Tile Drainage

Abstract Tile (or relief) drains are porous pipes buried approximately 1 m beneath the surface of the soil. These pipes drain excess water from the land into nearby water bodies, most typically cisterns, open ditches, or streams. The most common use of tile drainage is to improve agricultural production by draining excess moisture from the plant root zone and allowing cultivation normally saturated soils. Subsurface tile drainage also lowers the water table and reduces soil salinity. Many of the world's productive agricultural areas, including 25% of the cropland in the United States, require artificial drainage. The area drained by subsurface drainage systems in the United States has increased since 1900 from less than 5 to almost 30 million hectares.