Understanding Floods and Their Causes

What is a flood?

• A sudden heavy rainstorm

• An overflow of water onto dry land

• A type of drought

• A wave from the ocean

How can floods occur?

• Only through heavy rains

• Only when ice melts

• River overflow, tsunamis, and hurricanes

• By planting trees

What was the most destructive river flood in U.S. history?

• The Great Mississippi River Flood

• The Grand Ohio River Flood

• The Colossal Colorado River Flood

• The Great Hudson River Flood

What type of flood occurs gradually over time?

• Flash flood

• Rapid onset flood

• Slow onset flood

• Slow ice melt flood

What happens during a rapid onset flood?

• It happens over weeks

• It usually occurs within a day or two

• It can be predicted days in advance

• It is harmless

How quickly can a flash flood happen?

• In a month

• Over a few days

• In a week

• Within 2 to 6 hours

What can help minimize flood damage?

• Building more dams

• Create more roads

• Build better drainage in roadways

• Planting trees with good root systems