As a property owner, it is imperative that you sufficiently understand how your sewer functions and what could be a potential cause of your sewer backup. 
While sewage issues might not crop for long periods-even up to decades sometimes, do not mistake this invulnerability. It is only a matter of when you’ll have to deal with them, not if. 
In case you don’t know, there is no single definitive cause of sewer line problems. However, there are common types that are easy to spot and can be remedied with prompt attention. 
1. Tree Root Intrusion 
The intrusion of tree roots into sewer lines is a very common occurrence in the case of clay sewer lines or when you have trees growing above your underground sewer line. 
Nutrients and moisture present in sewer lines are like magnets to tree roots, especially during drought. Tree roots can easily grow through clay pipes to ensure their guaranteed survival.  
If you detect root Intrusion in your sewer line early, it can be easily mitigated.  
However, if you discover this Intrusion late, the nutrients that the sewer provides for intruder roots would have facilitated their rapid expansion and you might need to completely replace your piping. 
2. Broken/Collapsed Sewer Line 
Breakage or collapse of sewer lines may have already happened for months or even years before you encounter any backup in your home. 
It might start as just a crack or hairline fracture, basically once the line is compromised structurally. The situation will only worsen from thereon.  
Ultimately, running sewage will escape through expanded cracks or collapsed sections of the line to saturate into the surrounding earth.  
Eventually, the earth surrounding the sewage line will become oversaturated. Given this, sewage backup might be inevitable. The seepage of sewage into your environment will constitute a menace to your house sidewalk or roadway. 
3. Pipe Shifting 
This is majorly caused by the settling of the foundational earth that your sewage line is situated on. Foundational shifting, sinkholes, and even excess rainwater can cause earth below your pipe to give way or shift relatively, and this shifting can cause misalignment in your sewer pipe. 
In mild cases, these shiftings will only result in slope adjustment that will prevent the normal flow of sewage in the line. While in severe cases it can lead to line cracks, joint separation, etc. 
4. Back Pitched Pipe 
Sewage flows through sewers by virtue of gravity. This is achieved by pitching your house sewer pipe at an elevated height before linking it to the city sewer line. 
A back pitched pipe means that your sewage can’t flow into the city sewer system. This is mainly due to poor earth compaction prior to line installation, ground settling, or a bag installation. 
5. Pipe Blockage 
This most common type of sewer problem is sewer pipe blockage. Wipes, small debris, sanitary pads, diapers, kitty litter, tampons, and other “flushable” products can clog your sewer line. 
Clogged lines can easily be cleared using drain cleaners in mild cases. However, severe cases might require your contractor to use a large and heavy-duty drain snake or even a high-pressure water jet to remove your sewer blockage. 
Once you’ve cleared the sewer line, a post situational camera inspection is advisable for peace of mind. This can be achieved by using a suitable sewer camera for sale.