Sewer Smoke Testing

Smoke testing is an efficient and cost effective method for locating leaks and deterioration of sewer pipes. The City uses smoke testing to determine areas in which the sewer system needs maintenance.

What is smoke testing?

Smoke testing is a common test method used to identify sections of the sanitary sewer collection system that have defects such as cracks, leaks or faulty connections that allow rainwater to enter this underground pipe network. Since the sanitary sewer system is only designed to handle sewage, the addition of rainwater/storm water causes many problems in the City’s collection system. The City of Kerrville intends to locate and repair as many of these rainwater connections as possible so that a heavy rain won’t overwhelm the sanitary sewer system or interfere with the operation of the wastewater treatment plant.

During the test, City of Kerrville employees will blow a dense white smoke into the sanitary sewer system. The smoke will escape again through openings such as holes in manhole covers and plumbing vent pipes located on or near rooftops. Smoke will also escape through defects such as cracks or breaks, open or broken cleanout covers, damaged or defective manhole frame seals, illegally connected roof or area drains and any other opening(s).

Why is it important to remove rainwater from the sanitary sewers?

Excessive rainwater in the sanitary sewer essentially “robs” the pipe of capacity. This capacity or space in the sanitary sewer pipe should be used to transport sewage to the wastewater treatment plant, not rainwater. If the sanitary sewer pipe is at or near the design capacity, there is simply no available room for this extraneous rainwater. During extended periods of rainfall or after even one heavy rain many pipes become surcharged or “over full”. Since there is no room for the extra water a backup or an overflow may occur. A backup causes wastewater to “backup” into a home or business connected to the sewer line. An overflow allows wastewater to escape from manholes or other openings into the environment

Why is The City of Kerrville testing my street?

The City of Kerrville has been inspecting the sewers and monitoring the flows throughout the city to find out where rainwater enters the sanitary sewers. The wastewater collection system that serves your house has been identified as an area that needs further testing to locate these sources of extraneous rainwater (inflow and infiltration) entering the system.

Is the smoke safe?

Yes. If you detect smoke on your premises, DO NOT BE ALARMED. The smoke is ODORLESS, NON-TOXIC AND NON-STAINING. It will dissipate quickly. It will not harm pets or plants or leave a residue. Open a door or window for ventilation and call one of the numbers listed to report the smoke.

What should I do to prepare?

 Smoke should only enter your premises if the traps in your home are dry or defective, or if you have uncapped or broken drain pipes. You may want to pour some water down your drains or unused plumbing fixture(s) to insure that the drain trap will be effective – run the water through these fixtures for approximately one minute.

Will anyone need to enter my home?

No City of Kerrville workers will need access to your home or business.

If you do find that smoke has seeped into your home you will need to contact a licensed plumber to make the repairs that are necessary.

Will I need to pay a fee for this service?

No. All testing is funded by the sewer utility fees paid by all residents and businesses in the city of Kerrville.