Red Seal Plumbing Exam Prep 2026

A backwater valve is a plumbing device that prevents sewage from flowing back into a building. It is typically installed in the building drain, at the point where the pipe exits the structure and connects to the sewer line. The valve is designed to remain open, allowing sewage to flow out of the building and into the sewer line. However, in the event of a blockage or sewer backup, the backwater valve will close to prevent sewage from backing up into the building. Therefore, the correct answer is that a backwater valve is normally open. Option A, normally closed, is incorrect because the valve is designed to remain open unless there is a backup. Option C, periodically inspected, is incorrect because while it is important to have the valve inspected for proper functioning, it is not a requirement for the valve to be installed. Option D, electrically powered, is incorrect because backwater valves do not