What Causes Floods?

Floods occur when there is an overflow of water and the water submerges the land. Floods occur whenever the water exceeds the capacity of the container so it overflows from the boundaries. Some of the causes of flood include heavy rainfall like in monsoon season that overflows the dams, rivers and lakes. Another cause is the melting of snow on glaciers that overflows the rivers and they submerge the nearby land. In coastal areas the main cause of floods are the sea tides are high and are brought to land by heavy winds.

Floods are caused either because too much rain falls in a specific amount of time, which leads to drainage systems being overwhelmed.  Or barriers such as a river bank may give way due to too much rainwater and this will cause flooding. Abnormal tides particularly combined with heavy rainfall can cause a river to burst its banks.
Flash floods are caused by too much water coming down in too short a time, with too much water to drain away effectively.  Flash floods are sudden and tend to drain away quicker than other floods.

Floods may also be caused as a by product of a tsunami, earthquake or even hurricane (although it is quite rare for hurricanes to cause floods).

Parts of the UK are more liable to flooding, with over 2 million people living in a zone which is in danger of flooding.  Fears are increasing tat due to global warning and subsequent weather changes, this figure may increase substantially over the next fifty years.

Although rivers are a great source of life and some of the most prosperous ancient civilizations depended heavily on rivers for their economy, they have their share of drawbacks too, which were existent both in the past and the present, although today their impact has mitigated by the incorporation of some precautionary techniques.   For starters, rivers cause floods, which becomes an overgrowing ordeal for residents, farmers and transport authorities equally.  Some of the major causes of floods are illustrated below:

The season of summer is characterized by the melting of snow, which swells the volume of the rivers and results in floods.  Besides the melting snow, another source of additional water is the heavy monsoon rainfall.  In addition to that, the cutting down of trees (that is generally for commercial purposes) on the foothills contributes towards augmenting surface turn-off that becomes the  cause of floods.  Also the embankment network along the rivers is a weak one that is built to prevent flood risk.

Too much rain and if there is a blockage in the drainage system

Intense rainfall, urbanization or lots of buildings, heavy storms, pollution, poor drainage systems, overflow of water and melting of snow in glaciers causes flood in different parts of the world.

It could have been caused by the outbreak of global warming, which would leads to the flooding of coastal areas and rural areas, and even leads to few big cities being completely submerged under water. Deforestation, pollution, melting of ice caps, breaking of the dams. It also could have been caused by volcanic eruptions, tsunamis, earthquakes and many other natural disasters, or even tropical storms.