Hazard associated with flood is known as flood hazard. For instance flooding of farmland results in crop loss. Livestock, pets and other animals are often carried away and drowned. Furthermore, humans that get caught in the high velocity flood waters are often drowned by water.

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Dear Ahmed Sagban, a flood becomes a hazard when someone has been either injured or killed by it or if property is damaged. For example, when there are strong flood in an area that do not actually injure or destroy any properties, it is not technically considered a hazard, however, if this same flood injured a person or significantly damaged property, then it would be considered a hazard. This is also dependent on how much the damage affects the human activities that take place, a flood could damage a deserted building, this in some views would not be a hazard, but say if this building then put several people out of work, well then it would be considered a hazard.

You only need 6 inches of fast flowing water to take you off your feet, 12 inches to move a small car and 18–24 inches to move an SUV so there is a real danger of being swept away.

Hazards associated with flooding, and be divided into primary hazards that occur due to contact with  water, secondary effects that occur because of the flooding, such as disruption of services, health impacts such as famine and disease, and tertiary effects such as changes in the position of river channels. For more information you can visit the United States Federal Emergency Management Agency web site.