**1. Introduction**

Each year natural disasters strike many parts of the world. Some parts are hit by heavy rains, some by heavy snowstorms, some by floods, some by mudslides, some by windstorms, some by hurricanes/cyclones/typhoons, some by heat waves, some by cold waves, some by snow avalanche, some by droughts, some by tornadoes, some by wildfires, some by earthquakes, some by lightening, some by volcanic eruption, some by tsunami, some by viral/bacterial outbreaks, and some by a combination of one or more of these disasters, such as heavy winds accompanied by heavy rains, drought accompanied by heat wave, cold wave accompanied by heavy winds, heat wave accompanied by viral outbreak, to name but a few. These natural disasters cause loss of life, damage to property, disruption in social and cultural fabric, environmental degradation, and imbalance in the ecosystem. To illustrate the impact of some of these disasters, **Table 1** lists yearly average global annual deaths by decade. It is seen that floods, droughts, and earthquakes cause more loss of life than other disasters. Of these three major disasters, floods and droughts are more common and can occur during the same year or at the same time but at different places in the same country. Further, it often happens that floods ravage one part of the country and droughts ravage other parts at the same time. An example is India where each year during the monsoon or rainy season, floods occur in the Northeast and North but droughts in the West at the same time.


**Table 1.**

*Yearly average global annual deaths from natural disasters.*

*Challenges in Flood Management DOI: http://dx.doi.org/10.5772/intechopen.99973*


**Table 2.**

*Storms impacts are costly (examples from the U.S.).*

Heavy rainstorms cause huge losses, as shown in **Table 2**. For example, Hurricane Harvey that struck the Houston area in Texas, U.S., caused damages worth US\$126.3 billion and 89 deaths, not to speak of untold misery and disruption in the community. It took a long time to recover from this hurricane. Along a similar vein, floods cause even more losses, as shown in **Table 3**. For example, floods that occurred in the Eastern U.S. on November 8, 1996, caused 187 deaths and damage worth US\$ 4.79 billion.



**Table 3.**

*Floods impacts are costly (examples from the U.S.).*
