Create an Account - Increase your productivity, customize your experience, and engage in information you care about.
Every water fixture in your house has a vapor trap. This "U" shaped pipe is clearly visible under sinks, and is present in some form on all lines draining to the sanitary sewer system. The "U" shape holds water, preventing gases from backing up from the sewer into the house through the drain.
Show All Answers
Blockages can occur for two reasons. The first is the accumulation of material inside of the line. Draining unsuitable substances through the sewer, such as kitchen fats and greases or sand, clay or mud, can cause a buildup and blockage in otherwise properly constructed sewers. However, the proper operation of a sanitary sewer line requires that the line be constructed "on grade", that is with a consistent slope. High or low areas along a line will cause small amounts of greases soap scum and other material to accumulate, eventually causing a blockage. "Clean Outs" provide the homeowner or sewer drain contractor an access point for sanitary sewer line maintenance.
Any crack or break in the building sewer allows ground water to enter the sewer. These leaks not only create blockages for the homeowner, but allow clean water to enter the sanitary sewer system. Once in the system, this clean water becomes sewage and must undergo all of the expense of sewage treatment and disposal. Similarly, the discharge of water from a water to air conditioner contributes a large amount of otherwise clean water to the sewer system. A single water to air unit can contribute an amount of water equal to 40 single family homes. For these reasons, the discharge from a water to air unit into a sewer drain is prohibited. Homeowners with cracked or broken sewers, or deteriorated pipe may be required to repair or replace the sewer line to eliminate these potential problems. You can contact the Environmental Protection Agency for more information.
Sewage has a natural tendency to produce odors. All sewers have some odors. The plumbing system in your home is designed to prevent these odors from entering the house. If you are experiencing odors indoors, it is likely that there is a problem with the vapor trap.
All houses have plumbing vents that extend through the roof. These vents allow air to flow both in and out of the house plumbing system, helping water to flow through the pipes. Working in combination with the vapor traps, gases from the sanitary sewer system are vented safely through the roof.