Backwater Valves
Backwater valves are protective devices installed in a plumbing drainage system to prevent the reverse flow of wastewater (sewage) from entering a building. Backwater valves are are typically installed in a horizontal drain line with access for inspection and maintenance. Most backwater valves are designed with an internal flapper, which allows normal flow out, but prevents reverse flow back in. This helps protect interior spaces from flooding, contamination, and property damage - especially in buildings with fixtures located below street level, such as basements, where the risk of sewage backup is higher.