Brief description

Primary use: Creating a reservoir for Water Supply during dry seasons.
Secondary uses: Flood control, hydroelectric power, irrigation, recreation.
Scale: Small (farm pond) to massive (Hoover Dam).

A barrier constructed to hold back water and raise its level, forming a reservoir used for water storage, irrigation, or electricity generation.

Use / Function

Hydrostatic Pressure: The dam wall resists the immense pressure of the water behind it.
Gravity: The weight of the dam itself anchors it against the water’s push (Gravity Dam).
Arch Action: The curved shape transfers water pressure to the canyon walls (Arch Dam).

Site Selection: Narrow valley with solid bedrock foundation.
Diversion: Temporarily divert the river (tunnels or channels) to work on a dry riverbed.
Foundation: Excavate loose soil down to solid rock. Grout cracks to prevent seepage under the dam.
Construction: Build the wall using concrete, stone masonry, or compacted earth.
Spillway: Include a channel to safely release excess water during floods to prevent overtopping.

Structure: Concrete, Stone, Earth (clay core), Timber (small dams).
Waterproofing: Clay core, concrete face.
Tools: Excavators (or shovels), cranes.

Earthfill Dam: Embankment of compacted soil with a clay core. Cheapest, suitable for broad valleys.
Gravity Dam: Massive concrete/stone wall. Requires strong foundation.
Arch Dam: Thin, curved concrete wall. Requires strong canyon walls.
Beaver Dam: Natural example using wood and mud.