Tree roots growing inside sewer pipes are not an uncommon problem. They thrive on oxygen, so they will not grow in pipes that are filled with water. Rather, they will propagate in a warm, moist and nutrient-rich environment. The subsequent sewer damage can be quite staggering, not to mention costly. Wavin examines the causes and effects of tree root growth in sewage systems, and what we can do to prevent damage in our underground infrastructure.