The Mainline Fullport Backwater Valve's "normally open" design allows unrestricted sewage flow. Because of its Fullport design, it requires minimal homeowner maintenance when installed properly, and provides the best in backflow protection.

Installation of Backwater Valve

Retrofit Installation Of Backwater Valve

Testing the Unit

Mainline Fullport Backwater Valve Specifications

Access Box Specifications

How to Choose Which Valve I Need?

Maintenance Home Why a Mainline Valve How it Works Installation Links Contact Us Privacy Policy Mainline Backflow Products Canadian Home Builders' Association Mechanical Contractors Association of Alberta