Environsmoke testmental Utilities wastewater collections conducts smoke testing as part of routine maintenance of the sewer lines in specific areas within the city.  These tests involve blowing harmless smoke into the sewer system to find cracks, breaks and other problems with the sewer lines that need repair.

During these tests, field crews blow air and smoke into the sewer system in the street and monitor where smoke escapes the system. Smoke may be seen coming from roof vents, building foundations, catch basins, clean-outs, down spouts, sewer laterals, or manhole covers. The smoke will not enter your home or business if it is properly plumbed, vented, and the water traps contain water.

These tests are harmless.  We use a product that is non-toxic and tested and approved by the National Institute of Occupational Health (NIOSH) and the Occupational Safety and Health Administration (OSHA), and has been used successfully for over 30 years throughout the United States.

Testing areas
July 8 through 12, 2019: Areas bounded by Washington Blvd on the East, All America City on the North, Main St on the South and Treasure Lane on the West.

Customer questions

What is the purpose of smoke testing?

The sanitary sewer system is a gravity system, designed to carry wastewater from your home to a treatment facility. During wet weather events, storm-related water can enter into the sanitary sewer system, causing increased flow that the system isn’t designed to handle. The purpose of smoke testing is to find potential points of inflow and infiltration in the sanitary sewer system that could lead to these high flows during significant storm events.

Smoke testing can also help locate the following:

  • Buildings that have downspout, yard or area drains connected to the sanitary sewer system
  • Points of groundwater or surface water that may enter the sanitary sewer system
  • Cross connections between sanitary sewer and stormwater systems
  • Defective sewer connections that potentially allow sewer gases to enter a building

What is a smoke test?

During smoke testing, crews use a high capacity fan to push a colorless, non-toxic smoke through the entire collection system, then monitor where the smoke is escaping the system.  The smoke will escape from the sewer system at points of connections, through roof vents, cleanouts and manholes. Smoke should not permeate from the middle of a yard, as this indicates a possible break in the line, which allows stormwater to enter the sanitary system.

What are the benefits of smoke testing?

Smoke testing is an efficient and cost effective way to locate and identify unauthorized water that is entering the sanitary sewer system. It also identifies leaks and breaks in private plumbing systems that potentially allow sewer gases to enter a residence.

Is the smoke harmful to me or my pets?

The smoke used is called LiquiSmoke™ and is non-toxic to humans, pets and houseplants. The smoke will not stain or leave a residue should it enter your home. This specific product has been tested and approved by the National Institute of Occupational Health (NIOSH) and the Occupational Safety and Health Administration (OSHA), and has been used successfully for over 30 years throughout the United States. While the smoke does have a low, but distinct odor, this odor disperses as fast as the smoke with no lingering smell.

Do I need to be home for the testing?

No. Smoke testing crews do not need to, nor are they allowed to enter your home.

If you have any concerns with the smoke testing, please talk to the smoke testing crew in your area or call us at (916) 746-1890.

As a homeowner, what do I need to do to prepare for smoke testing?

Water can evaporate from the drain traps of unused plumbing fixtures. Therefore, the day prior to any testing, property owners should pour water down all drains of plumbing fixtures that are not regularly used.

This will ensure that the P-traps are full to prevent smoke from entering the house through their sewage drainage system within the structure. P-trap refers to the shape of the drain pipe which holds water preventing air, odors and smoke from entering the residence.

p trap

How long does the smoke testing take?

Typically testing will only take 20-30 minutes per section, but you may see city staff in the area performing follow-up testing or notifications. Most homes will only be within the testing area for one or two tests. While testing, smoke may be seen around sewer manholes, sewer clean outs and roof vents.


Can smoke clog the sewer?

There is no way smoke can stop up a sewer. The smoke is made up of a vaporous substance similar to fog and will dissipate within a few minutes of the blower being shut-off.

Should smoke be venting from my neighbors roof?

Yes, roof vents are where the smoke should be seen or released. This is a normal occurrence and indicates that the smoke has filled the entire sewer in the area.

Will you notify public safety before testing?

Yes. Wastewater collections staff will notify Roseville Fire Department before we start work. If at any time you are unsure of the source of the smoke, please notify Roseville Fire Department by dialing 911.

Contact us

If you have any additional questions, please call our office at (916) 746-1890.

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