embankment dam![click to hear](/images/speaker.jpg)
Formed of mounds of earth or rocks, it is used mainly when the subsoil does not allow for construction of a concrete dam.
cross section of an embankment dam ![click to hear](/images/speaker.jpg)
drainage layer ![click to hear](/images/speaker.jpg)
Layer of permeable materials that is inserted into large-scale dams to collect infiltrated water.
sand ![click to hear](/images/speaker.jpg)
Granular material that is inserted between the core and the shoulder; it filters particles carried by the water flow to prevent erosion.
cut-off trench ![click to hear](/images/speaker.jpg)
Area of the foundation of the dam that is connected to the core; it contains impermeable materials to limit leakage and infiltration under the dam.
upstream blanket ![click to hear](/images/speaker.jpg)
Impermeable layer that consists of compact clay; it rests on the bottom of the dam to prevent infiltration.
foundation of dam ![click to hear](/images/speaker.jpg)
Natural terrain (such as rock, sand or clay) on which the dam is built.
downstream shoulder ![click to hear](/images/speaker.jpg)
Soil embankment that, together with the upstream shoulder, provides stability to the structure.
drainage blanket ![click to hear](/images/speaker.jpg)
Layer of permeable materials on the foundation of the dam; it collects infiltrated water and prevents erosion of the base of the dam.
upstream shoulder ![click to hear](/images/speaker.jpg)
Soil embankment located on the reservoir side; its mass provides stability to the dam.
upstream toe ![click to hear](/images/speaker.jpg)
Area where the upstream shoulder and the foundation of the dam meet.
downstream toe ![click to hear](/images/speaker.jpg)
Area where the downstream shoulder and the foundation of the dam meet.
berm ![click to hear](/images/speaker.jpg)
Horizontal ledge that stabilizes the upstream or downstream shoulder.
reservoir ![click to hear](/images/speaker.jpg)
Basin formed by the construction of a dam; it holds back a very large volume of water so that the flow rate can be controlled.
wave wall ![click to hear](/images/speaker.jpg)
Small wall located at the top of the upstream shoulder that protects the dam against waves.
pitching ![click to hear](/images/speaker.jpg)
Layer of rock or concrete blocks that covers the upstream shoulder to prevent erosion.
clay core ![click to hear](/images/speaker.jpg)
Central portion of the dam that is usually made of compact clay to make it watertight.
top of dam ![click to hear](/images/speaker.jpg)
Upper part of the dam; it rises above the water level of the reservoir by several yards.