100 Year Floor Zone

Zone x shaded is used on new and revised maps in place of zone b c x unshaded minimal risk areas outside the 1 percent and 2 percent annual chance floodplains.

100 year floor zone.

The primary risk classifications used are the 1 percent annual chance flood event the 0 2 percent annual chance flood event and areas of minimal flood risk. Sfhas are labeled as zone a zone ao zone ah zones a1 a30 zone ae zone a99 zone ar zone ar ae zone ar ao zone ar a1 a30 zone ar a zone v zone ve and zones v1 v30. A 100 year flood is a flood event that has a 1 in 100 chance 1 probability of being equaled or exceeded in any given year. I use the term 100 year flood zone daily for elevation certificates loma s and explaining flood maps.

The 100 year flood is also referred to as the 1 flood since its annual exceedance probability is 1. The term 100 year flood is used to describe the recurrence interval of floods. But it doesn t mean what you might think. In other words the chances that a river will flow as high as the 100 year flood stage this year is 1 in 100.

It means there is a 1 chance you will see a flood like the one on the fema flood map each and every year. The 100 year flood is referred to as the 1 annual exceedance probability flood since it is a flood that has a 1 chance of being equaled or exceeded in any single year. This zone is also used to designate base floodplains of lesser hazards such as areas protected by levees from 100 year flood or shallow flooding areas with average depths of less than one foot or drainage areas less than 1 square mile. The 100 year recurrence interval means that a flood of that magnitude has a one percent chance of occurring in any given year.

Flood zones are indicated in a community s flood map. C and x unshaded 500 year floodplain. No bfes or base flood depths are shown within these zones. The 1 percent annual chance flood is also referred to as the base flood or 100 year flood.

Everyone lives in an area with some flood risk it s just a question of whether you live in a high risk low risk or moderate risk flood area. Fema maintains and updates data through flood maps and risk assessments. Flood mapping is an important part of the national flood insurance program nfip as it is the basis of the nfip regulations and flood insurance requirements. No bfes or base flood depths are shown within these zones.