What is Dam ?

Monticello dam impounds the Putah Creek that can generate 56,806,000 kWh of power annually using 2x5 MW and 1x1.5 MW turbines.

During the 49th meeting of the French Association for the Advancement of Science held at Grenoble in 1925, a resolution was adopted that advocated the organization of a permanent international technical committee on large dams and France was asked to initiate its formation.

Du Jiang Yan is the oldest surviving irrigation system in China that included a dam that directed waterflow. It was finished in 251 BC. A large earthen dam, made by the Prime Minister of Chu (state), Sunshu Ao, flooded a valley in modern-day northern Anhui province that created an enormous irrigation reservoir (100 km (62 mi) in circumference), a reservoir that is still present today.

Apart from that, they displayed a high degree of inventiveness, introducing most of the other basic dam designs which had been unknown until then. These include arch-gravity dams, arch dams, buttress dams and multiple arch buttress dams, all of which were known and employed by the 2nd century AD (see List of Roman dams).

Hoover Dam (USA)
Hoover Dam is one of the most iconic dams around the world stretching between the American states of Nevada and Arizona. Originally called the Boulder dam, this colossal structure stands at a height of 221.4 m, with a base width of 200 m and a crest width of 14 m.

Thereafter, through the collaboration of the French Committee on Large Dams, the French National Committee, and the International Executive Council of the World Power Conference, a constitution was developed and adopted under the provisions of which the International Commission on Large Dams (ICOLD) was organized in 1928 as a self-governing affiliate of the World Power Conference

In Iran, bridge dams such as the Band-e Kaisar were used to provide hydropower through water wheels, which often powered water-raising mechanisms. One of the first was the Roman-built dam bridge in Dezful, which could raise water 50 cubits in height for the water supply to all houses in the town.

The Second ICOLD Congress Transactions [2] contain the best description of the early beginnings of ICOLD and of the United States’ participation in ICOLD, which was referred to at that time (1936) as the American National Committee

It's a concrete gravity-arch dam that was constructed with the purpose to control flood, provide irrigation water, produce hydroelectric power, store water, and for recreation.

Also diversion dams were known. Milling dams were introduced which the Muslim engineers called the Pul-i-Bulaiti. The first was built at Shustar on the River Karun, Iran, and many of these were later built in other parts of the Islamic world.

This “American National Committee” name appears to have been intended to include all of participating countries from North, Central, and South America. Subsequent ICOLD Congress Transactions were then examined to find any mention of when the formal organization called the U.S. Committee on Large Dams (USCOLD) was first mentioned.

The hydropower station houses various types of turbines like a 1x61.5 MW Francis turbine and 2x2.4 MW Pelton turbine, which produce an annual electrical output of 4.2 TWh.

Water was conducted from the back of the dam through a large pipe to drive a water wheel and watermill. In the 10th century, Al-Muqaddasi described several dams in Persia.

The first mention of USCOLD appears as a pencil note by Clarence E. Blee found at the front of the copy of the 1951 ICOLD Congress Transactions, Volume I (located in the Bureau of Reclamation’s Library at the Denver Federal Center in Lakewood, Colorado).

One of the biggest preparations done for the construction of Hoover Dam was the diversion of the Colorado River away from the site. To make this happen, four diversion tunnels were bored through the canyon walls - two on the Nevada side and two on the Arizona side

He reported that one in Ahwaz was more than 910 m (3,000 ft) long, and that and it had many water-wheels raising the water into aqueducts through which it flowed into reservoirs of the city. Another one, the Band-i-Amir dam, provided irrigation for 300 villages.

On the 1st of February, 1935, a few years after the Colorado River was diverted, a steel gate was lowered down to allow the water to take its natural course again.

In the Netherlands, a low-lying country, dams were often applied to block rivers in order to regulate the water level and to prevent the sea from entering the marsh lands. Such dams often marked the beginning of a town or city because it was easy to cross the river at such a place, and often gave rise to the respective place's names in Dutch.

Hydroelectric power is made when water passes through a dam. The electricity is made by a device called a turbine. These are made of metal coils surrounded by magnets.

That was the first time in history when the Colorado River was under the control of man. The dam impounds the Colorado River which consequently forms Lake Mead, the largest reservoir by volume (when full) in the United States.

For instance the Dutch capital Amsterdam (old name Amstelredam) started with a dam through the river Amstel in the late 12th century, and Rotterdam started with a dam through the river Rotte, a minor tributary of the Nieuwe Maas.

The magnets spin over the coils to produce electricity. Turbines are found in dams. The water going through a dam spins the magnets. The energy made is clean and pollution free. From this power we can turn lights on in our houses.

Three Gorges Dam (China)
Known as the world's largest hydropower dam, the Three Gorges dam stretches out 2.3 km to span and impounds the Yangtze river in the Hubei province in China.

The central square of Amsterdam, covering the original place of the 800 year old dam, still carries the name Dam Square or simply the Dam.

Dams and waterways store and provide water for irrigation so farmers can use the water for growing crops