Sewage backup cleanup: what causes it, the health risks and the first steps to take

First steps after a sewage backup: protect people, then make calls

Before any cleanup, deal with the risks to people. King County's guidance puts safety first, then getting help from your sewer agency, your insurer and, if needed, a restoration crew.

• If the area can't be closed off, children under 2, adults over 60 and anyone with respiratory problems, allergies or a weak immune system should leave the home.
• Stay out of standing sewage. Wading in risks electric shock, contamination and injury from moving water.
• Switch off breakers and unplug appliances in the affected area, but never while standing in or touching the water.
• Call your local sewer agency and your insurance company straight away.
• Photograph everything before you move it.

What causes sewage backup: usually a blocked side sewer

Your insurer and local sewer agency can help you work out the right course of action.

Health risks of sewage in a basement

King County notes it contains disease-causing contaminants, and flooded areas add the danger of electric shock and injury.

• Contamination: sewage carries disease-causing organisms, so cleanup must be careful and thorough.
• Higher-risk people: young children, older adults and those with breathing problems or weak immunity should leave if the area can't be isolated.
• Electrical: water and live circuits together can cause shock, so cut power safely first.

Insurance after a sewage backup: check coverage and document first

King County advises knowing ahead of time what your home insurance covers for sewer backups. You do not have to wait for the adjuster: you have the right to start emergency mitigation before an adjuster calls you back. We will tell you what to expect before you file anything.

We write the scope in Xactimate, the pricing software insurers use, so it holds up with adjusters, and in most losses we bill your carrier directly instead of you. For insurance, an estimate is only required for putting the house back together.

Mop it up yourself or hire a crew: what tips the decision

King County suggests a professional restoration service when there is more water than mops and sponges can absorb.

• Small amount, area can be isolated: follow Public Health — Seattle & King County's indoor sewage cleanup steps.
• More than mops can handle: King County points to professional water damage restoration.
• Hidden moisture: we bring infrared cameras and moisture detection equipment to find it behind surfaces before it becomes mold.
• If a wet wall bay gets closed up anyway, you end up paying for the same repair again next spring.
• Our technicians are IICRC certified.

How a sewage cleanup estimate works: we see it first

We can't give a number before we've seen the property, and we won't guess at a figure sight unseen. We come out, look at your home, and then sit down with you to go through an estimate.

Written bids let you compare scope and price side by side, and reference checks show reliability and communication. Before you sign, look the contractor up on Washington L&I's free Verify tool.

Common questions