What causes a sewer backup?
*Sanitary sewer overflows can be caused by a number of factors. They usually involve sewer pipe
blockages in either main sewer lines or service laterals (lines between buildings and the main line).
Causes may include pipe breaks or cracks due to tree roots, system deterioration, insufficient system
capacity due to residential or commercial growth, or construction mishaps. In home and office plumbing
systems, the main cause is accumulation of grease, tree roots, hair, or solid materials, such as disposable
diapers or sanitary napkins that are too large for wastewater pipes to handle. Such materials may cause
major backups in City lines as well as in residents’ lateral lines.
Is there anything I can do to prevent sewage backup into my home?
*Avoid putting grease down your garbage disposal or household drain. It can solidify, collect
debris and accumulate in the city lines, or build up in your own system.
*Never flush disposable diapers, sanitary napkins or paper towels down the toilet. They could
stop up your drains and may damage your plumbing system.
*If the lateral line(main sewer line) in your older home has a jointed pipe system, consider whether the roots of
large shrubs or trees near the line could invade and break pipes. It is a good idea to know the
location of your lateral line(main sewer line). You can call your local MUA for assistance in
locating your lateral line(main sewer line).
*If the lowest level of your home is below ground level, such as a basement floor drain, it may
one day be affected by a backup. One way to prevent sewage backup through such below
ground areas is to install a “back-flow valve” on the lowest drain(s). You can also use a
plumber’s test plug to close these drains when not in uselick here to edit.