Smoke Testing

Project Overview

2022 Sewer Smoke Testing - The test will last approximately thirty minutes in each location.   

Location: Approximately between East 1st Street & East 11th Street, and between 35th Avenue East & 40th Avenue East (map of location below).

What is the process and what will I see during smoke testing?

City workers direct the smoke down the City sewer main (pipe), usually located directly below an alley or road, which is connected to a home or building’s private building sewer lateral (pictured). If the building sewer lateral has no defects, the smoke will flow from the building sewer lateral to the vent stack (pictured). If the building sewer lateral has defects, such as cracks or malfunctioning joints, the smoke will seep through those cracks and up through the soil (pictured). 

Defects in the private building sewer lateral, showcase that there could be potential sewer leaks and defects. If smoke enters your home or building, dangerous sewer gases might also be entering inside your home or building. You may have dry drain traps or improper plumbing.  It may be necessary to have a licensed plumber inspect your home or building’s plumbing.

What is the smoke and is it harmful?

Smoke used does not create a fire hazard or present a health hazard; it is white in color, will not stain or leave residue, has a very mild sulfur odor, and is tested to be proven safe. Smoke should not enter your home or building unless there is defective plumbing or a malfunctioning “P” trap.  

What is the purpose of smoke testing? 

Smoke testing is conducted to identify and document deficiencies by blowing non-toxic smoke through the collection system (sewer). It’s a non-invasive technique that simulates how rainfall and high-ground water can get into the sewer system. 

Smoke testing can identify sources of inflow:

  1. area drains
  2. abandoned building sewers
  3. sewer manholes with perforated covers or leaky seals
  4. roof downspouts
  5. illegal connections
  6. storm drain cross connections

Smoke testing can also detect sources of infiltration such as:

  1. pipe cracks
  2. open or offset joints
  3. open connections
  4. faulty building sewers 

2022 Smoke Test Boundary (Reduced)


City workers will continue to be conducting sewer system tests located in the area found on the above map.  Over 70% of the testing was completed in August.  Due to wet weather, more time is needed for completion.  Smoke testing will be rescheduled for another date during the end of August/beginning of September dependent on the weather.  Please keep an eye out for posted signs in your neighborhood and updates on the City of Superior website.

Public Announcement

City workers will notify residents/businesses before they begin working in their neighborhood by placing door hanger cards on their doors. Also, check the City of Superior Facebook page for updates @

The testing does not require the City workers to enter homes or businesses, and residents do not need to be home during the testing. If you are at home during the test, please contact the crew if any smoke enters your home. If you are away during the test and discover smoke in your house upon returning, call the number below. All public safety authorities will be notified.

Check out the educational brochure on smoke testing right here!


Questions or concerns regarding the smoke testing should be directed to the City of Superior Environmental Services Division of Public Works at (715) 394-0392 or