Pit latrines are the simplest types, sometimes just a hole in the ground covered with a floor plate. A dry pit does not penetrate the Water Table , while a wet pit does. Adding a Ventilating pipe is the key improvement of the ventilated improved pit latrine, a design that helps reduce unpleasant smells and fly problems. See Outhouse .
A water privy is a situation where a watertight tank receives the waste and sends it to an underground seepage pit or drainage area.
