Smoke Testing

Project Contact
Customer Service
Ph: 724-776-4806

How do I verify that the personnel are Cranberry Township Employees? 
All employed staff carry a Cranberry Township ID badge and drive appropriately labeled white vehicles.

What is smoke testing?

Smoke testing is a reliable sewer pipe testing method to indicate any fractured or collapsing segments, misaligned joints, missing cleanout caps or any illegal connections that are tied to the mainline collection system. These problem areas contribute to stormwater inflow and infiltration (I & I) in the sewer system. 

The combined flow between stormwater, groundwater, and sanitary wastewater can cause hydraulic and bio metabolic issues in the collection and treatment network. By maintaining the correct structural integrity, customers receive quality service and a reliable sanitary collection system.

Image source:

Waterline smoke test diagram

How will I be informed, if a smoke test will be performed at my residence?

  • A letter will be sent to all residents included in smoke testing. 
  • Residences will be tagged with a door-hanger several days prior to the event. 
  • You will receive a robotic phone call on the day before the test. 

To conduct the test:

  • Sewer and water staff seclude a particular portion of the sewer mainline pipe, sealing off the ends with plugs. 
  • The smoking machine is placed in a manhole, within the secluded section and begins blowing non-toxic, non-odorless smoke [MM2] into the lines using a small fan. 
  • Sewer and water employees walk along the test section, having a clear view of each residence, to spot any visual signs of smoke. 
  • If your home plumbing is adequate and the wastewater traps are full, no smoke should be released inside of your home. However, if smoke is spotted, our staff will document the source and nature of the problem and you will be notified. 
  • As a customer, you responsibility is limited to issues identified in the sewer lateral line or interior plumbing. The lateral line [MM3]  is considered as the privately owned pipeline, connecting the residence to the main line sanitary sewer. 
  • All mainline issues will be handled by Cranberry Township.

water pipeHow do I prepare for a smoke test?

  • We recommend that you run water into all drains within your home, filling the wastewater traps and preventing smoke from entering your home. 
  • You do not need to be home for the test to take place. 
  • The non-toxic smoke will not harm your pets if it does enter your home.

This video illustrates the use of smoke testing at a similar community in the Charleston Water System

What should I do if smoke enters my home?

  • If smoke enters the home, do not panic. 
  • Inform a sewer and water employee of the location of the smoke.
  • Open the windows and/or doors to ventilate the area and vacate the home. We ask that you vacate the premises due to the chance that there is an unrelated house fire. 
  • Smoke will dissipate on its own. 
  • Smoke is not hazardous.

What is considered an illegal connection?

All stormwater or groundwater connections that tie into the sanitary collection system are considered illegal per Cranberry Township’s Code of Ordinance . Examples are not limited to:

  • Downspout Connections
  • Outdoor Drains
  • French Drains
  • Sump Pumps

Questions and Concerns

Is the smoke harmful? The smoke is non-toxic, non carcinogenic, non corrosive, leaves no residue, and creates no fire hazard. 

Should I be home during the testing? You do not need to be home when the testing is occurring. Field staff will monitor the test from outside the home and take notes where needed. All pets are safe to stay in doors when the procedure is taking place.

Can the smoke testing activate the smoke alarms? Yes, smoke alarms may be activated during smoke testing. If possible, open windows and/or doors for ventilation. 

What should I do if smoke gets into the house? Open windows to allow ventilation and note the location of the smoke emission. Exit the building and notify Township smoke testing personnel in the area. 

Why do you recommend evacuating the building? As precautionary measure you are to evacuate the building if you witness smoke indoors in the rare case that there is a fire occurring at the same time that the smoke test is active. 

How long will the testing take? Smoke testing usually takes between a half hour to one hour to complete. Expect that field staff may be testing other parts of your neighborhood throughout the day. 

Where does the smoke appear? Smoke may be seen coming from roof vents, downspouts, building foundations, manhole covers or sewer cleanouts.