Hydro jetting is a professional service that uses high pressure water jets to clean out dirt and debris in drain tiles. (the drain pipes set in the ground around your home to guide water away from your home into the sewer system) If your perimeter drains are not cleaned out every few years, tree roots and other things end up clogging them, which will lead to problems. If left alone too long, sewer drains collapse, or get so clogged they need to be dug up and replaced. In any case, hydro jetting is a much cheaper alternative to getting the sewer pipes replaced.