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King County Office of Emergency Management
3511 NE 2nd Street
Renton, WA 98056
Main Phone: 206-296-3830
Toll Free: 800-523-5044
Fax: 206-205-4056
ecc.kc@kingcounty.gov

Enhanced 911 Program
Seattle, WA
206-296-3910

Dam FailuresImage: Dam

There are 87 dams in King County that impact 10 acre-feet or more of water. The Washington State Department of Ecology classified eight of these dams as having a high downstream hazard potential (defined as a population at risk of more than 300). Conversely, 48 of these have a low hazard potential (population at risk of zero).

King County has four major dams that would cause a countywide emergency if they should fail. These dams are located on the Tolt, Cedar, White, and Green rivers. Certain areas of King County would also be adversely affected by failures of the White River Project located in Pierce County or the Jackson Project located in Snohomish County. Additionally, localized problems could occur if one of the minor dams in the county failed.

The chief concern of a major dam failure in King County would be the resulting flooding hazard to area residents. As a result, it is important to be prepared for this risk by creating a plan and building a disaster kit in case flooding from a failed dam impacts your home, business, school, or commute.

Howard Hanson Dam - Green River Basin flood plan

Image: Steps Hazard-specific Preparedness Steps

  1. Learn the safest route from your home or business to high ground.
  2. Make arrangements for housing in the event you need to evacuate your home.
  3. Teach all family members how, where and when to turn off utilities.
  4. Plan for a meeting place outside of the hazard area.
  5. Learn how to prepare for flooding which typically accompanies dam failures.
  6. See General Preparedness Steps below for more disaster planning basics.

Image: Steps Response Steps

  1. Listen to your weather radio, regular radio or television for emergency information. 
  2. If told to evacuate, do so as soon as possible. Delay or refusal to evacuate can jeopardize your safety, the safety of emergency responders, and hinder rescue efforts.
  3. Move your furniture and valuables to higher levels in your home if you have time.
  4. Move to higher ground away from rivers, streams, creeks and storm drains.
  5. Do not drive around barricades; they are there for your safety.
  6. Never drive through a flooded area. Cars can be carried away by just two feet (2') of water.
  7. Don't walk or wade through flood waters. You can be knocked off your feet by as little as six inches (6") of moving water.

 Image: Steps General Preparedness Steps

  1. Have and practice a family disaster plan.
  2. Establish meeting places and phone numbers in case family members are separated.
  3. Identify an out-of-state contact to call during a major disaster or emergency; it will be easier to call out of the area if local lines are tied up.
  4. Make sure everyone knows when and how to call 9-1-1.
  5. Keep your disaster supply kits up to date. Make sure you have kits for your home, vehicle, work and school.
  6. Get a tone-alert NOAA Weather Radio to receive emergency notifications and up-to-date information and instructions.
  7. Teach all family members when, where and how to turn off utilities. Make sure you have the appropriate equipment, such as a wrench, handy.
  8. Make sure you understand the emergency plans and expectations at your child's school and your work.
  9. Preplan alternate transportation routes to and from work and other important destinations.
  10. Be sure to keep at least a half-tank of gas in your vehicle at all times; power outages often accompany disasters and gas stations rely on electricity to power their pumps.
  11. Know ahead of time what you should do to help family, friends or neighbors who are elderly or have special needs.

See the following "related links" for more details on how to prepare for, respond to, and recover from this type of a disaster or emergency.

Related Internal Links

Related External Links