LaSalle County Flood Hazard Information


Effective Map Products

Effective Flood Insurance Rate Maps for LaSalle County may be viewed and/or downloaded at the FEMA Flood Map Service Center (MSC)

NFHL Viewer (more detailed flood data displays when zoomed in). It may also be slow.

Launch full screen NFHL Viewer


  • Inundation Map of the Illinois River at Ottawa, IL
  • Lower Fox Watershed Discovery

  • Additional Resources

  • Unmapped Special Flood Hazard Areas (SFHA) (pdf)
  • Destined for DFIRMs - stream studies becoming flood maps
  • Building Footprints
  • Topographic Wetness Index
  • Links to National Flood Insurance Program (NFIP) Information