The first modern dam of world was completed in 1902 and is constructed on Nile River in Egypt at Aswan. It was designed primarily to control flooding of Nile River, to promote irrigation and for navigation along river.

Vega de Tera Dam in Spain was wrecked by heavy rains resulting in failure of structure due to faulty design and poor construction. The koyna dam in India was on verge of failure due to earthquake (in 1968).

Earn dams, Rock-fill dam, and combined earth and rockfill dam are all non-rigid dams. Timber dam, Steel dam, Arch dam, Buttress dam, and solid gravity dam are all rigid dams.

The name of Hoover dam was a political issue and it was first of all named as Boulder dam. Later it was changed to Hoover dam when Herbert Hoover became President of America. In 1933, President Roosevelt changed this name again to Boulder dam for 14 years and n once again name was changed to Hoover dam by Republicans which still exists today.

The Roosevelt dam was completed in 1911 on Salt River of Arizona (U.S.A). It was constructed with solid blocks of concrete which were of type known as Solid Masonry Gravity Dam.

A small dam constructed only to raise water level on upstream side for diverting it to canals is called a diversion dam. Nangal Dam is an example of a diversion dam. It is actually called a weir or a barrage.

In buttress dams, load is mainly transferred to supporting buttresses. The most common types of this dam are Deck slab type and multiple arch types. The multiple arch dams are used for higher dam heights.

Non-overflow dams are not designed to be overtopped. Sometimes it is combined toger with overflow dam to form a composite single structure. Overflow dams are designed to pass surplus water over ir crest and are often called as spillways.

This dam is a concrete gravity dam and is highest gravity dam in World with a height of 285 m. The primary purpose of dam is hydroelectric power generation.

The small dams which are constructed to delay and detain flow of floodwater are called detention dams. They are called check dams also. It is sometimes constructed to trap sediments and is often called debris dams.