Sewer Backups & Backwater Valves in SF

A sewer backup happens when wastewater can't flow out to the city main and instead comes back up through your lowest drains — often during heavy rain or when a lateral is blocked by roots or grease. A backwater valve is a one-way gate installed in your sewer line that lets waste flow out but closes if the city sewer surcharges, protecting the home. They're especially worth considering for low-lying lots and homes with a history of backups. A camera inspection confirms the lateral's condition first.

• Backups often hit during heavy rain or when a lateral is blocked by roots or grease.
• A backwater valve is a one-way gate that blocks city-sewer surcharge from entering the home.
• Low-lying lots and homes with past backups benefit most.
• Start with a camera inspection to see the lateral's real condition.