Agricultural producers have been using subsurface artificial drainage since the late
1800’s. This allows areas that would have otherwise been deemed unproductive for
agriculture to grow substantial yields. Data and records on drainage tile location are not
consistent. In recent years, researchers have turned to aerial photography to map
functioning drainage tiles. Knowing the location of drainage can allow more accurate
hydrology studies. This research explores photo interpretation and compares it to remote
sensing and decision tree analysis techniques to delineate subsurface agricultural drainage
tiles in the Eagle Creek Watershed in Iowa, USA.