Flash Flood Training at COMET

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Flash Flood Training at COMET

• Flash Flood Hydrology and QPE Workshop (Aug 04,
  Sep 04, Jan 05)
• FFMP
• FFG
• Urbanization and Fire Scars
• Mass Wasting (Landslide)
• Radar QPE
• Flash Flood Modeling
• River Ice Jams
• Dambreak

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Flash Flood Training at COMET

• Flash flood will be part of the Basic Hydrologic
  Sciences (Distance Learning) FY06
• Basic Hydrologic Cycle
• Unit Hydrograph
• Land Use
• Rainfall-Runoff Process
• Hydrologic Models
• River Ice

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Flash Flood Training Definition

• A life threatening flood that occurs within 6
  hours of heavy or excessive rainfall, dam or
  levee failure, or sudden release of water from an
  ice jam
• Note Flash flood is often within 1 hour of
  intense rainfall in river ice situations the
  flood usually occurs upstream of an ice jam

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Flash Floods in Storm Data

• 1. Heavy rain caused street flooding just as
  street festival was underway (street was not
  closed)
• No listed info on timing w.r.t. intense rainfall
• No injuries, no damages reported
• 2. Road closed due to flooding.
• About 2 hours after intense rainfall began
• No injuries or damages listed

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Flash Floods in Storm Data

• 3. Major flooding across the county. (Long
  description described excessive rainfall amounts
  and road closures over four days for multiple
  counties).
• 12 hours or more after rain began, in effect for
  9-17 hours
• 1 fatality, 10K damages
• The same description appeared for more than 12
  counties, some called it flood, some called it
  flash flood.

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Flash Flood Training Issues

• What do you do if you get reports of water on the
  road?
• Depth criteria?
• More than localized?
• Is a road closure report a flash flood for
  certain?
• What about potential levee failures when flood
  warnings are already issued?
• In remote areas, can there be a rainfall
  threshold criteria?
• How do you know when an urban flood (nuisance)
  becomes a life-threatening flash flood?