Flood Facts


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Did You Know?

  • Other than fire, floods are the most common and widespread of all natural disasters.
  • 90% of all presidentially-declared U.S. natural disasters involve flooding.
  • Floods occur within all 50 states (they can occur anytime, anywhere).
  • 25% of flooding occurs outside areas formally designated as flood prone (i.e. Special Flood Hazard Areas).
  • Nationwide, flooding caused more than $4 billion a year in losses and 2,200 deaths in the 1990's.
  • There is a 26% chance of experiencing a flood during the life of a 30-year mortgage (more than six times the likelihood of a fire).
  • Even minor flooding can cost thousands of dollars in losses and repairs.
  • Flood damage is virtually never covered by standard insurance.
  • Flood insurance purchased through the National Flood Insurance Program (NFIP) is relatively inexpensive.
  • Today NFIP insures more than four million policyholders in more than 19,000 communities in the U.S.
  • Florida residents and businesses hold more than 40% of all flood insurance policies in the nation.
  • Palm Beach County has many programs to mitigate flood risks and assist residents before, during and after flood events.
  • As a relatively flat, low lying, heavily developed coastal county that experiences frequent intense rain events and periodic tropical storms, Palm Beach County is especially susceptible to flooding.

Some causes of flooding:

Storm Surge
Storm surge is a large dome of water, often 50 or more miles wide, which sweeps across the coastline near where a hurricane makes landfall. Storm surge is the greatest threat to property and life along the affected coast.
Flash Flooding
Intense rainfall in a brief period leaves more water than the ground can absorb. When this happens, flash flooding can occur. Flash floods occur with little or no warning, move at very fast speeds and can reach a peak in a few minutes. They can roll rocks and boulders, tear out trees and destroy buildings and bridges.
Nature isn't the only cause of flooding
New construction and paving alter land's ability to drain properly. As a result, run-off can increase two to six times over what would occur on natural terrain. Areas that were initially zoned as low-risk can quickly become high-risk as urban development alters topography.
Primary causes of flooding in Palm Beach County
Several factors contribute to Palm Beach County's flooding. Among these are rainfall intensity, rainfall duration, surface conditions, topography, and poor natural drainage. An increasingly significant contributing factor is rapid water runoff associated with the vast areas of impervious surfaces created by new development, often creating flood prone areas where they didn't previously exist.
Flooding often occurs as a result of extended wet periods that create saturated soil conditions, after which additional rain causes surface ponding or overflows catchment canals and ponds.
Intense or prolonged concentrated rain is the primary cause of localized flooding throughout the county.
Maintenance of major drainage canals and pumps is critical to managing the area's water levels, as is keeping neighborhood drainage systems free from obstructions. The task of managing water levels is slowed and complicated by our flat terrain.
Palm Beach County's coastal areas are susceptible to storm-surge flooding--the sudden and massive build up of water levels by the force of onshore winds produced by tropical storms, hurricanes, and northeasterners. Water levels of 12 feet or more can overflow normally dry lands with devastating results. The severity of flooding can vary significantly based on a variety of factors such as storm intensity, forward speed, angle of attack, the slope of continental shelf, tidal conditions, etc. The northern and southern coastal areas of the county are somewhat more susceptible to surge flooding than are the central sections.
Improbable, but very serious flood threats include the potential overtopping of Lake Okeechobee or a breach of the Herbert Hoover Dike that helps contain the Lake. An event like the 1928 hurricane flooding which killed thousands in western Palm Beach County remains a worst-case flood disaster scenario.
Do you need insurance?
As we have stated earlier, flooding can occur anywhere, anytime. Even if you are not required to have flood insurance, serious consideration should be given to purchasing it anyway.
Business insurance may cover fire and wind damage, but virtually never covers damage from flooding...nature's most common natural disaster. Damages associated with floods can easily total $25,000 or more.... sometimes much more.
Because Palm Beach County participates in the National Flood Insurance Program, all county businesses qualify to apply for NFIP flood insurance.
Without flood insurance, losses must be covered out of pocket. Some limited relief might be obtainable through government aid. But, government assistance is not available automatically. It is offered only when the President makes an official disaster declaration. Less than half of flooding events are "declared disasters." Declarations require rather widespread damage. Most often, when government aid is available, it comes in the form of an interest bearing loan.
What does flood insurance cover?
Under the National Flood Insurance Program (NFIP) a flood is defined as a general and temporary condition of partial or complete inundation of normally dry land by:
  • The overflow of inland or tidal waters.
  • The unusual and rapid accumulation or runoff of surface waters from any source.
  • Mudslides (i.e., mudflows) which are proximately caused by flooding as defined above and are akin to a river of liquid and flowing mud on the surfaces of normally dry land areas, including your premises, as when earth is carried by a current of water and deposited along the path of the current.
  • The collapse or subsidence of land along the shore of a lake or other body of water as a result of erosion or undermining caused by waves or currents of water exceeding the cyclical levels which result in flood as defined above.
To qualify as a general and temporary condition, the flood must affect either two or more adjacent properties or two or more acres of land and have a distinct beginning point and ending point. Also, to qualify, the flood waters can only be surface water that covers land that is normally dry.
Flood insurance is mandatory if:
  • your property resides in a Special Flood Hazard area
  • you have a federally backed mortgage on a business in a high risk area
  • you have received a federal grant for previous flood losses and you wish to qualify for future aid
  • find out if your property resides in a Special Flood Hazard Area
A flood policy can cover:
  • flood debris cleanup
  • structural damage (walls, ceilings, floors, stairways, etc.)
  • equipment/utilities damaged by floodwater
  • wall-to-wall carpeting, tile and other flooring surfaces
Contents coverage can cover:
  • furniture
  • office equipment
  • artwork, decorations
  • other contents as defined in your policy

The maximum coverage limits under a standard business flood policy are $500,000 for a structure and $500,000 for contents. The coverage limit for renter contents is $500,000.

Business owners in lower risk areas may qualify for a "preferred risk" policy which provides the same coverages at substantially lower rates.

For More Information on Flood Insurance

Your insurance agent most likely can provide you with all the information you need and answer any questions you have. If not, additional information can be obtained directly from the National Flood Insurance Program by calling 1-888-CALL-FLOOD. You can access the NFIP website at www.fema.gov/nfip

Flood Warning System

Palm Beach County depends on the National Weather Service (NWS) for flood recognition. The NWS will issue a flood advisory for Palm Beach County at least 6 hours before expected rainfall would overflow drainage systems and cause the isolation of structures by the inland ponding of flood waters.

Businesses should stay tuned to local TV or radio stations known to have an active news bureau or to a NOAA weather radio for information. When flood warnings are issued, it will be done first through the Emergency Alert System then, via the mass notification system (AlertPBC), the PBCDART App (search

PBCDART on App Store or Google Play), then if needed, by sirens and loudspeakers from police and fire vehicles who will give evacuation orders.

Evacuation routes will be announced at the time the evacuation order is given. Main routes will include US Highway 1, I-95, the Turnpike, and all east-west arterials.