"Water distribution" is a work area in a certain arrangement of water according to certain rules, the most common is the uniform distribution of water in the work surface. Means to accomplish this task is called water distributor. Common water distributor perforated pipes, nozzles, filter head, rotating water distributor. For example, the sand filter in water distribution is by dry pipe - manifold - Cloth composed of water holes, the lower side of each branch pipe evenly arranged many holes, such as the diameter of the pitch, etc., filter backwash water from the dry pipe the branch pipe, and then by the branch pipe outflow hole up even wash filter sand. Rotating water distributor is able to rotate the perforated pipe, often used in water treatment.