Severe Winter Weather

Backflow valves are designed to block drain pipes temporarily and prevent flow into the house. This project requires a licensed contractor.

• Valves should be installed on all pipes that leave the house or that are connected to equipment that is below the potential flood level.
• If you have a sump pump, it may be connected to underground drain lines, which may be difficult to seal off.

Valves are available in a variety of designs that range from the simple to the complex. Your plumber or contractor can advise you on the relative advantages and disadvantages.

• A gate valve is one of the more complex designs. It provides a strong seal, but must be operated by hand. The effectiveness will depend on how much warning you have of impending flooding.
• Flap or check valves are among the more simple designs. These valves open to allow flow out of the house but close when the flow reverses. The valves do not provide as strong a seal as a gate valve, but they operate automatically.
• Some valves incorporate the advantages of both flap and gate valves into a single design.