Federal Emergency Management Agency (FEMA)

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Federal Emergency Management Agency (FEMA)

• Flood Map Modernization Project

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Map Modernization

• What is Map Modernization?
• Digital FIRM vs. Current Effective Paper Map
• Base Map
• Topography
• Flood Data
• Input from the Community for DFIRM Production

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What is the FEMA Flood Map Modernization Program?

• Map Modernization transforms the Nation's flood
  maps into more reliable, easier-to-use, and
  readily available digital maps.
• FEMA Map Mod is a 750 Million program to
  provide reliable flood maps and data to support
  the National Flood Insurance Program (NFIP). No
  cost to you, the community
• FEMA has developed a 5-year plan for providing
  updated digital flood hazard data and maps for
  areas with flood risk. The completion of flood
  map updates initiated in the plan extends to
  2010.

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Why Modernize?

• Many existing flood maps may not reflect current
  conditions or natural changes in the environment.
• Most existing flood maps are more than 10 years
  old.
• Flood hazard conditions are ever-changing.
• New maps can take advantage of revised data and
  improved technologies for identifying flood
  hazards.
• More timely updates of floodplain maps and easier
  access to the data

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Digital FIRM

Base Map
Digital FIRM

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Base Map

Ortho Base Map
Vector Base Map
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Base Map

• Identify Existing Available Data
• Aerial Photography
• Planimetrics / Roadway
• Hydrography
• Political Boundaries
• Bench Mark Data

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Topography

• Topography Data Sources
• USGS 30 meter DEMs(digital elevation models)
• USGS 7.5 min quadrangles (elevation contours)
• Local / Countywide Topographic Data
• LiDAR (Regional or Statewide)

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Flood DataStudy Methodologies

• The following types of study are available
• Digital conversion digitizing current effective
  flood boundaries/floodway with best available
  topographic enforcement
• Re-delineation re-delineating the effective
  models onto new topography (no new modeling)
• Approximate Study (Zone A)
• Detailed Study (Zone AE)

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Approximate Study

• Replaces Unnumbered A Zones
• Automated approach
• Hydrology from Regression Equations
• Hydraulic model developed
• No hydraulic structures
• No calibration
• Flood boundary mapped from model
• No cross section, BFEs, or floodways shown on
  map
• Considered an A Zone
• Base model for future refinement

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Detail Study

• Traditional Detail Study
• Sections Field Surveyed
• Detailed Hydrologic Analysis
• Detailed Hydraulic Model
• Hydraulic Structures Surveyed
• Model calibrated
• Traditional Mapping
• Floodways
• Floodway Data Table
• Flood Profiles

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What Do We Need From You?

• Information requested from local community
  regarding proposed study
• Digital Base Data
• Recent topographic data or survey
• Any new or existing flood studies
• Flooding or flood improvement project information
• Identification of areas that flood but are not on
  current FIRMs as flood zones
• Identification of areas that do not flood but are
  on current FIRMs as flood zones

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What Do We Need From You?(cont.)

• Information requested from local community
  regarding proposed study
• Identification of areas where new or planned
  development may impact flooding
• Future land use plans
• Copies of floodplain ordinances
• Other information

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Key Objectives to Complete during Scoping Meeting

• Mark up scoping map / FIRM panels
• Identify needs and provide rationale for each
  reach proposed for study
• Discuss your communitys priorities
• Decide on priorities for whole group / area
• Identify points of contact for participants