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The City of Portland, Oregon

Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

1120 SW 5th Ave, Suite 613, Portland, OR 97204

More Contact Info

Sewer Backups

What To Do If You Experience a Sewer Backup

Sewer pipes can sometimes become plugged with debris or grease, which can cause sewers to back up into homes through basement drain pipes, sinks, toilets or shower drains. Portland's combined sewers can also back up during very heavy rain storms when stormwater runoff fills the pipes to capacity.

Environmental Services works to build and maintain a safe, efficient sewer system, and identify and replace sewer lines with capacity problems or that are in danger of failing.

Reporting Sewer Problems

The sewer line from your home to the city sewer line in the street can also become plugged with debris or grease and cause backups in your home. It’s best to call a plumber first to investigate the cause of the backup. If the plumber finds a problem in the line from your home to the street, the repair is the property owner's responsibility. If the plumber determines the problem is in the city sewer line, call the City of Portland Maintenance Hotline at 503-823-1700. For information about filing a claim for damages caused by a backup of the city’s sewer system, call the Bureau of Risk Management at 503-823-5101.

What To Do After A Sewer Backup

For professional help to clean up after a backup, look in the telephone directory under carpet cleaning. If you begin the cleanup yourself, remember that bacteria in sewage is a health hazard and take some basic precautions.

  • Wear gloves, boots, rain gear and other protective clothing.
  • Avoid coming into contact with sewage or material contaminated by sewage. Be especially careful to not let sewage come into contact with your face or eyes.
  • Protect cuts and scrapes. Immediately wash any wound that comes into contact with sewage.

Cleaning Up

  • Wash all surfaces with hot, soapy water.
  • Disinfect all surfaces with a solution of one part household bleach to ten parts water.
  • Wash hands thoroughly after cleaning up.
  • Wash and disinfect clothing and supplies used in cleaning up.

Keep Sewers Fat Free

Grease blocking sewer pipes is a serious maintenance problem for both the city and private property owners. Grease washed down the sink sticks to the insides of sewer pipes. The build-up restricts flow and can block pipes completely, causing raw sewage to back up into your home or overflow into streets and streams.

Home garbage disposals don't keep grease out of sewer pipes and products that claim to dissolve grease may dislodge a blockage, but will only cause problems further on down the line.

Here are some guidelines for keeping sewers fat free.

  • Never pour grease down sinks or toilets.
  • Pour grease and oil into a can, store it in the freezer and put it in the trash when it's full.
  • Scrape food scraps into a can or the trash.
  • Catch food scraps with baskets or strainers in sink drains and throw scraps in the garbage.
  • Get more information about keeping grease out of sewers.

For Restaurant and Building Owners

  • Recycle grease and oil.
  • Don't pour grease or oil into sinks, floor drains, or on a parking lot or street.
  • Use a grease trap or interceptor that is designed, installed and maintained correctly.
  • Never put solids into grease traps or interceptors.
  • Check and maintain grease traps and interceptors regularly.
  • Get more information at Cut Through the FOG

Sewer Backflow Prevention Program

A sewer backflow prevention device may prevent sewage from backing up into your basement. It’s a one-way valve installed in your home’s drain line that allows wastewater to flow out, but swings shut to help prevent sewage from flowing back in.

The City of Portland created the Sewer Backup Prevention Program to help pay for installing sewer backflow prevention devices. The program works this way:

  • Residents of combined sewer areas subject to basement flooding may apply. Environmental Services staff can tell you if your home is in such an area.
  • Participation is one time per address.
  • Once an application is approved, the resident hires a plumbing contractor.
  • The resident pays the first $100 of installation costs. The City of Portland will pay the next $1,500.
  • The reimbursement is taxable income.
  • The resident is responsible for any remaining costs. Installation typically costs around $1,600.
  • The device belongs to the resident. The resident is responsible for maintenance and repair.

The property owner is responsible for any future sewer backups at the address after participation in the program.

Call Environmental Services at 503-823-5366 for an application.

Basement Moisture Problems

If you have continuing problems with seepage or moisture in your basement, please let us know by taking our online survey.