Root intrusion is a problem everywhere. In 1977, more than 30 years ago, the United States Environmental Protection Agency stated that “Root intrusion is the single most destructive element facing sewer authorities today.”

To fully understand the problem of root intrusion into sewers you need to know why and how roots enter sewer pipes to begin with. Roots grow one cell at a time by splitting and growing. This is called hydrotropism. Hairs form on the roots as they grow and absorb moisture and nutrients. As these roots grow the stem is then coated by a root cap that works to protect the root.

The best environment for roots to grow in is cultivated soil where nutrients and moisture are abundant and easily accessible – which is pretty much the definition of a sewer pipe. Sewer pipes are laid in the ground and then back filled with stone and soil. The effluent in the pipe is warmer than soil outside the pipe. This creates condensation on the outside of the pipe near cracks and any