Sewage Backups

Sewage backups are often caused by an overwhelmed sewer system during heavy rains or a blockage in the system. This can include cracks due to tree roots or blockages from grease, hair, and other solid material buildups in the pipes. Sewage contains bacteria, viruses, and germs that can be harmful to your health and can contaminate the area in which the backup occurred. Accidental ingestion or contact with raw sewage can cause gastrointestinal illness, skin infections, or rashes. It is important to stay away from the contaminated area until professionals can come to assess the damage.

Preventing Sewage Backups

Do not flush or dump solid materials or oil down the drain, as this can cause blockage. Use a drain catch and throw food scraps in the trash. If you have a grease trap for a drain, clean it regularly. Also, make sure to keep storm drains clean and free of debris. 

How to React to a Sewage Backup

If you see sewage pooling in your home, immediately call our 24/7 Emergency Dispatch at 412-255-2423 (Press 1). Please note the following to share with the dispatcher:

  1. Where the sewage backup is within the home
  2. If this is a recurring issue
  3. If the backup occurs when water is used inside of the building
  4. If the backup only occurs during a rain event


We will dispatch a crew to assess the situation, which includes determining if the problem is with the sewer main or with the sewer lateral.

  • If it is a broken or clogged sewer main, we are responsible.
  • If it is a broken or clogged sewer lateral, the property owner is responsible.

While waiting for a crew to arrive, contact neighbors to see if they are experiencing problems.

You may begin the cleanup process once the problem is corrected and the sewage has drained from your property.

Cleanup Steps

The following are critical tips regarding how to clean up a sewage backup:

  • Wear protective gloves, boots, masks, and eyewear before beginning the clean-up. You may also call a professional remediation company that is equipped to handle this task.
  • Clean and disinfect washable surfaces that have come in contact with the sewage.
  • Wash with soap and water, and then disinfect with a mixture of a quarter cup of household bleach per gallon of water.
  • Discard upholstered furniture, mattresses, bedding and stuffed toys soaked in floodwaters.
  • Sweep or mop up soaked and soiled carpeting, then shampoo with a commercial rug cleaner.
  • Clean, dry, and check your furnace, water heater, washer, dryer, and other appliances before using.
  • Don't handle electrical equipment in wet areas. Call a plumber or an electrician for professional service.
  • To remove odors from refrigerators and freezers, use warm water with a detergent and wipe dry.
  • If an odor persists, try a solution of one teaspoon of baking soda or one cup of household ammonia per gallon of water.
  • Throw away all foods that have contacted floodwaters.
  • Make sure everyone involved in the flood cleanup has an up-to-date tetanus shot.

Property Damage

Most sewer system backups are unforeseen events, and, generally, the Pittsburgh Water and Sewer Authority is not liable for damages. If the customer believes the backup was the fault of PWSA, they can contact and file a claim.

Homeowner's insurance does not always cover the cleanup and repairs after a sewage backup event; this service may have to be purchased separately. Contact your insurance provider to ensure you are covered.

What We Are Doing to Prevent Sewage Backups

PWSA does everything possible to prevent backups from happening in the system’s main lines. We are moving towards separated sewer systems, those having one pipe for sanitary sewer waste and one for stormwater, to help to minimize stress on the sewer system. Also, as you may learn on our Stormwater Plans page, we are taking a more deliberate approach about the way stormwater is managed across Pittsburgh. Lastly, we monitor, clean, and replace storm drains to allow for proper drainage during a rain event.