In the event of a sewer main blockage, a backwater valve is designed to keep sewerage water out of your basement.
The valve should be installed on the building drain just inside the foundation wall, under an access panel in the basement floor. The valve must be accessible even if the building drain goes through the wall.
All new homes in Quispamsis are required, under Sewerage Utility By-Law No. 005, to have a backwater valve installed on the building drain inside the foundation wall.