Todays topic during this flood safety and wildfire awareness week is flash floods.
Flash floods are no strangers to Colorado. Close to 300 people have been killed in flash floods across the centennial state since the year 1900.
The worst flash flood occurred on July 31 1976 in the big Thompson canyon between Estes Park and Loveland. A nearly stationary storm produced around 12 inches of rain in 4 hours…claiming 144 lives.
Two other notable flash floods in Colorado were…
The 1904 incident…just north of Pueblo that drowned just over 100 people as a bridge failed…plunged a train into fountain creek.
The 1997 Fort Collins episode killed 5 people and caused $200 million in property damage.
A flash flood is defined as a rapid rise in water levels…generally occurring in less than 6 hours…along large creeks…normally dry washes…arroyos…or over normally dry land area…and can occur with little advanced notice.
Flash floods frequently result from high rainfall rates…and infrequently from dam failures…levee failures…or sudden breaks in river ice jams. Flash floods are very destructive…due to the force of the moving water...and the accompanying debris. This tremendous force can easily damage or destroy roadways...bridges…and buildings.
In recent years…Colorado has seen major flooding and damage when heavy rains have occurred on wildfire burn scar areas. If you are in or near a burn scar area…you need to plan ahead. Be aware of general flash flood plans and procedures that have been developed and implemented by your local emergency management officials. It’s up to you. You should know your flash flood risks…and make your plan to save your life and those around you.
The National Weather Service forecast offices will discuss flash flood potential in daily hazardous weather outlooks…and in graphical weather stories on national weather service forecast office web sites.
During days when flash flooding is possible a flash flood watch will be issued.
During days when flash flooding is likely or occurring a flash flood warning will be issued.
When a flash flood warning is issued for your area...you need to act quickly if you are in a drainage area or in other low spots. Know your escape routes to higher ground and act as quickly as possible. It may be just a short walk or climb to that higher ground.
Many flash flood deaths occur in vehicles. Do not drive through a flooded roadway. The water may be much deeper than you think…because the roadway may be damaged or washed away. One to two feet of water will carry away most vehicles. Instead turn around...don’t drown.
Flood safety and wildfire awareness week continues through this Saturday.