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Office of Emergency Management
Dam and Flood Safety

Flooding is the top hazard in prince William county; Are you ready?


Frequently Asked Questions - flooding

  • What is flooding? Flooding is an overflow of water that covers land that is usually dry. Flooding occurs in flood plains but flooding can happen anywhere with heavy enough rain.
  • Is my property in a floodplain? To see if your property is in a designated Federal Emergency Management Agency (FEMA) floodplain or a Virginia Storm Surge Zone, click here for an interactive lookup tool.
  • What do I do during flooding? Don't walk in flood waters, especially moving water. Never drive in flood waters- Turn Around Don't Drown!®
  • What is the difference between a watch and a warning? A flood watch means that conditions are right for flooding to occur. A flood warning means that flooding is occurring or imminent, be careful! Want to know when a flood watch or warning is in effect? Sign up for free PWC Alerts here.
  • What is a storm surge? Storm Surge is the rise of sea water level due to heavy amounts of rain. Storm surge can cause flooding too!
  • What are the VDEM Evacuation Zones A-D? In other parts of Virginia, the Virginia Department of Emergency Management has established designated evacuation zones, identified as “Zone A – D,” primarily for Hampton Roads, the Northern Neck, and the Eastern Shore. Prince William County still has the potential to experience storm surge along the Potomac River, along with inland fresh water flooding of area waterways.

Be prepared


There are lots of things that you can do to minimize the impact of flooding before it happens. Below are some tips to help you get started.

  • Know your risk. Find out if you live in a dam inundation zone by looking at our interactive tool here.
  • If you live or work in a dam inundation zone find out what your risk is here. This will tell you what is the dam's hazard classification and if it is publically or privately owned.
  • Know what your evacuation zone route will be.
  • Buy flood insurance. Prince William County Residents now receive 15% off their flood insurance premiums because of the CRS. Flood insurance does cover damage from dam flooding, buy now for your peace of mind.
  • Find out the communication method that will be used in the event of a dam breach.
  • Build an emergency kit with your family to take with you if you have to evacuate. Click here for more information on how to build a useful emergency kit.
  • Inform your family of dam failure and flood risks. Make a plan with your family for how you will communicate and find each other in an emergency. Here is a fillable family communication plan.
  • Sign up for free PWC Alerts to get fast information on potential or occurring emergencies. You can sign up for free here.


Flooding is dangerous and it is important to stay safe during flooding events. Here are some ways you can stay safe while navigating flooding emergencies.

  • Listen to PWC Alerts, local TV, or Radio for updates on evolving dam and flooding situations.
  • If you are told to Evacuate:
    • Secure your home
    • Turn off utilities
    • Plan to take your pets with you
    • See if your neighbors need assistance
    • Take your emergency kit with you
    • Don't walk or drive through flood waters


Even after flood waters recede there can still be hazards. Here are some steps you can take to be safe after flooding.

  • Don't go back into flooded areas until you are told that it is safe by public safety officials.
  • Take pictures of your damage.
  • File your flood insurance claim as soon as possible.
  • Try to prevent mold damage on items with floodwater on them. Mold damage is not covered by flood insurance.

may 31st is national dam safety awareness day

The dams in our community are safe and well maintained, but we ask that you take a few moments to review the information below in the event of an emergency at one of our dams.

preparing for a dam emergency


  • Click the map image below to use the interactive tool and see if you live downstream of a dam or in a dam inundation zone.
  • Consider purchasing flood insurance, as most homeowner's and renter's policies do not cover flood damage.
  • Sign up for PWC Alerts at


  • Pay attention to local authorities and if you are told to evacuate, please do so immediately.


  • Do not return to your property until authorities say it is safe.
  • Take pictures of your damaged property.

if you see suspicious activity around a dam, call 911

To find out if your home or business could be impacted by flash flooding from a dam failure, type your address in the interactive lookup tool below.


  • Dam Inundation Zone- a dam inundation zone is the area downstream of a dam that would be flooded if there was a dam failure or an uncontrolled release of water.
  • Dam Failure- Prince William County dams are very safe, and dams failures are low probability events. While infrequent, impacts of a dam failure can be catastrophic. Dam failure is often cause by structural, mechanical or hydraulic failure. Storm events do not usually cause dam failures

For more information about dam safety in Prince William County visit


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