What Are Levees and Dams Made Of? Materials & Construction Types

Both levees and dams are engineered barriers for water control, but they serve different purposes and use distinct materials and designs.

Levees (Flood Embankments)

Built parallel to rivers to prevent flooding of adjacent land.

• Compacted Soils: Sand, clay, loam—locally sourced, compacted for low permeability.
• Rock Armor: Stones, boulders, riprap for erosion protection on the river-facing slope.
• Concrete/Steel: Used in high-risk urban areas or where space is limited (floodwalls, sheet-pile walls).

Dams (Water Retention Structures)

Built across rivers to impound reservoirs. Major types:

Embankment Dams (Most Common)

• Earthfill: Compacted soil (clay core, sand/gravel shells)
• Rockfill: Compacted rock fragments with impervious core or upstream face

Concrete Dams

• Gravity Dams: Massive concrete/stone relying on weight to resist water pressure.
• Arch Dams: Curved upstream; transfer load to canyon walls. Ideal for narrow gorges.
• Buttress Dams: Sloping deck supported by buttresses; uses less concrete than gravity dams.

Material Selection Factors

• Foundation geology
• Seismic risk
• Available materials and cost
• Hydraulic loading and reservoir size
• Environmental regulations