Backwater valves and backflow valves are two types of plumbing valves that serve different purposes.
A backwater valve is a device installed in the main sewer line to prevent sewage from flowing back into a building in the event of a sewer backup. It works by automatically closing when sewage flow reverses, preventing any sewage from entering the building. This type of valve is typically installed in the basement of a home or business, and is designed to protect against damage caused by sewer backups.
On the other hand, a backflow valve is a device that prevents contaminated water from flowing back into a clean water supply. This is important to prevent backflow of dirty water from appliances like washing machines or dishwashers, which can contaminate the clean water supply. Backflow valves are typically installed in the water supply lines of buildings, and are required by law in many areas.
While both backwater valves and backflow valves are important plumbing valves that help protect buildings and clean water supplies, they serve different purposes. A backwater valve prevents sewage backups, while a backflow valve prevents contaminated water from entering a clean water supply.