Disaster Recipes: Floods 101

Wildfires are caused by the combination of heat, oxygen, and fuel — we human beings are the most common cause of wildfires. Hurricanes are the result of ocean warming that results in evaporation of water into the air, which in turn can morph into a powerful storm that will carry water over land. Floods are the result of the high concentration of water that's being carried in the air by a storm, and it getting dumped over land all at once.

"Floods are among Earth's most common–and most destructive–natural hazards." —NatGeo

Ingredients

To create a flood, you'll need one of a few things to happen, that might be interrelated:

• A lot of prolonged rain (or rapidly melting snow)
• A major storm, like a tropical cyclone
• A failing dam or levee

Depending upon which ingredient being the main root cause of a flood, it'll be categorized into one of the two types of floods:

1. Flash flood
2. Storm flood

A flash flood can be either be the result of a failing dam or levee (i.e. where the capacity of the dam or levee exceeds its physical limitations), or it can be the result of unexpectedly high rainfall (or rapidly melting snow). Keep in mind that urban areas are more susceptible to flash floods because concrete and asphalt surfaces to do not absorb water like natural ones — and thus they divert water to drainage systems with extreme intensity when rain is intense.

A storm flood is the result of the progression that we know can make a little storm grow all the way into a tropical cyclone, or "hurricane," which enables the wind to carry large amounts of water from the ocean — dumping that water on land. As you can imagine, a storm flood can also lead to flash floods occurring after the storm may have subsided. A flash flood, by definition, happens "all of a sudden" and is much more difficult to predict than a storm flood, which is something you can see coming.

"Just six inches of moving water can knock you down, and one foot of moving water can sweep your vehicle away." —Ready.gov

Steps

1. Draw water out of the ocean into the air.
2. Dump that water on land over a period of time.
3. In some cases, dump it in areas where there is a dam or levee holding water.

There's a domino effect to consider when a hurricane happens — because flooding is a likely outcome. Other dominos to fall include power outages, building damage, landslides, and transportation disruption.

Luck always favors the prepared, so be sure to have a plan in place for if a flood were to happen to properly protect yourself and your family. Don't forget to include your pets. And keep important documents in waterproof containers whenever possible.

How To Stay Safer During A Flood

TURN AROUND, DON'T DROWN! —Ready.gov

• Seek shelter immediately. Monitor weather conditions.
• Do not try to go through a flood. "Turn around, don't drown!"
• Avoid going over bridges that span fast-moving waters
• Listen to authorities to know if: 1/ you should stay in place, 2/ you should evacuate, or 3/ you should seek higher ground
• If you are in a car and water's entering it, get on top of the car; if you are in a building and water's entering it, get to a higher floor

How To Stay Safer After A Flood

• Only return to the flooded area when authorities give a green light
• Wear thick gloves and protective gear to be safe
• Electrocution is likely when standing in water — be careful
• Snakes and other animals may have entered the flooded area
• If using a generator, be sure that there's adequate ventilation

What's The Difference Between a Dam and a Levee?

• A dam separates two bodies of water and raises the level of water on one side of the dam. In doing so, this difference in height enables powering an electrical generator.
• A levee is an earthen barrier that separates land and water as a means to deter a flood from happening.
• A dike is a kind of levee that keeps land that would usually be underwater, instead usable and dry. In other words its pushing back against nature, consciously.

Interestingly, a levee that's made of concrete is more commonly called a "floodwall" — isn't that a great term? It makes a ton of sense.

Resources From Everbridge Experts

At Everbridge, we keep people safe and organizations running. Faster.

• Back in 2010, Everbridge became known as a critical technology in New England
• In 2013, we went all-in on integrating the weather into everything that we do
• Use Everbridge's tip sheet for managing communications during severe weather

Related Content

Disaster Recipes: Hurricane 101 is now available .

Disaster Recipes: Wildfire 101 is now available .

References

• Flood myths by Dr. Samantha Montano
• USGS Water Dashboard
• Hurricane Henri 8/2021
• NDA.org: Flooding
• Ready.gov: Floods
• WilcoMarsh Buggies
• Kids Brittanica
• FEMA Flood 1-Pager
• PRB.org Types of Disasters
• Twitter: Major Rain Example