Smoke Testing and Wastewater System Inspections 

For more information about smoke testing and wastewater system inspections in your area, please click on one of the links below.

Utilities have safely used smoke testing for many years. It helps to pinpoint problems that allow outside water into the sewer system and to identify system improvement needs.

During smoke testing, contract crews force smoke into sewer pipes through manholes. The smoke helps find cracks in pipes, uncapped customer lateral cleanouts, and prohibited connections that allow rain or groundwater in that can overwhelm the sewer system.

KUB sends letters to customers in advance of smoke testing to explain the process, and contractors leave door hangers two or three days before testing on a particular street. The letters and doorhangers include a Customer Support number customers can call if they have questions or concerns about the testing. KUB also notifies E-911 that smoke testing is being conducted, in case they receive inquiries. 

The smoke is non-toxic and non-staining, is not a fire hazard, and will not harm children, pets, or plants. Anyone with respiratory problems, however, should avoid breathing the smoke to prevent irritation. 

For your peace of mind, you might want to make other plans for a child, an elderly person, or an invalid who would otherwise be home alone during the testing. Use the number on the letter or door hanger to request notification immediately prior to the test to help avoid any confusion or alarm. 

For the test, KUB asks customers to run or pour about a pint of water into any garage or basement floor drains and unused sinks to fill the P-trap. The trap normally has water in it, but if the drain has not been used recently, the water may have evaporated. The water will help keep smoke from the testing from entering through the drain. 

During the test, don't be alarmed if you see smoke coming from vent stacks on buildings or holes in the ground. If the smoke enters your building, it may set off your smoke alarm. The smoke is harmless and should dissipate quickly - or you can open doors and windows to help ventilate smoke. 

If you poured water down any unused drains but smoke still enters your building, it may indicate defects in your plumbing. Note the location of the smoke, and call the KUB contact number provided. 

If you have questions about smoke testing in your area, please call KUB at 865-524-2911.