Flash Flood: What is it?


5 min read ยท Mar 20, 2022

If you’re lucky, you’ll only experience flash flooding as part of a fantastic movie. The last thing you’d want to see coming at you is a solid wall of water carrying uprooted foliage and anything else that gets swept up in the torrent. Flash flooding occurs in all fifty states and beyond and can cause catastrophic loss and devastation if you’re caught unprepared to handle such an event.

What is a Flash Flood?

According to the National Weather Service, a flash flood is “flooding that begins within 3 hours of heavy rainfall”. Flash flooding can also occur due to levee and dam failure and debris flow which is a side effect of heavy rain.

Factors that Affect Flash Flooding

Several factors can affect flash flooding conditions. Some of these conditions include:

1. Heavy Rain and Impenetrable Soil

Continued heavy rains on soil that is unable to absorb more water result in a deadly combination of flowing water that must go somewhere. Flash flooding is prevalent in desert regions after compacted soil is unable to handle the onslaught of water in a very short time.

2. Mountain Thaw and Rains

As spring arrives, ice and snow from higher elevations will naturally trickle down to low-lying areas. The combination of naturally flowing streams and heavy thunderstorms can produce catastrophic flooding conditions that take place in mere minutes.

3. Tropic Storms Such as Hurricanes and Typhoons

While most people assume that the high winds and flying debris characteristic of hurricanes do the most damage to homes and property, it’s water that can cause the most damage over time. Many tropical storms cause both slowly rising floodwaters and flash flooding in areas where capacity is too great for land to bear.

4. Dams and Levees

When the Banqiao Reservoir Dam gave way in China following Typhoon Nina, at least 171,000 people perished in the flash floods that occurred. As a result of the dam failure, 11 million survivors were left completely homeless, their homes and property destroyed by the catastrophic effects of rapidly rising water. Manmade dams and levees are effective at holding backwater, but they do give way under certain conditions. Additional stress placed on them by Mother Nature often results in dangerous conditions that give you only minutes to react as you rush to safety.

The intensity of rainfall, land use and topography, and soil saturation are all factors that affect an area and its predisposition to flooding. The danger of flash flooding is that it can occur so quickly that people are caught off-guard. Attempts to escape a flooded area or to take time packing items needed for survival can place you and your family in grave danger if you don’t take precautions ahead of time. Particularly if you live in an area prone to flash flood warning, you need to be prepared to handle what the next storm sends your way. Take these steps to ensure that you reach higher ground safe and sound:

Avoid Building in Flood-Prone Areas

If you have a choice, consider building or residing in areas that are not prone to flooding. Know your risk and take precautions to prepare you and your family if flooding does occur. Consider purchasing flood insurance to protect you and your loved ones from loss or harm.

Have Preparation and Evacuation Plans

Once you know your risks, make plans for preparing your home and your family for shelter-in-place and evacuation, if necessary. Establish evacuation routes, pack survival gear, and communicate these plans to your friends and family to ensure that you can act without delay in the event of an emergency. Establish clear protocols for communication with each other so that if you become separated, you can all move toward your chosen safe space and reunite as quickly as possible. Listen to local weather outlets and channels to stay informed about changing conditions in your area, and act proactively rather than reactively to make sure you can get to safety before conditions become too dangerous to leave.

Pack Emergency Supplies Ahead of Time

If you live in an area prone to flooding, you need to have emergency supplies already packed. These bags should be ready to go at a moment’s notice and should be regularly monitored and updated to ensure that you don’t forget much-needed supplies. Add these items to your “go bag” to stay as comfortable as possible in your emergency holding space:

  • Non-perishable food (enough for 3-5 days)
  • Bottled water (enough for 3-5 days)
  • First aid kit
  • Pet carriers and pet supplies needed for care
  • Clothing
  • Personal care items
  • Cell phones and charging cords
  • Electronics, laptop or tablet
  • Blankets, pillows
  • Medications needed for family members
  • Books, magazines, games for children

Not all these items are essential; determine what is most needed and start with that, then add what you can carry to a new destination without compromising your own security and safety.

Prep Your Home for Flooding

If you can’t avoid building or living in a flood plain, do what you can to flood-proof your home. Move all electrical appliances and wiring above historic flood lines, elevate furniture and fixtures that you would like saved in the event of a flood, and keep valuables and other precious items on an upper level of your home to reduce loss and damage to your belongings. Pack up lawn furniture and secure outside items and equipment inside a secure shed, and turn off all utilities such as water, gas, and electricity before evacuating your home. The more efficiently you can prepare your home ahead of time, the more likely it is that you’ll be able to salvage some of your belongings when it is safe to return to your property once more.

Preparation is Key to Minimizing Damage and Loss

Knowing how to stay informed in the event of a flood, as well as what steps to take to prepare you and your loved ones, will be an essential part of minimizing damage and loss. One of the most important things you can do to protect yourself and your family is to invest in flood insurance. At Neptune Flood, we specialize in plans that cover you in times when you need it most. Cutting-edge algorithms and affordable pricing plans ensure that you get personalized coverage plans that work for you, your home, your budget. Contact us today to see how we can provide you with more peace of mind this storm season. Visit our website, NeptuneFlood.com, for more information.

Original article published May 2018. Updated content and references March 2022.