Waterproof is a town in Tensas Parish, Louisiana, United States with a population of 834 as of 2000 census. Waterproof is approximately seventeen miles north of Ferriday, one of the two principal communities of Concordia Parish. Poverty abounds in Waterproof, a delta town dependent on farming. Cotton is the most common crop, but corn and soybeans are also important. In 2008, drought destroyed much of the corn crop.