Flood Control Dams

Since large number of natural fatalities, injuries and damage are caused by rapid flooding it is important to have flood control methods. Dams have been used for flood control since the first civilizations were formed.

Ancient dams

The Sadd-elKafara dam of Egypt was built around 2600 BC, about the same time as the beginning of the Pyramids. It stands 14m high and has a 113m crest. the lack of knowledge in hydrology and soil mechanics lead to the dam being over, designed. It had three distinct sections; the downstream shell made of rock, the upstream shell also made of rock and a centre core made out of fine silty sand and gravel. 17,000 blocks weighting 300kg each were carefully placement over the upstream and downstream walls to protect the dam against erosion. Construction problems were most likely encountered since it took longer than one dry season to built, and no evidence of any type of diversion could be found.

Romans the Romans built the Cavdarhisar dam near Kutahya in western Turkey to protect against raging floodwater. It was designed as a gravity structure with height of 7m, wide of 8m and a length of 80m. It also contained a large bottom outlet with a clear section about 11m2 that shows this dam was not designed to be a reservoir, not a flood control measure.

Medieval and Postmedieval Europe

Throughout the period few dams were actually built to for flood protection, however, many dams were built to cause flooding. Controlled flooding was used for transporting wood by fluming. Originally, the dams built for flum-ing were made from timber, however, few of these dams have any remains. from around the end of the 17th century the timber dam were replaced with masonry fluming dams. An example of a fluming dam is the Belcna dam in western Slovenia built in 1769. It was 18m high with a length of 35m, a crest width of 6.8m and a 12.4m base width. It was built of solid masonry and contained two outlets 5.1m in height and a width of 3.7m which allowed a large amount of water to rush out in a short time.

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