What’s In Your Sewer Line?

First, if your home was built before 1975, it’s highly possible you could have an outdated sewer line. We find all kinds of pipes in the Lowcountry. The following pipes were used until the mid 1970s (before the transition was made to PVC). Orangeburg pipe resembles cardboard covered in tar and typically collapses from the bottom.  Terracotta sewer pipes were made of clay and we find a lot of it. While the pipe itself holds up pretty well, the joints were often put together with mortar. The joints, over time, allow roots and dirt to enter the pipe and cause major clogs and sometimes pretty big sink holes. Cast iron pipe is another pipe we find often used as sewer line. We find these pipes in various stages of breakdown. The joints on most of the cast iron sewer lines from the 1970s and before mainly allow roots to enter the pipe. We also find that many old cast iron pipes have rusted to the point where holes have formed, allowing dirt, roots and even rodents to gain access to the pipe. 

We recommend replacing outdated pipe.

Second, as the years pass, sewer lines can settle and cause bellies in the pipe. A belly is a section of pipe that is lower than the rest of the pipe. Sewer lines should have a constant downhill grade to allow proper flow. When a section of pipe goes uphill, solids will buildup and eventually cause a clog. Bellies are a common problem. Grease buildup is a very common problem in a pipe belly.

What causes bellies in the sewer line? Could be that the line was installed improperly from the start. But we typically find that a large tree root pushes up on a section of pipe, making that section higher or lower than the rest of the line. Roots can grow very large in a 20 year span. We also find that the ground settles. Sometimes this settling is caused by the large tap root of pine trees finally rotting away allowing the dirt to wash in and fill the void, leaving your sewer line to sink a bit. We also find that driving cars and trucks over the area where your sewer line passes can cause the pipe to settle.

The only way to fix a belly in a sewer pipe is to dig that section up and replace it. The repair may also involve replacing the entire sewer line to ensure proper grade from the house to the tap.

Third, tree roots. We find many lines broken due to tree roots. Broken pipes allow dirt, roots and other debris to enter the sewer line. Many times the 2 sections of broken pipe will no longer line up, so sewage can no longer flow between the 2 sections of broken pipe.

Fixing a broken pipe, due to tree roots, usually involves replacing approximately 10′ of pipe to ensure that proper grade is maintained after the repair.

Fourth, bad pipe seals. Bad seals on outdated pipe joints is a given because they are just worn out. When PVC joints are not glued correctly, roots can grow in. Roots can be removed but they will come back within 6 months to one year. 

Fifth, grease build up. We find a lot of grease in sewer lines. This isn’t always cooking grease. Grease forms naturally from many things you put down your drains, especially soaps. Sometimes there are spots in the sewer line that allows grease to collect. Once grease attaches, it will grow until it eventually becomes large enough to cause a clog. Sometimes grease collects at joints in the pipe. Sometimes if the pipe is only level or slightly backgraded (without a belly) grease can build up. But grease always collects in a pipe belly.

Finally, we find a lot of things that should not be in a sewer line. Flushable wipes, paper towels and tampons are the primary culprits. These should never be flushed down a toilet because they do not break down in the pipe like toilet paper does. We also find rags, undergarments, diapers and construction debris. But if it can be flushed down the toilet, we’ve seen it.