protection dikes
Introduction
A dam is a construction to prevent the passage of water.[1] It can be natural "Natural dam (hydrography)") or built by humans; of earth "Earth (material)"), stone or concrete masonry, and both parallel and perpendicular to the course of a river or the edge of the sea.[2].
The purpose of a dam is to prevent the course of rivers from changing and to protect the area adjacent to the river or coast against flooding. Levees can be natural ridge structures that form along the edge of a river, or they can be a fill[3] or wall that regulates the water level. However, dams can be harmful to the environment.[4].
The ancient civilizations of the Indus Valley, ancient Egypt, Mesopotamia, China and Mesoamerica built dams. Today, levees can be found all over the world, and levee failures due to erosion or other causes can be major disasters, such as the catastrophic 2005 levee failures in Greater New Orleans that occurred in the aftermath of Hurricane Katrina.
Etymology
American English speakers use the word levee, from the French levée (from the feminine past participle of the French verb lever, 'to lift'). It originated in New Orleans a few years after the founding of the city in 1718 and was later adopted by English speakers. The name derives from the characteristic that the crests of the levee are higher than the canal and the surrounding floodplains.
The modern word dike or dyke probably derives from the word dijk in Dutch, the construction of which was already documented in the 1st century. The 126-kilometre (78.3 mi) Westfriese Omringdijk, completed in 1250, was formed by connecting older dikes. The Roman chronicler Tacitus mentions that the Batavian rebels drilled dikes to flood their lands and protect their retreat (70 CE).[6] The word dijk originally indicated both the ditch and the bank&action=edit&redlink=1 "Shore (geography) (not yet redacted)"). It is very similar to the English verb to dig.[7].
In Anglo-Saxon, the word dic already existed and was pronounced as dick in the north of England and as ditch in the south. As in Dutch, the English origins of the word date back to digging a trench and forming a bank next to it with the raised earth. This practice has resulted in the name being able to refer to both the excavation and the bank. Thus, Offa's Dyke is a combined structure and Car Dyke") is a ditch, although formerly it also had raised banks. In the English Midlands and East Anglia, and in the United States, a dyke is what a ditch") in the south of England, an indicator of the boundaries of a property or a drainage canal. When it carries a stream, it may be called a running dike, as in , which carries water from the stormwater drain"), Car Dyke, to the South Forty Foot Drain in Lincolnshire (TF1427). The Weir Dike is a seepage dike") at Bourne North Fen"), near Twenty") and next to the River Glen"), Lincolnshire. In Norfolk and Suffolk Broads, a dike may be a drainage ditch or a narrow artificial channel at the outlet of a river or wide for access or mooring, some longer dykes are named after him, for example Candle Dyke.[8].