In the Earth, the Flood is the most dangerous destructive natural Hazards.It occurs mostly all over the world, when the water gets overflows.
TYPES OF FLOODS:
- The Riverine Flood occurs when there is extreme rainfall over an extended period of time.
- The heavy snow melting and ice jamming may be possible for Riverine Flood.
- By this Riverine Flooding, the areas may affect with causing dams and dikes.
- The Major two types of Riverine Flooding are, Overbank Flooding and Flash Flooding.
- The Flash Flood occurreddue to extreme heavy rainfall from thunderstorms.
- These occur with a great volume of water with short duration of time.
- When Compared to rainfall, the Flash flood generally occurs six hours to develop.
- The Storm Surge occurs at the time of intense low pressure system over the oceans.
- Because of the low pressure, the level of sea rises, and less air pressing below the sea.
- The Strom surge is nothing but, the water is pushed to shore by a hurricane.
- The flood occurs when the sea levels comes above the tidal limit and its depends upon the size and intensity of storm in an abnormal way
DAM FAILURE :
- The failure in Dams occurs due to manmade disasters like earthquakes, heavy rains, design defects etc
- It acts as an artificial barrier which can store liquid borne materials, impound waters in order for storage purpose and controlling of it
- The main causes for the failure are overflowing of river streams due to its increased volume of water and the capacity beyond the storage along deliberate acts
- It creates an warming of being damaged totally
COASTAL (SURGE FLOOD):
- The Coastal Flood which occurs mostly in the areas Coast of sea, Ocean and opened water area.
- Because of the extreme severe weather conditions, the Coastal flood occurs.
- The four main combination factors are Waves, Astronomical tides, Storm and relative mean sea level.
- It can also be caused by storm surge, sea level rise and tsunami
FLUVIAL (RIVER FLOOD):
- The Fluvial flood occurs, when the surface area washes into a river, and then the water overflows in the surrounding area.
- The major factors of fluvial flood are Rainfall Conditions, Ground Conditions.
PLUVIAL (SURFACE FLOOD):
- The rainfall or snowmelt is not absorbed into the ground level, the Pluvial Flood occurs.
- The Factors of Pluvial flooding are severity of rainfall, soil conditions like soil type,moistures,variations in vegetation’s, urbanization and sewer infrastructure such as overload of conveyance capacity
- Pluvial flooding relates to extreme downpour of rain saturation which results in over flow
- Pluvial floodingoccurs when an extremely heavy downpour of rain saturates drainage systems and the excess water cannot be absorbed
- The Urban Flood is nothing, the flood occurs in the Urban areas.
- It may be caused flash flood or coastal flood or river flood which affects in urban area.
- This flooding occurs due to flow of water into urban region which is faster than it can be absorbed into soil or reservoir caused by flash or coastal flooding