Earthen manure storages are engineered structures used for the storage of liquid livestock manure. Generally these structures are designed so that about fifty percent of the structure is below existing grade and fifty percent is above. Certain circumstances such a high water table will require the structure to be built nearly all above grade. Conversely, it may be provident to build a deeper storage to accommodate gravity flow of the manure from a barn that is built at grade. Deeper EMSes still require some form of berming around them to prevent surface run-on.