• Gravity dams are massive structure dam which is constructed of concrete or stone masonry. These dams are hold by the gravity to the ground.

• A gravity dam depends on its own weight for stability and is usually straight in plan although sometimes slightly curved.

• A gravity dam can hold a large amount of water. As they rely on their own weight, it is necessary to construct them on a solid foundation of bedrocks

Parts of Gravity Dam

• Heel: It keeps contact with the ground on the upstream side

• Toe: It keeps contact on the downstream side

• Abutment:It is the Sides of the valley on which the structure of the dam rest

• Galleries: Small rooms like structure left within the dam for
  checking operations.

• Diversion tunnel: Tunnels are constructed for diverting water before the construction of dam. This helps in keeping the river bed dry.

• Spillways: It is the arrangement near the top to release the excess water of the reservoir to downstream side

• Sluice way: An opening in the dam near the ground level, which is used to clear the silt accumulation in the reservoir side.

See figure 4.1