15.2.1. Factors Influencing the Design of an Embankment Dam (i) Materials Available for Construction One of the main advantages of an embankment dam is the availability of construction material free of charge at or near the dam site. Depending upon the type of material available, the designed embankment may either be a homogeneous earth dam (when the soil available is impervious), a zoned earth dam (when both pervious and impervious soils are available) or a rock-fill dam (if rock is available and impervious material is not). The design may also incorporate use of materials from required excavation (for spillway construction) for reasons of economy.
