely a sewage backup in your system.

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    Backup in another drain

    If you drain water and it causes a backup in another drain, you’re likely experiencing a sewage backup. For instance, if water comes up through your shower drain every time you run water in the bathroom sink, it may be time to contact a plumber.

An illustrative image of sewer backups and how to prevent them.

Prevent Sewage Backups in Your House

Homeowners share the responsibility for sewer maintenance with the city. Homeowners are responsible for the sewer lines from their homes to the street. These include sections outside their property lines. On the other hand, the city takes care of the main public sewer line or the line to where all private lines connect.

If you experience a sewage backup and the issue occurs in the line you’re responsible for, you’ll have to pay for the repairs. So, it’s crucial for you to prevent future backups by taking extra precautions.

Get a sewer line inspection

A thorough inspection will help locate issues early. You can find out if any pipes require repairs or replacement. If there are trees nearby, conduct a root inspection. If necessary, contact a professional to trim back noticeable tree roots.

Clean your sewer lines

One of the best ways to prevent sewage backups is to ensure that your sewer lines are clean. An annual sewer cleaning can reduce the risk of plumbing issues.

Dispose of grease and paper products properly

Never flush paper products, such as feminine products, wipes and paper towels, as they can cause clogging. The following organic products should never go down drains:

  • Grease, fats and oils
  • Coffee grounds
  • Food waste (unless you have a garbage disposal)
  • Starches
Replace old sewer lines

Aging sewer lines are typically prone to damage. Consider changing old plumbing systems. Consult a professional to determine the best types of pipes for your home.

Consider a backflow valve

Installing a backflow valve provides additional protection against sewage backups. If properly installed, it can prevent sewage from coming back into your home. Make sure you hire a qualified plumber to avoid issues.

An illustrative image of a homeowner learning about the costs of sewage backup restoration.

How Homeowners Insurance Can Help

Having the right homeowners insurance coverage can help you pay for water damage due to sewage backup. For instance, a standard policy typically covers sewer line replacement under dwelling coverage. However, there may be limitations in the coverage amount and covered external events. That said, exact coverage may vary per insurance provider.

Before purchasing a policy, clarify the coverage details with your insurance agent. Ask about coverage limits and covered events. If you’re after both affordability and quality, compare home insurance quotes from multiple companies to find your best offer.

What to Do During a Sewage Backup Emergency

Realizing that there’s a sewage backup in your home can be overwhelming, but taking the proper steps can help mitigate the damage before the restoration team arrives. The following are some helpful tips you can use in the event of a sewer line emergency. Also, ensure your family’s safety before taking any of these steps.

Assess the situation

The first thing you need to do is determine the extent of the damage. Check walls, floors and your belongings for water damage. Avoid contacting sewage as it can be dangerous to your health.

Turn off the electrical circuit in the affected area

Once you determine which areas are affected, shut off their electrical circuits to prevent electrocution. If dirty water comes out of your drains, turn off your main water valve immediately to prevent further overflow.

Find the cause (if possible)

Locate the blockage if you can. Check your sinks, drains and toilets for signs of clogging. If you can’t clear the blockage, hire a plumber.

Start the cleanup

Depending on the situation, you may need to leave the cleanup to professionals. If you decide to clean the affected area yourself, it’s essential to wear protective clothing and use a face mask and rubber gloves.

You should also check for damaged wallboards and debris. Remove spillage and wet vacuum the overflow area. Mop the floors and wipe your walls with disinfectant.

Additional Resources

Learning more about sewage backups and understanding the risks can help you better handle sewer issues. The following resources can provide helpful information.

About Nathan Paulus

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Nathan Paulus is the Head of Content Marketing at MoneyGeek, with nearly 10 years of experience researching and creating content related to personal finance and financial literacy.

Paulus has a bachelor's degree in English from the University of St. Thomas, Houston. He enjoys helping people from all walks of life build stronger financial foundations.