Interested in a tile drainage system?
Check out the articles linked below to learn more.
Drainage 101
http://www.epa.gov/agriculture/ag101/cropdrainage.html
Planning a Subsurface Drainage System
http://www.extension.umn.edu/agriculture/water/planning-a-subsurface-drainage-system/
UW Discovery Farms Research
http://www.uwdiscoveryfarms.org/OurResearch/AgriculturalTileDrainage.aspx