Backwater valves shall be installed in the branch of the building drain that receives only the discharge from fixtures located within such branch and shall be located below ground.
18-29-715.3 Material.
All bearing parts of backwater valves shall be of corrosion-resistant material. Backwater valves shall comply with ASME A112.14.1, CSA CAN/CSA B181.1 or CSA CAN/CSA B181.2.
18-29-715.4 Seal.
Backwater valves shall be so constructed as to provide a mechanical seal against backflow.
18-29-715.5 Diameter.
Backwater valves, when fully opened, shall have a capacity not less than that of the pipes in which they are installed.
18-29-715.6 Location.
Backwater valves shall be installed so that access is provided to the working parts for service and repair.
18-29-716 Flood Control.
18-29-716.1 Flood control devices.
Flood control devices in any house drain shall be vented and sized in accordance with this chapter. The total fixture units and any continuous or semicontinuous flow shall determine the size of the vent. No vent shall be less than 2 inches (50 mm) in diameter.