When warm water flows through sewer pipes, water vapor escape and finds its way into the cooler soil surrounding the sewer pipe. The tree roots are able to sense the water and grow toward the sewer pipe. Once the root reaches the sewer pipe, it looks for cracks or any other area where the pipe connections may be loose which usually only takes place in a clay sewer pipe. 
Small hair-like roots begin to grow into the pipe where they meet all of the necessary nutrients a root needs to survive such as minerals, water & oxygen. Over time the roots continue to grow, eventually they hair-like roots expand into much larger roots causing additional cracks and complete breaks in the sewer pipe. As the entrance ways to the pipe become larger, additional roots will find its way into the pipe.
What do tree roots in a pipe mean for the homeowner?
If you do not take care of the hair-like roots in the early stages it may result in a large plumbing problem forcing you to replace your existing sewer line. A homeowner is responsible for maintaining the sewer pipe that connects your home to the city sewer which is located in the roadway in most cases. When roots enter into sewer pipes, anything that is put into the drain (tissues, oils, fats, grease) can get caught in the roots and will eventually cause a complete blockage of the pipe.
Is it possible to stop roots in the sewer pipe?
One of the biggest issues with roots in a sewer pipe is that it is hard to identify with the problem before it is too late. If you are maintaining your sewer line on a regular basis, there is a lot greater chance that you will become aware or avoid any major root problems. Once you become aware that your sewer pipe is flowing slower than usual, have a plumbing company come to your home and inspect exactly what is going on. The longer the problem continues without the proper care, the worst the problem may get.
You may also want to be aware of where you main sewer pipe is prior to planting any trees in your yard, there is no guarantee that a tree’s roots will not grow 10-20’ underground, the further the tree from your sewer the less of a chance that the roots will become a problem. You may want to select a small and slow growing tree when planning; small trees have less aggressive roots systems that are less likely to become a problem for your sewer pipe.
What can I do if roots have already begun to enter my sewer pipe?
If you already have roots entering your sewer pipe, there is a very strong chance that the roots will eventually cause a blockage in your sewer pipe if not tended to quickly. See our article on how often should a sewer be cleaned for additional details on preventing any additional damage to your sewer pipe.
