100-Year Floodplain: How Can I Use It to Keep Me Safe from Floods?

100-Year Floodplain: How Can I Use It to Keep Me Safe from Floods?

What is “100-year floodplain”?

Have you ever heard of 100-year floodplain ? If you live in a coastal area, or in a region that has a history of flooding, you have probably come across the term. The expression “100 year flood” can be a little confusing, as it makes it seem like it only happens every 100 years, but it’s not quite that.

In fact the number refers to a statistical probability. He describes that a flood has a 1% chance of hitting a certain area in any given year. An area with a one percent chance of flooding is in the 100-year floodplain.

100 year floodplain , entered American vocabulary in 1973, stating that if a piece of land fell within the limits of where a flood has a 1% per year chance of happening, new construction should be raised and insured.

A line had to be drawn somewhere to make the FEMA flood maps. A 1% annual risk of flooding was the line drawn by FEMA. Being in or out of the 100-year flood zone is just the requirement for purchasing mandatory flood insurance. It’s a minimum standard and doesn’t mean your home won’t flood if you’re outside the zone.

Flood Zones 101 – understand how it works

It’s important to keep in mind that while the 100-year flood is a statistical expectation, floods can happen more or less frequently. They can also be more severe than anticipated, with the amount of water much higher than expected.

Where can I find information about “100-year floodplain”?

NFIP flood maps identify 100-year-old floodplains across the United States and group them into Flood Zones based on their risk.

In addition to the floodplain boundaries, the flood maps show any base flood elevation or flood depths for the area. The following flood zones are in a 100-year floodplain:

Flood Zone A

Flood Zone AE

Flood Zone A1-30

Flood Zone AH

Flood Zone AO

Flood Zone AR

Flood Zone A99

Flood Zone V

Flood Zone VE, V1-30

As these zones are on a 100-year floodplain, they are labeled Special Flood Hazard Areas . Which makes Flood Insurance mandatory for anyone with a federally backed mortgage.

If we use these same statistics, over the course of a 30-year mortgage, so that you better understand how forecasts are defined, we can put it this way:

  • The 25-year-old Flood Zone offers a 71% chance of being flooded
  • The 50 year old Flood Zone offers a 45% chance of being flooded
  • The 100-year-old Flood Zone offers a 26% chance of being flooded
  • The 500 year old Flood Zone offers a 6% chance of being flooded

When you look at the 100-year flood zone this way, you have a 1 in 4 chance of experiencing flood damage during your 30-year mortgage. And even if it is outside this zone, which is still a “line” on the map, the insurance obligation disappears, but does the risk of suffering from floods also disappear?

You can search your property’s flood zone at the Federal Emergency Management Agency’s Flood Map Service Center.

What is Base Flood Elevation?

Base Flood Elevation (BFE) is the height that the water surface is expected to reach during a 100-year flood. The NFIP and private insurers use BFEs to determine the value of their Flood Insurance, and contractors should also consider BFEs when designing and building homes in Flood Zones.

My property is in a 100-year flood risk area, now what?

Well, if you bought the property via financing, then probably flood insurance was already required, right? Federally regulated and supported mortgage lenders can only lend money to homeowners in a risk zone if insurance is guaranteed.

Even private creditors make this requirement. The lender makes sure that the property used as collateral on the loan will be safe if the statistics are right, why wouldn’t you want to when that property is your home?

A 100-year-old flood doesn’t always happen, but if it does, it could be a catastrophe. And not the only type of flooding you have to worry about. Minor floods can cause as much damage as any other.

Other floods may not be as severe, but they occur more often, especially if you are in an area with low elevation or close to water. For you to have an idea being close to water, your home runs the following risks:

  • 45 percent change to see a 50-year flood.
  • 71 percent chance of seeing a 25-year flood.
  • 96 percent chance of seeing a 10-year flood.

If you consider that the risk of your house burning down in a mortgage period is 1%, you can understand the size of the risk of being hit by a flood, right?

How to protect my property in a 100 years floodplain?

The first step I’m sure you already know: get a Flood Insurance, urgently! If your home is in an NFIP-eligible area, your policy will likely look like this:

  • Waiting period of 30 days before the start of coverage, that is, there is no point in hiring when it starts to rain.
  • $250,000 limited to dwelling coverage of your home.
  • $100,000 cap on your personal property coverage.

You can also take out your insurance with private insurers and adjust the limits and coverage to your needs.


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