Tree roots are remarkably adept at working their way into poorly sealed pipe joints. Once inside, they'll fill the pipe with multiple hair-like root masses at each entry point. The root masses act like nets and soon catch toilet tissue, grease, and waste flowing from the toilet and sink drains, resulting in reduced flow and slow drains. A complete blockage will eventually occur if the roots aren't removed or impeded. Once a complete blockage occurs, households can experience water and sewage damage from overflowing toilets, sinks, and especially from appliances like washing machines and dishwashers. The water must go somewhere, and if it can't go down the drain, it'll flow out of the appliance or plumbing fixture and onto the floor.

If left unchecked, roots inside pipes continue to grow and expand, putting pressure on cracks or pipe joints. This slow, deliberate force will further damage the pipe. It may result in a total collapse, requiring repair or replacement of the sewer line. Unfortunately, homeowners are usually responsible for the cost of repairing a broken sewer pipe beneath their yards. Cities and municipalities are only responsible for the sewer mains beneath streets, which residential sewers flow into.