Soil drainage, understood as the removal of excess water from the soil matrix, plays an integral role in the environment and land use. It affects plant growth, soil biota, the leaching of nutrients and other solutes, the release of greenhouse gasses and the risk of soil compaction and surface erosion. Insufficient soil drainage is a major agricultural concern and can be caused either by a high groundwater table or the stagnation of water in the soil matrix. In Denmark soil drainage is described by five drainage classes from 1 (i.e. very well drained soils) to 5 (i.e. very poorly drained soils). Despite efforts to map the soil texture and taxonomic classes of Denmark, soil drainage classes have not been mapped yet.