The main sewer line is installed underground and therefore not visible. A main sewer line inspection involves sending a special camera into the sewer pipe so that its condition can be determined.

HERE IS A PIC OF THE VIDEO MONITOR
Approximately 90% of the main sewer lines in the Los Angeles area and surrounding cities have conditions occurring within them that require attention. There are many problems that can occur within the main sewer line, the most common being root intrusions that can cause blockages of the drain line and damage the pipe.
Also, many of the main sewer line pipes are made from materials that either wear out over time or can be damaged by seismic activity and root intrusions. Conditions or problems within a main sewer line can remain hidden and unknown for an extended period of time, thereby potentially causing further problems and more costly repairs. Having a main sewer line inspection can help to catch any current and future problems at an early stage, potentially saving money on repairs or replacements.
For more information go to www.SewerlineCheck.com or call (818) 951-7660

Great information Chris. Especially for a homeoowner down the road. I will check out your site.
Chris,
A good idea since it is costly to repair.
Thanks,
Ann
Buyer beware! You sure better check it out. We have more of the septic tanks and I ask all of my buyers for an inspection-city or county. It has saved many buyers from financial ruin I am sure.
Pretty cool!
As an inspector I often recommend this test in older homes where the water flow is poor. The results as expected are clogged or broken pipes.
I hadn't seen that before but my neighbor had a broken sewer pipe before he even got moved in.