Sanitary Sewer Backups

A sanitary sewer backup can be a stressful and costly problem. Many sewer back-ups and overflows can be prevented through preventative maintenance.

Naperville homeowners are responsible for the maintenance of sanitary service lines and connections from their home to the main sewer line. The main sewer line is usually located in the street, across the street or in the parkway in front of your home. The city is responsible for back-ups caused by structural defects, such as a cracked pipe, and total sewer blockages located in the right-of-way.   

What to Do in the Event of a Back-up

Residents should notify the city before calling a plumber anytime they experience a sanitary sewer backup from a floor drain or sewer leaving the home. This is especially important when the back-up occurs during a heavy rainfall event. A representative from the Water Utility will determine if a problem exists in the city’s main sewer line. 

This service is provided at no cost to you and will save you the expense of calling a plumber if the main sewer line is the problem. If you are experiencing a sewer back-up from only one drain in your home, such as a bathroom sink or toilet, and all other drains are fine, this is an internal problem and you should call a plumber immediately.

If the city determines that the main sewer is clear, you will be advised to contact a licensed plumber at your expense. The city representative will measure and provide the distance from your home to the main sewer line.

Sump Pumps

To aid in the process of reducing rain-related sanitary sewer backups, residents should know where their sump pump is located and where it discharges.

Sump pumps should discharge to the exterior of the house. If yours does not, it is likely connected to the sanitary sewer system and needs to be disconnected and adjusted so that it discharges to the exterior of the structure where the water can flow to storm drains or swales.

If you are unsure where your sump pump system is discharging, please contact Sanitary Sewer Supervisor Mark Klossing at (630) 420-6741 or for additional information.

If your sump pump discharge creates a wet nuisance area in your yard, City staff is available to help you find a solution. Please contact the Stormwater Team at (630) 420-6100, option 4. Another way to improve drainage in your yard is to make sure storm drains on your property are clear from debris. This includes making sure mulch, leaves, rocks and other landscaping is not covering or blocking drains or inlets. 

How to Prevent Sewer Backups

Here are a few things residents can do to help make sure sanitary service lines remain unobstructed.


In Naperville, roots are the number one cause of sanitary sewer back-ups. Shrub and tree roots seeking moisture make their way into sewer pipe cracks. The roots may start out small, entering through a crack in the pipe, but as the tree or shrub continues to grow, so does the root. After time, this causes your sewer line to become obstructed with roots and waste builds up resulting in a sewer back-up.

If you continue to have problems with tree roots in your sewer, you should hire a plumber to cut them out yearly by rodding the sewer line. If you choose to replace your sewer line to alleviate the problem, take the time to get three price quotes since prices often vary drastically.

Paper Products

Paper towels, diapers and feminine products cause a great deal of problems in residential sewer lines. Unlike bathroom tissues, these products do not deteriorate quickly. They can become lodged in portions of your sewer line, causing a sewer back-up. Please dispose of these paper products in the garbage.

Flushable Wipes

In recent years, flushable wipes have become a prominent addition to retailers’ cleaning supply shelves. However, these wipes can weave together into a large mass once they are flushed, which can clog service lines, damage wastewater equipment and plug up wastewater pumps. The repairs caused by the wipes results in unplanned maintenance and additional costs to the utility.

Many times, calls to the utility from residents about sewer backups can be traced to homeowners’ lines that are clogged with flushable wipes, which results in unplanned costs to the customer. Please consider disposing of flushable wipes in your garbage can.


Avoid pouring cooking oil or other grease down the drain as it may cool off and solidify in the drain or the property owner's line. When this happens, the line constricts and eventually clogs. Pour grease into a heat-resistant container, let it cool and throw it in the garbage.