Leaks and breaks are a common but costly problem in underground sewer lines. Leaks and breaks happen in sewer lines for several artificial and natural reasons. Almost every sewer system will suffer from leaks, breaks and other issues at some point during its lifetime.
The presence of these problems in a sewer system does not only impede its efficiency, but it can impact its long-term durability. Sewer lines that suffer from unresolved leaks and breaks will decline faster and may have to be replaced sooner than expected, says TJC Management.
Broken sewer systems also pose a threat to the natural environment. A compromised sewer line can cause catastrophic flooding that will damage public and private property. Ruptured or fractured sewer lines may also contaminate soil and water bodies.
That is why you should perform professional sewer system testing for leaks and breaks periodically. There are many ways to test the integrity of a sewer system: dyed water testing, sewer camera inspection, flow monitoring, and more.
But SMOKE-TESTING is one of the best methods for evaluating the overall health of a sewer system. It is simple, fast, highly accurate and completely non-invasive. This post will explain what sewer system smoke-testing is and how it works.
What is sewer system smoke testing?
Sewer system smoke testing is a fairly simple process. As the name implies, it involves using smoke to detect problems in a sewer system. To test the integrity of a sewer system, non-toxic smoke is blown into the sewer system via a manhole or cleanout.
The smoke travels under pressure down the line, seeking escape through the paths of least resistance. If there are cracks or openings by which air can enter the sewer system, the smoke will find them and start to make its way out of the line through those openings.
Sewer smoke detection makes it easier to pinpoint problem areas in a sewer system. This method is capable of detecting minor leaks that can avoid detection when using other methods. Sewer system smoke detection is also used to verify that sewer line repairs have been done correctly.
Sewer smoke detection makes it easier to pinpoint problem areas in a sewer system. This method is capable of detecting minor leaks that can avoid detection when using other methods.
How sewer system smoke-testing works: a step-by-step explanation
Required equipment
Smoke-generating machine or blower
This will introduce smoke into the sewer line. It can be a squirrel cage blower or a direct-drive propeller blower. Squirrel cage blowers are more reliable. To be effective, the blower must produce a minimum of 1750 cfm (cubic feet of air per minute).
Smoke-producing material
Two types of smoke-producing materials are available – smoke candles and smoke fluids. Smoke candles are easier to use, have been around for longer and are more popular. Smoke fluids, on the other hand, are more affordable.
Preparing for the test
- The sewer line is cleared of any obstructions to ensure that air and smoke can flow freely through the system.
- All water sources are turned off, and any traps in the system are filled with water to keep the smoke from escaping.
- The sewer lines are camera inspected for the presence of vent stacks, manholes, etc.
- All vents and access points into the sewer system are closed except the access point where the blower will be positioned.
 Performing the test
- The blower is placed at the mouth of the cleanout or access point to allow the smoke to enter the sewer line easily.
- Depending on the type of blower and smoke-producing material, the material is ignited and placed in the appropriate position inside or outside the blower.
- When the blower is switched on, smoke from the smoke-producing material is drawn into the fresh air intake of the machine and channeled into the sewer system.
- That is done steadily for several minutes until the smoke starts to exit through any openings connected to the system.
- Pumping is continued to ensure it penetrates every part of the sewer line.
- The operators keep an eye out for smoke filtering from strange places, like walls, flooring or any place that should not have a connection to the sewer system.
- These areas are marked for further investigation and repairs. The findings of the test are documented.
- The operator turns off the blower and disconnects it from the access point.
- The water sources in the area are turned back on, and any residue left behind by the operation is cleaned up.
Benefits of doing a sewer smoke test
- Because it is non-invasive, sewer system smoke-testing saves time and money. Problems in the line can be detected without any need for costly excavations.
- Since there is no risk of damage to sewer pipes, sewer system smoke-testing is safer than methods like pressure testing.
- It is versatile and works equally well for large and small sewer networks.
- Problem areas in the sewer system can be identified very quickly and with a high degree of accuracy.
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