Few things are worse than walking downstairs to find sewage coming up through the basement floor drain. After the cleanup, the next question is almost always the same: will my insurance pay for this? In Missouri, the answer depends on one line in your policy that many homeowners never notice until they need it.
The Short Answer
A standard Missouri homeowners policy usually does not cover sewer backup. Most policies exclude water that backs up through sewers, drains or sump pumps. To be covered, you typically need a separate water backup (sewer and drain) endorsement added to your policy. Flood insurance generally does not cover ordinary backups either, unless the backup is directly caused by a general flood.
Which Policy Covers Which Water?
| What happened | Typically covered by |
|---|---|
| Burst pipe, failed water heater, appliance leak | Standard homeowners policy (sudden and accidental) |
| Sewage or water backs up through a floor drain | Water backup / sewer and drain endorsement |
| Sump pump fails or overflows | Water backup / sump overflow endorsement |
| Rising water from a river, creek or storm runoff | Flood insurance (NFIP or private) |
| MSD public sewer overcharged or blocked | Possible MSD reimbursement, plus your endorsement |
| Slow leak or long-term seepage | Often excluded as wear and tear |
Every policy is different. Always check your own declarations page and policy language.
What a Water Backup Endorsement Covers
A water backup endorsement typically pays for damage caused when water or sewage backs up through a sewer line, floor drain or sump pump. That can include sewage cleanup, removal of contaminated flooring and drywall, disinfection, drying and repairs, and sometimes damaged belongings, up to the endorsement limit.
Limits are commonly offered in amounts like $5,000, $10,000 or $25,000. That sounds like a lot until you price out a finished basement: carpet, pad, drywall, trim, furniture and stored items can exceed a $5,000 limit quickly. If your basement is finished, consider a higher limit.
What it usually does not cover
- Repairing or replacing your sewer lateral itself.
- Damage from floodwater entering from outside.
- Damage from long-term seepage or poor maintenance.
Why Sewer Backups Are So Common in St. Louis
Much of the City of St. Louis and older parts of St. Louis County are served by combined sewers that carry both storm water and wastewater in the same pipes. During intense storms, those pipes can fill up and push water back into basements through the lowest opening, usually the floor drain. The region saw this on a massive scale during the record flash flooding of July 26, 2022.
Backups also happen in dry weather when tree roots, grease or collapsed clay pipe block a home’s private sewer lateral. In older neighborhoods like South St. Louis City, Affton and Kirkwood, original clay laterals are often 70 years old or more.
If the Public Sewer Caused It, MSD May Help
If you live in the Metropolitan St. Louis Sewer District service area and an overcharged or blocked MSD public sewer caused your backup, MSD may reimburse part of the cleanup. According to MSD, it reimburses up to $3,000 with a $100 deductible for backups from an overcharged sewer, and covers adjusted losses when a public main is blocked. You must contact MSD within 30 days. Read our full guide: MSD sewer backup reimbursement in St. Louis.
What To Do Right After a Sewer Backup
- Keep children and pets away and avoid contact with the water.
- Stop using sinks, toilets, showers and appliances that drain into the sewer.
- Photograph and video everything before cleanup starts.
- Call your insurance company and, if you are in MSD territory, call MSD at (314) 768-6260.
- Call a professional sewage cleanup company. Sewage is Category 3 black water and should not be cleaned up with household fans and bleach.
Midwest Flood Restoration documents the loss, cleans and disinfects to IICRC standards, and bills your insurance directly. See typical pricing in our St. Louis water damage cost guide.
How To Protect Yourself Before the Next Storm
- Call your agent and ask whether you have water backup coverage and what the limit is.
- Raise the limit if your basement is finished or used for storage.
- Ask a plumber about a backwater valve and a camera inspection of your lateral.
- Keep grease, wipes and paper towels out of drains.
- Store valuables in plastic bins off the basement floor.
For more prevention tips, see how to prevent basement flooding in St. Louis.
Frequently Asked Questions
Does homeowners insurance cover sewer backup in Missouri?
Not usually by default. Most standard Missouri homeowners policies exclude water that backs up through sewers or drains. Coverage is typically added with a water backup or sewer and drain endorsement for an extra premium, often with limits of $5,000 to $25,000. Check your declarations page or ask your agent to confirm.
How much does a sewer backup endorsement cost?
A water backup endorsement is usually one of the less expensive add-ons to a homeowners policy, often in the range of tens of dollars to a little over one hundred dollars per year depending on the insurer and the limit you choose. Compared with the cost of cleaning up a sewage-filled basement, it is usually worth considering.
Does flood insurance cover sewer backup?
Only in limited cases. A National Flood Insurance Program policy may cover sewer backup when it is directly caused by a general flood in the area. Backups caused by overloaded sewers during ordinary heavy rain, or by a clogged lateral, are generally not covered by flood insurance and require a backup endorsement on your homeowners policy.
Who pays if the city sewer caused my backup in St. Louis?
If you are in the Metropolitan St. Louis Sewer District service area and an overcharged or blocked MSD public sewer caused the backup, MSD may reimburse cleanup costs, up to $3,000 with a $100 deductible for an overcharged line. You must contact MSD within 30 days. Backups from your private lateral are the owner’s responsibility.
Sewage in Your Basement? We Are Available 24/7
Midwest Flood Restoration provides IICRC-certified sewage cleanup across St. Louis, St. Charles, Jefferson County and the Metro East, and we bill your insurance directly. Call (314) 772-1788.
CALL NOW! (314) 772-1788