When dealing with a sewer line clog, trees are the last culprit you'd possibly suspect. Unfortunately, sewer line issues caused by tree root intrusion are quite common, especially among those who own older properties with established tree growth. The following provides an in-depth explanation of how tree root growth can cause problems for your plumbing and how to combat invasive growths.
How Roots Invade Sewer Lines
Clay, cast iron and ABS plastic are three common materials used for residential sewer pipe. Clay pipes were once popular for sewer pipe installations and can still be found in homes built prior to the 1980s. These types of pipes are especially vulnerable to root intrusion due to their relative fragility. Roots can intrude into these pipes through loose joints or broken portions of pipe. Once inside, the roots can expand until they eventually break the pipe.
Cast iron pipes are stronger than clay, but cast iron is vulnerable to rust and corrosion. Exposure to unusually acidic soil can create external corrosion, while exposure to sulfuric acid in sewer line waste can create internal corrosion. Tree roots can infiltrate through the various holes created by rusting sewer pipes, allowing the roots to thrive on their new nutrition source.
Thanks to their flexibility, ABS pipes are less prone to breakage and they're resistant against many corrosive chemicals. However, poorly fitted joints and joints with failing adhesives can open the door to root intrusion.
Fixing the Problem
Taking care of an invasive tree root in your sewer line can be a lengthy and expensive process, especially with the possibility that part or all of the sewer line may need replacement. To cut down on mistakes and unnecessary labor, your plumbing contractor may conduct a video inspection of the pipe before performing any further work.
If the root intrusion is minor and the sewer pipe is relatively intact, your contractor may use a drain cleaning tool to remove the root and other debris from the pipe during a sewer cleaning. These tools range from metal cutting heads attached to a water-powered plumber's snake to high-pressure water jets that use varying amounts of water pressure to cut through and flush out roots.
If the root intrusion has blocked or destroyed much of the pipe, a complete excavation, removal and replacement of the pipe may be your only option. According to CostHelper, a full sewer line replacement could cost up to $25,000 depending on the replacement methods used.
Prevention is the best policy, especially when it can stop errant tree root growth before it becomes a major problem for your home and a financial burden for your household. Natural biocides like copper sulfate or potassium hydroxide can stop current tree root growth and prevent further growths from occurring in the vicinity of the pipe. In most cases, it may take several weeks of treatment before the offending roots stop growing.
Placing physical barriers around the sewer line can also prevent roots from intruding into the pipe. For example, a protective mesh screen can help slow or even redirect root growth. Other barriers include highly compact layers of soil surrounding the sewer line and buried strips of wood or metal alongside the pipe.
Directly managing the roots near your sewer line is another step you can take to prevent root intrusion. This usually involves targeted digging and cutting of the roots. In some cases, you may need to completely remove the offending tree and landscape the area with new grass or bushes and shrubs featuring shallower root systems. These preventive tips can help eliminate the need for extensive repairs and replacement of your sewer lines.