Hydro jetting consists of a high-pressure hose with a specialized nozzle connected to a machine that pressurizes the water, producing a powerful stream that clears the drain. Hydro jetting is usually done through a cleanout, which is an opening that allows plumbers to clean out clogs. The water is forced down the drain, where it pushes grease, mineral build-up, hair and other debris through the drain. With a powerful enough hydro jet, tree roots can also be broken up. However, before using a hydro jet, a plumber typically inspects the drain with a small camera to determine if the pipe is damaged.