Question

causes of floods:
Severe winds over water

Answer 1

Causes of Floods. Floods are caused by many factors: heavy precipitation, severe winds over water, unusual high tides, tsunamis, or failure of dams, levels, retention ponds, or other structures that contained the water. Periodic floods occur on many rivers, forming a surrounding region known as the flood plain.

Answer 2

Hi =)

The cause of  flood is, too much raining to a part of land. And if the flood happens near of a river, to prevent this a dam can be build. That is a solution to keep cities secure. 

Also if flood happens in city, drains must be open to get rid of water. And sandbags must use to direct water stream around of the living area.

Also planting trees will reduce the effect of flood. They will keep the soil firm and will not let them fall apart.

Good Luck :)