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What to Do if a Backup or Flooding Occurs

When to Contact a Plumber 
Typical SF Property with Sewer Lateral InfoIf you experience a backup from your plumbing or flooding, contact a plumber. A plumber can confirm where the issue is your house plumbing or sewer lateral. Depending if the issue is located in the upper (between the property and curb) or lower part (between the curb and sewer main under the roadway) of the sewer line will determine if the city of San Francisco or the property owner is responsible to fix the issue. Learn what property owners need to do for their sewer laterals at

Report Flooding
Please report flooding due to a rainstorm to the City’s Customer Service Center at, via the mobile app, or by phone at 3-1-1. Select “Flooding & Sewer” request so your report will be forwarded to the appropriate City agency.


Health and Safety Tips

  • Floodwater can contain contaminants washed off the street, including bacteria and parasites. Avoid coming into direct contact with floodwater and keep children and pets away. 
  • If you must encounter floodwater, follow these precautions: 
    • Wear waterproof boots, gloves, eye protection and clothes that are either water resistant or disposable. 
    • Keep exposure with floodwater to a minimum, avoid splashing, and keep the water out of your mouth, eyes and nose.
    • Bathe or shower thoroughly with soap and water, wash all contaminated clothing in hot water and a detergent after you come in contact with floodwater.
    • Make sure tetanus immunizations are up to date. If you are on chemotherapy or any health issue that weakens the immune system, consult with your primary health care provider.
    • If you become ill with fever, nausea, vomiting or diarrhea after exposure to possibly contaminated floodwaters, contact your health care provider.
    • Electrical hazards: When entering flooded areas, be aware of electrical hazards. Don’t touch any electrical equipment unless you are absolutely sure it is properly grounded or that the power is off. Also, don’t operate any electrical equipment that is not specifically designed for use in wet locations.
    • Never handle a downed power line. If clearing or other work must be performed near a downed power line, contact the utility company.
      o PG&E suggests that you shut off your gas and electricity during major flooding, if you know how to do so safely. Visit PG&E’s emergency preparedness page or call them at (800) 743-5000. Do not attempt to do so if you must stand in or make contact with water.
    • Carbon Monoxide: Operate all gasoline-powered devices outside. These devices release carbon monoxide, a deadly, colorless and odorless gas.
    • Never assume that water-damaged structures or ground are stable.
    • Cover or close vents, such as heater vents, to prevent spreading of contaminants and odors.


  • Remove any excess water from the property by using pumps or by mopping.
  • If you have a large amount of water in your basement and no drain present, you may need to buy or rent a sump pump to get rid of the water.
  • Consider using an insured professional cleaning service.
  • Wear gloves while cleaning and wash hands thoroughly after handling any soiled items.
  • Clean hard surfaces such as floors and fixtures with hot water and a mild detergent. Rinse it with a bleach solution: ¼ cup of liquid household bleach to one gallon of water.
  • CAUTION: Do not mix bleach with other cleaning products that contain ammonia.
  • Saturated fabrics including carpeting, usually cannot be adequately cleaned.
  • Disinfect mops, brooms, and brushes used for clean-up with a bleach solution.
  • Yards that have been contaminated by floodwater should be disinfected by a liberal application of lime. Children and animals should be kept away from limed areas until the lime is no longer visible. 


  • Extreme storms and flood events increase exposure to indoor dampness and mold. The most important thing you can do to prevent mold growth is to identify and remove the source of water and then dry out your home within 48 hours; use dehumidifiers and active ventilation.
  • Remove and dispose of mold-contaminated materials.
  • Avoid breathing dust (fungal spores) generated by wet materials. Consider using an N-95 NIOSH-approved disposable respirator.
  • After working with mold-contaminated materials, wash thoroughly, including the hair, scalp, and nails.
  • For more info :

Food Safety

  • Discard any food, drinking water or medicines that may have come into contact with floodwater.
  • Undamaged, commercially canned foods can be saved if you remove the can labels, thoroughly wash the cans, and then disinfect them with a solution consisting of one cup of bleach in 5 gallons of water. Relabel your cans, including expiration date, with a marker.
  • Food containers with screw-caps, snap-lids, crimped caps (soda pop bottles), twist caps, flip tops, and home canned foods should be discarded if they have come into contact with flood water because they cannot be disinfected.
  • For infants, use only pre-prepared canned baby formula that requires no added water.

Keep Records of Damage and Cleanup

  • Take pictures and videos! Be sure to document damages when possible.
  • For National Flood Insurance, contact your local insurance agent or go to: or call 1-800-427-4661 - keep records and receipts of damage and clean-up.
  • If you think the city caused damage to your property, you may contact the City’s Attorney’s Office Claims Division at 415-554-3900 and/or file a claim with the San Francisco Controller’s Office at Records such as 311 calls, photos, receipts should also be provided. 
Small Business Disaster Relief Fund
A fund aimed to assist small businesses after a disaster such as flooding and fire, with up to $10K for inventory replacement, equipment purchases, security deposits for new leases, employee salaries, or other expenses and to stabilize cash flow. For more information:

Floodwater Grant Program
Consider applying for reimbursement up to $100k for eligible property owners for implementing projects on their properties to protect during heavy rains and minimize impacts. Visit

For ALL resources on how to get rain ready, visit
Last updated: 4/1/2020 5:08:16 PM