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FLOODING
DEFINITION OF FLOODING
Flooding can be defined as an overflowing of water onto land that is normally dry. It also occurs when there is more water on the surface of the land than it can take. This may lead to river overflowing its banks.
Erosion Endangers Shore Home
Natural forces such as wind, rain, and temperature cycles continually erode the land. This Chesapeake Bay home was built on a cliff that has undergone severe erosion. Many people battle erosion by planting grass and trees to form a strong root system or laying down netting to keep rock and soil from washing away.
Causes of Floods
Deforestation: When large areas of forests near the rivers are cleared, the land may be used for settlement, roads and farmland. Less vegetation protects the soil, the soil is quickly lost to rivers and sea. This raises the river bed, so the river overflows its banks easily, and then flooding occurs
Poor water management: when the dams are poorly constructed or maintained, they can easily collapse and these results in flooding.
Population pressure: Because of large amounts of people, more food, wood, etc are needed for consumption; thereby leading to over-cultivation of lands which le ad to erosion and increases the risk of flooding.
Glacial Deposition
Glaciers, such as this icy formation in Switzerland, deposit materials as they grow and shrink. Glacial deposition is a process that includes the deposits laid down by the glaciers and the landforms that these deposits form. Glaciers transport till, materials such as rocks, sand, and clay. Till collects to form features such as terminal and lateral moraines.
Amount of rainfall: The amount and intensity of rainfall determine the amount of run-off on the land and this will determine the amount of water available for flooding to occur.
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