Does homeowners insurance cover sewer backup in Michigan?

Key facts

• Sewer backup coverage depends on your policy wording and any water backup endorsement.
• A homeowners policy does not cover flood. Flood coverage is a separate policy.
• For a public sewer backup, Michigan law gives you 45 days after you discover the damage to send written notice to the agency.
• A backup that comes from a sump system, building drain, gutter or downspout on your own property falls outside that law.
• In Detroit, call DWSD at (313) 267-8000 first to get a Service Request number.
• Photograph the water line, the drain and every damaged item before cleanup.

Where the water came from, and where to look

What does a homeowners policy say about sewer backup?

Sewer and drain backup is often written into a policy as its own endorsement or rider. Whether you have it depends on what was added when the policy was written or renewed.

Backup coverage can carry its own limit, separate from the limit on your house. The endorsement page shows the amount.

The wording in each policy is different. Your own policy wording decides what you have. Do not guess from what a neighbor's policy paid.

1. Find your declarations page. Look for words such as water backup, sewer backup, sump overflow or drain backup.
2. Write down the backup limit and the deductible if the page lists them.
3. Before you make any calls, have the damage documented and measured. A local restoration pro does this free.
4. Keep the photos, moisture readings and written scope together in one folder.

Is a sewer backup the same as a flood?

Insurers sort water losses by where the water came from. Water that comes up through a floor drain or toilet is a backup. Water that comes over the ground from outside is usually a flood. Water that rises in a sump pit because the pump failed is a sump overflow.

A homeowners policy does not cover flood damage. Flood coverage comes from a separate flood policy, and it covers qualifying flood events.

When you report a loss, describe what you saw. Say where the water came in and when. Do not call it a flood if the water came up through a drain.

What if the city sewer caused the backup?

Michigan has a separate path for backups that come from a public sewer. You send a written notice of claim to the agency that owns or runs the sewer. You must send it within 45 days after you discover the damage.

The notice is short. It lists your name, address and phone number, the address of the damaged property, the date you found the damage and a brief description of the claim.

The law does not treat every backup as the public sewer's fault. A blockage in your own service lead does not count, unless the agency caused it. A connection on your property, such as a sump system, building drain, gutter or downspout, can also take the event outside the law.

The agency can ask to inspect the damage. The law says you must not unreasonably refuse. Keep damaged items and take photos before you throw anything away.

1. Call the city or sewer authority as soon as you see the backup. Write down the date, time and the name of the person you spoke with.
2. Ask who must receive the written notice of claim, and get that name and address.
3. Send the written notice within 45 days of the day you found the damage. Keep a copy and proof of the date you sent it.
4. Take photos and video of the water line, the drain and the damaged items before cleanup.
5. Get a free damage review so the water line, moisture readings and losses are on record. A city claim and an insurance claim can run side by side.

What should Detroit residents do after a sewer backup?

The Detroit Water and Sewerage Department asks you to call (313) 267-8000 before you file. You get a Service Request number on that call. You need that number for the Notice of Claim form.

The city page also gives a 45-day window from the day you discover the backup. Other Michigan cities have their own process, so call your city to ask.

How do I stop the next sewer backup?

A backwater valve lets sewage flow out of the house and blocks it from coming back in. It usually sits in the sewer lateral outside the house, or in the basement floor. The valve is part of your lateral, so you own it and you maintain it. Plumbing work like this needs a permit.

A sump pump with a battery backup keeps working when the power goes out. Floor drains clog with lint and debris, so check them before storms. Do not flush wipes or pour grease down drains, because they can block your sewer line.

1. Ask a licensed plumber to camera the sewer line if drains run slow or back up during laundry or showers.
2. Ask the plumber if a backwater valve fits your home, and which type.
3. Ask if the job needs a permit, and who pulls it.
4. Test your sump pump by pouring water into the pit.

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