Dams Designed for Water Supply

It is impossible for a civilization to survive without a constant fresh water supply, since it is a basic need of all humans. In many parts of the world, the freshwater supply fluctuates from enormous amounts during the rainy season to long droughts during the dry season. for this reason dams were invented to store large amounts of water from the end of the rainy season until the end of the dry season, to ensure a constant supply of water.

Ancient Dams

The oldest dam in the world is the Jawa dam found 100 km northeast of Jordan capital Amman. This dam was built around 3,000 B.C. and was designed as a gravity dam. The design of this dam was quite complex considering that it was first dam to be built. It consisted of two dry masonry walls, with an earth core that acted as the water-retaining element. An impervious blanket was also provided in front of the upstream heel. A downstream embankment provided stability of the structure. The dam was later raised by 1m, using similar design methods as the original dam.

Romans

The Romans were the first civilization to use an arch dam. It is remarkable that the Roman did not use the arch dam earlier, since they had already become masters at employing it into their bridges and buildings. The first arch dam was constructed at Barcinas on Cubillas river 2km north of Granada, in southeast Spain. the arch design for this dam was not actually used to increase stability, but to lengthen the dam crest for easier passage of flood-water.

the first true arch dam was built by the Romans in the Vallon de Baume 4km south of Saint-Remy de Province in southeastern France. This dam was 12 high and 18m long, with a radius about 14m and a 73° central angle. It consisted of 1.3m upstream wall and a 1m downstream wall made out of masonry. The earth core between the two walls was about 1.6m wide, which means that the downstream wall was subjected to the entire load.

Medieval and Postmedieval Europe

The Roman standard of public fresh water supply continued throughout this period. the water supply for Istanbul in Turkey, during the beginning of the ear, was dealt with by many underground cisterns within the city. It was not until after the conquest of Istanbul in 1453 that the Ottoman Turks reconstructed some of the old Roman aqueducts. The first storage dam was built in 1560 on the remains of the Roman Belgrade dam. It was massive gravity dam, with a height of 15m and a base width of 56% of its height. The length of the dam was about 85m and had a 1.3 million m3 reservoir capacity. This dam also included a couple of unnecessary buttresses to add stability to the structure.

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