It is a natural event or occurrence where a piece of land (or area) that is usually dry land, suddenly gets submerged under water. Some floods can occur suddenly and recede quickly. Others take days or even months to build and discharge.
When floods happen in an area that people live, the water carries along objects like houses, bridges, cars, furniture and even people. It can wipe away farms, trees and many more heavy items.
Floods occur at irregular intervals and vary in size, duration and the affected area.
It is important to note that water naturally flows from high areas to low lying areas. This means low-lying areas may flood quickly before it begins to get to higher ground. 

Flood is a overflow of water which used to submerge a dry land. For some days these floods have been disastrous in india and many other countries . It may occur due to accumulation of rainwater in saturated ground . Some floods can develop slowly while some are fast . Flood causes huge damage if houses and business .
When flood water recedes the land would be covered with mud and silt . These floods are more frequent in canada . The flood in china in 1931 is the deadliest flood that has ever occured . Floods can cause suh an extreme damage hat it can even submerge a whole country, for example : atlantis