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Sanitary Sewer Smoke Testing

Smoke testing is a way to locate openings in the sewer system that allow rainwater runoff to enter and can cause inconvenient and expensive sanitary sewer backups. Air combined with non-toxic smoke is forced into the sewer lines to disclose the location of leaks and connections to storm water systems. Smoke can be seen coming up out of the ground where there are defects in the lines. Smoke testing also identifies roof drains, patio drains and footing drains that are connected to the sewer system.

2016 Smoke Testing Locations

The City of Naperville has contracted with RJN Group, Inc. of Wheaton, Illinois, to perform smoke testing beginning this September and is expected to be completed by early October. If you live in an area that will be impacted by smoke testing, you can expect to receive a notification letter in the mail during the month of August. Additional notification will be provided by door hanger cards 24 - 72 hours before the smoke testing is to start in your area and s­­­igns will be posted at highly visible intersections when the crews are testing. 

Work is scheduled to begin Tuesday, September 6 and last approximately 5 weeks. Work will proceed as depicted on the Work Plan map.

view a map of the 2016 smoke test area

view a map of the 2016 smoke test work plan

Please note that this schedule is an approximation and that the timeline listed below is subject to change pending weather or unforeseen circumstances.

What Residents and the Public Can Expect

Smoke will not enter buildings unless there is defective plumbing or drain traps that are dried up. It is expected – and normal – for smoke to come out of the sewer vent stack on the roof of a home during the test.

Some sewer lines and manholes may be located in back yards. Homeowners do not need to be home during testing and field crews are not required to enter your business or residence. Work crews may need to access your back yard. If possible, please leave any gates unlocked. RJN Group personnel will be identified with uniforms and badges. 

Door hanger notification cards are being distributed to those impacted immediately prior to testing, and the public can expect to see signs posted at intersections when crews are testing in that area.

Timeline and Location

Work is scheduled to begin Tuesday, September 6 and last approximately 5 weeks. Work will proceed as depicted on the Work Plan map. Please note that this schedule is an approximation and that the timeline listed below is subject to change pending weather or unforeseen circumstances.  

  • Week 1 – green-shaded area – beginning Tuesday, September 6.
  • Week 2 – purple-shaded area – beginning on or around Monday, September 12
  • Week 3 – orange-shaded area – beginning on or around Monday, September 19
  • Week 4 – blue- shaded area – beginning on or around Monday, September 26
  • Week 5 – magenta-shaded area – beginning on or around Monday, October 3

view a map of the 2016 smoke testing area

view a map of the 2016 smoke test work plan

What To Do if You See Smoke

You should always feel free to call 9-1-1 in an emergency. If you believe smoke is entering your home from smoke testing, simply open a window and the smoke will dissipate quickly. Also, notify the crew that is conducting the tests by contacting a member of the crew on the street or the RJN Field Crew Leader at 630-639-1914. If the RJN field crew is no longer in the area you may contact RJN Group’s office at 630-682-4700.

The smoke is non-toxic, creates no fire hazard, leaves no residue, dissipates quickly and is harmless; however, those with respiratory issues may wish to take extra precautions such as leaving the home for a few hours until testing is complete. 

Additional Information

Read our Smoke Testing Q&A for answers to frequently asked questions about smoke testing studies. 

Visit the RJN Group website for more information about smoke testing in Naperville.  

Department of Public Utilities-Water