Random Smoke Testing – What Homeowners Need to Know

In the past few weeks, we’ve had a surge of customers in Oakland and Berkeley who have experienced “random city smoke testing” requiring them to have their sewer lines tested for compliance. This has caused considerable angst and confusion amongst homeowners.


Here’s everything you need to know about smoke tests, and what you should do if you have a random test administered on your home.

What are Smoke Tests?


The cities of Oakland and Berkeley conduct random smoke tests of residential sewer laterals—without the need for permission from homeowners. Notices are set to be delivered in the days leading up to the test but in just case you do not receive a notice or the notice arrives after the test has been performed, don’t panic. The tips in the following sections should help inform what you do next.

What exactly is a smoke test? According to the City of Berkeley:

“Smoke testing is the industry standard and an efficient, cost effective way to locate and identify leaks and the source of storm water infiltration problems in the sanitary sewer system.”

The reason cities are conducting smoke testing is to locate problem areas within the overall sewer system. The test identifies the sources of leaks and other problems in a sewer system, such as where storm water drainage is infiltrating the sewage pipes. This is done in order to avoid the environmental and property damages that occur when the city’s sewage system is overwhelmed by storm water.

These tests are scheduled to occur in select areas throughout the entire sewer system, which includes not only the main line running down the street, but also the private sewer laterals that connect homes to the public sanitary sewer main.

How Does a Smoke Test Work?


A smoke test is a sewer inspection method in which a non-toxic smoke, approved by the MSDSs Public Health Agency, is blown into manholes. The smoke makes its way through all the connected pipes in the sanitary sewer, helping to locate pipe leaks, broken manholes, cracks, uncapped lines, and more. Testers will also locate unknown sections of pipe (or sections professionals may not have realized were connected to the sewer), such as cleanouts, roof downspouts, and sump pumps. Certain types of discovered connections are actually illegal.

Regarding the smoke itself, the City of Oakland explains:

“The smoke is non-toxic and non-hazardous and is manufactured specifically for this purpose. It leaves no residuals or stains, and has no effects on plants or animals. The smoke should not enter your home, but if it does, it will have a distinct odor and should only last a few minutes with proper ventilation. Please note, all plumbing fixture drain traps must be filled with water prior to smoke testing.”

Homeowners are requested to pour water down all drains of plumbing fixtures that are not regularly used in order to fill the P-traps, which will help prevent smoke from entering the house.

During the smoke test, you may see smoke coming out of grass, utility boxes, cracked pavement, and more. Each test typically lasts about 15 minutes. Homeowners do not need to be home during that time, although it can be helpful to ensure the home is well-ventilated if smoke enters the home. You should also alert the testing crew if this happens.

What Happens After a Smoke Test?

All deficiencies are documented in a written report that should also include photos of the observed smoke. Smoke sources observed on private property will result in a letter from the city explaining the problems with an included deadline for correcting the issues, as these issues are the responsibility of the homeowner to fix.

From what we have seen so far, the cities tend to randomly smoke test a block of parcels on a given day and then send notices to homeowners after they have tested the lines. In some cases, the time lapse between the smoke test and the actual notice going out is large enough that homeowners are able to diagnose and address their problems by the time the notice arrives.

The challenges resulting from smoke test results will vary depending on the issues present in the system. Luckily, there are some fixes that are relatively simple to fix, including:

  • Disconnecting downspouts from sanitary lateral
  • Replacing a missing or broken lateral cleanout cap

However, more difficult corrections may also result. Issues that will usually require professional assistance include:

  • Cracked sewer laterals
  • Tree root issues
  • Re-routing damage from separating storm lines

sewer camera inspection is the next step whenever there is a more serious problem. The closed circuit TV (CCTV) will allow inspectors to discover/verify the true extent of the damage, helping to ensure a solution that truly solves your sewer problems once and for all. This is also important for the environment in our communities, as fixing these issues helps keep the Bay clean and preserve our overall local ecosystems. (Learn more about eco-friendly plumbing.)

What Should I Do?


If your neighborhood is experiencing random smoke tests, there is no need to worry. Follow the instructions given by the city in any notices they might send; and refer to paragraph three in this article, under the section “How Does a Smoke Test Work”? The paragraph instructs you to pour water down all drains of plumbing fixtures that are not regularly used in order to fill the P-traps, which will help prevent smoke from entering the house.

After your home is tested, you will receive communication regarding deficiencies in your line. (Since most homes in the Bay Area have relatively old sewer systems, most homes will have some sort of deficiency to fix.) The most important thing to do is follow the directions given and ensure you have fixed any issues by the given deadline.

Our team is happy to help translate and make sense of any issues reported in the notification you have received. We also offer video inspection, trenchless sewer repair services, and more. For individual assistance, get in touch with the experts at Pipe Spy.