Flooded areas of land usually start off as very dry land. Floods are caused by heavy rains that pour to much water into rivers and other waterways. Making these natural channels unable to carry all the water. Rising water flows over or breaks the banks to the waterways causing the surrounding land to be flooded. Different causes of floods can come from masses of snow melting of tidal waves.
The type of land that is prone to flooding are broad and flat usually situated on the banks of a river or main waterway. Rivers that flood are regarded in three different stages. They are-
ONE- Water comes off the mountains, eroding the beds and banks of the river as it flows.
TWO- This type river travels through broad valleys which slows the current of the river down. If the current is slow it will transport less material down the river.
THREE- Flood-plain stage. Little if not any erosion takes place most of the material tha tis carried in the current is suspended and deposited to the form a flood plain.
Floods begin when soil and vegetation cannot absorb falling rain or melting snow, or when water runs off the land in such quantities that it cannot be carried in normal stream channels or retained in natural ponds and human-made reservoirs. Flash floods are the result of too much rain falling in too small an area, in too short a time. Flash floods frequently occur in seconds and minutes, while floods occur over hours and days. River Forecast Centers issue flood.
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