Public Works Smoke Testing Program

What is Smoke Testing?

Smoke testing is an inspection of the City of Warrenton’s sewer system in which the sewer system is filled with a non-toxic, harmless, odorless smoke to find defects and faulty connections where excess rain water or ground water could enter.

Why is it important?

The sewer system was designed to collect waste from homes and businesses, not rain or ground water. This excess water takes up needed space in the sewer system, which could potentially cause sewer system overflows. The smoke test allows the City to find the possible problem areas that can cause this excess water to enter the sewer system.

When is the Smoke Testing going to occur?

Approximately 48 hours prior to smoke testing, door hangers will be distributed at each residence providing information regarding the procedure, names, and phone numbers of personnel to contact for more information.

What happens during the Smoke Testing?

During the smoke testing, the smoke will fill the sewer system and you may see smoke escaping through sewer vent pipes on roofs. The smoke is non-toxic, harmless, has no odor, and creates no fire hazard. If you have any infrequently used drains, please pour approximately 24 ounces in the drain to fill the trap before the smoke testing begins, which will prevent smoke from entering through the drain. Also, adding a small amount of vegetable oil will help slow down the evaporation of water in your drains. Additionally, many washing machine drain pipes do not have traps. To help prevent smoke from entering your building, tie a damp rag around the washing machine drain pipe opening. The smoke should not enter your house unless you have defective plumbing or dry drain traps.

What if smoke enters my home?

If the smoke enters your home it indicates there is a problem with the sewer plumbing in the home or a dry drain trap which means sewer gases are also entering your home. Contact a licensed plumber to make repairs. Remember, drain traps should always be filled with water to prevent sewer gases or odors from entering the building.

For more information, call Public Works at 636-456-3535.