EMBANKMENT DAM

A dam structure constructed of fill material, usually earth or rock, placed with sloping sides and usually with a length greater than its height. Types of embankment dams include: (1) Earthfill or Earth Dam: An embankment dam in which more than 50 percent of the total volume is formed of compacted fine-grained material obtained from a borrow area (i.e., excavation pit); (2) Fill Dam: Any dam constructed of excavated natural materials or of industrial waste materials; (3) Homogeneous Earthfill Dam: An embankment dam constructed of similar earth material throughout, except for the possible inclusion of internal drains or drainage blankets; distinguished from a Zoned Earthfill Dam; (4) Hydraulic Fill Dam: An embankment dam constructed of materials, often dredged, that are conveyed and placed by suspension in flowing water; (5) Rockfill Dam: An embankment dam in which more than 50 percent of the total volume is comprised of compacted or dumped pervious natural or crushed rock; (6) Rolled Fill Dam: An embankment dam of earth or rock in which the material is placed in layers and compacted by using rollers or rolling equipment; and (7) Zoned Embankment Dam: An embankment dam which is composed of zones of selected materials having different degrees of porosity, permeability, and density.