GIS for Faster Analysis of Dam-Break Flows

1
GIS for Faster Analysis of
Dam-Break Flows

• Steve Pitman
• GIS in Water Resources Fall 2003
• Dr. David Maidment UT Austin

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The Problem

• A breached dam releases large volumes of water
  very rapidly
• Cant predict dam-break floods using observations
  of natural floods
• Existing dam-break models
• Complex, tricky and time consuming
• Not conducive to rapid analysis

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Dams in the U.S.

• Approx. 77,000 total
• Consider a worst case scenario

• On the Colorado River, Glen Canyon Dam
  and Hoover Dam, 370 miles apart, created Lake
  Powell and Lake Mead with combined storage equal
  to roughly four times the rivers annual flow.

USBR Photo
What would this water do if rapidly released?
Lake Powell
USBR Photo
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Teton Dam, Idaho June 5, 1976
Teton Dam, Idaho present day
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GIS in Dam-Break Analysis Today

• Pacific Disaster Center uses the M2M
  interface to translates FLDWAV output
  for display in ArcGIS
• NWS developing
  FLDWAV-GIS link for
  displaying flood predictions
• PBSJ (FEMA Contractor) has fielded a Watershed
  Analyst extension that automates pre- and
  post-processing of watershed modeling data

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Current Dam-Break Models

• DWOPER DAMBRK developed by National
  Weather Service (NWS) in 1970s
• NWS released FLDWAV in 1990s
• Combined DWOPER DAMBRK
• Added functionality

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Adding Automation with GIS
Interface Data Model
Pre-Processing
Post-Processing
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Example
USGS The National Map
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Resources

• Applied Hydrology, Chow et al, McGraw Hill (1988)
• U.S. Geological Survey websites
• U.S. Bureau of Reclamation websites
• National Inventory of Dams, U.S. Army Corps of
  Engineers
• Arc Hydro, Maidment, ESRI Press (2002)
• Source of photos