Flood maps

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Flood maps Modeling a levee break
http//www.msa.saccounty.net/waterresources/stormr
eady/default.asp
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Flooding

• Urban flooding
• Paved areas and storm sewers increase runoff by
  inhibiting infiltration
• Rapid delivery of water to streams increases peak
  discharge and hastens occurrence of flood
• Flash floods
• Local, sudden floods of large volume and short
  duration
• Typically triggered by heavy thunderstorms

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Flooding

• Flood control
• Dams designed to trap flood waters in reservoirs
  upstream and release it gradually over time
• Artificial levees designed to increase capacity
  of river channel
• Works well until stream overtops artificially
  raised levees, leading to extremely rapid
  flooding and erosion
• Wise land-use planning, including prevention of
  building within 100-year floodplains, is most
  effective

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Real-time river data
http//cdec.water.ca.gov/river/rivcond.html htt
p//cdec.water.ca.gov/river/americanStages.html