Dam break
With a dam failure or dike breach a dam or a dyke by water or mudslides, such as sedimentation , damaged or destroyed. It is characteristic that a small leak increases rapidly, more and more water or mud flows over the dam or dike and further destroys it. A chain reaction occurs .
description
It is the failure of a dam or a dike . This is a problem in hydraulic engineering . The imprecise name does not mean that something will break. Rather, a dam break is usually initiated by the soil being softened either by excessive hydrostatic pressure or by internal damage to such an extent that it can no longer transmit the shear stresses and is pushed away horizontally. A dam can also break in an earthquake due to soil liquefaction .
Protective measures
If a dam threatens to break, attempts are made to reinforce it with stone slabs or textile material. In acute cases, the land side is reinforced with sandbags . Another measure is weighting down by adding soil.
Hazards
Some animals like the muskrat , but also beavers and rabbits , endanger dams by hollowing them out when building caves.
Known dam breaks
- September 18, 1916 - Dam on the White Desse , Bohemia, today the Czech Republic
- December 1, 1923 - Gleno Dam at first flooding, technical failure; possibly stop
- June 29, 1925 - Dam burst at Sheffield Dam , USA, due to earthquake
- Jan. 31, 1953 - Storm surge on the Dutch, British and parts of the Belgian coast
- Dec. 02 , 1959 - Barrage de Malpasset , France, rupture , about 400 dead
- February 16, 1962 - During a large storm surge , Hamburg-Wilhelmsburg went down due to dyke breaches , around 300 people died.
- July 9, 1987 - Heavy monsoon rains caused the dam of the Amaravada water reservoir in the Indian state of Telangana to burst . The masses of water tore away a railway bridge over which a train was passing; 70 people died .
- July 24, 1997 - Dike breach in the Ziltendorfer Niederung in Brandenburg during the Oder floods in 1997
- January 30, 2000 - The breach of the Baia Mare dam in Romania triggered an environmental disaster.
- August 12, 2002 - The Glashütte retention basin broke during the Elbe floods in August 2002
- August 30, 2005 - Hurricane Katrina did not destroy the levee in the city of New Orleans , which is largely below sea level, but the walls of two canals from Lake Pontchartrain , so that the city was flooded over a large area.
- October 4, 2010 - Kolontár dam breach near Kolontár in western Hungary . 150 people were injured and 10 died. 40 square kilometers were affected when around one million cubic meters of red mud flooded the country.
- November 5, 2015 - Dam breach in Bento Rodrigues , Brazil : Dams of a sedimentation basin of an iron ore mine collapsed. 16 people died; 32 million cubic meters of mud flowed over several rivers towards the Atlantic.
- January 25, 2019 - When the Brumadinho dam broke, the dam of a sedimentation basin at an iron ore mine in Brazil broke again. Hundreds of people missing.
Forecast and calculation of dam breaks
Since the failure of dams can never be absolutely ruled out despite high safety devices, the dam break forecast for large storage facilities in Europe is required by the authorities. Various models are currently available for this. The complicated process of erosion fracture is represented most precisely with numerical models. One example of this is the 2dMb model from ETH Zurich . This program can record both the outflow (hydraulics) and the erosion of dam material (erosion). The aim of such simulations is the outflow hydrograph of the dam breach. This allows the further course of the tidal wave to be calculated and the destructive force of a dam breach to be estimated.
metaphor
Dam break is also often used metaphorically . A dam is said to have broken if something that has been strictly adhered to for a long time is not followed once. The concern is that after this one injury, many more injuries can follow, as if the first injury had broken a small piece of the dam, destroying the entire dam.
