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FEMA MAP MODERNIZATION in the U. S. Virgin Islands Community Mitigation Branch FEMA Region II June 22, 2006 FEMA MAP MODERNIZATION
WHAT?
WHY?
WHO?
WHEN?
WHERE?
HOW? Flood Map Modernization
Seeks to ensure accurate depiction of flood hazards in areas of high risk
U.S. Virgin Islands is an area of high flood exposure:
2,202 policies in force in U.S. Virgin Islands ($308 Million in coverage)
$1.6 Million in annual premium payments
1,552 closed paid losses in U.S. Virgin Islands ($39 Million in payments)
Subject to storm surge flooding from Tropical Cyclones
Subject to hydrologic flooding associated with Tropical Cyclones and severe storms What is the FEMA Flood Map Modernization Program?
FEMA Map Mod is a $750 Million + program to provide reliable flood maps and data to support the National Flood Insurance Program (NFIP)
Over 20,000 communities nationwide participate in the NFIP.
The Multi-Year Flood Hazard Identification Plan (MHIP) details FEMA’s 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.
Map Mod transforms the Nation's flood maps into more reliable, easier-to- use, and readily available digital maps. Multi-Year Flood Map Modernization Plan (MHIP)
Details FEMA’s 5-year plan for providing updated digital flood hazard data and maps for areas with flood risk
The updated digital maps are easier to use and maintain than the existing maps, which are mostly paper.
They are also easier and less expensive to update.
The completion of flood map updates initiated in the plan extends to 2010. Why Modernize?
Flood hazard conditions are ever-changing.
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.
New maps can take advantage of revised data and improved technologies for identifying flood hazards.
Up-to-date maps more closely identify actual risk.
Local communities and various stakeholders desire more timely updates of floodplain maps and easier access to the data DFIRMs are a significant improvement over current FIRMs Old FIRM New DFIRM Who will make it happen?
Map Modernization is a collaborative effort that cuts across all levels of government and includes other organizations.
Data is shared with other Federal agencies.
The FEMA-contracted National Service Provider, known as the Mapping On Demand Team, will improve consistency throughout the Nation and streamline the goals of Map Modernization through innovation and partnerships.
Michael Baker Engineering is currently the National Service Provider.
The Cooperating Technical Partners (CTP) Program is a collaboration among qualified NFIP communities, state and regional agencies to maintain up-to-date flood maps and other flood hazard information. When ?
The Map Modernization project began in Fiscal Year 2004.
Map Mod is a 5 year plan and is scheduled to be completed in Fiscal Year 2010.
The Map Mod Adoption Process consists of:
Presentation of preliminary maps to a community
2 Public Notices in community papers
Appeal/Protest period
Resolution of appeals
Letter of Final Determination
Map Adoption
Effective Date Map Modernization in the USVI
The end product of Map Modernization is the production of digital flood maps (DFIRMs) that incorporate the latest advanced technologies and the best available data.
The DFIRM production process consists of:
New storm surge and coastal analysis.
Redeliniation of all detailed riverine flood analysis.
GIS format with DFIRM database.
Orthophoto base combining floodway and floodplain data on one map. GIS Format Components of a DFIRM in GIS Format:
Base map
Topographic data
Flood hazard theme
Metadata
Flood Insurance Study (FIS) report
Back-up data (models, etc.) Aerial Imagery Elevation Geodetic Control Boundaries Surface Waters Transportation Land Ownership Special Flood Hazard Areas Coastal Restudy Scope of Work
Coastal Restudy Summary:
The current Effective study did not evaluate hazard risk from waves in detail
There is a significant increase of coastal 1% annual chance water surface elevations
V Zones are now delineated throughout all three islands Components of the Coastal Restudy
New Stillwater Elevations (SWEL)
Derived from the USACE’s state-of-the-art ADCIRC (Advanced CIRCulation Storm Surge Model) and EST (Empirical Simulation Technique).
ADCIRC is a GIS based model.
Storm surge elevations modeled for actual and historical storms such as:
Donna (1960)
Hugo (1989)
Lenny (1999)
EST used to derive 100 year (and other return periods) storm surge elevations from the modeled ADCIRC results.
Wave Setup (piling up of water) added to Stillwater Elevations.
Offshore reef systems taken into account Components of the Coastal Restudy (Continued)
Updated Erosion Analysis
Storm-induced erosion only.
Updated Inland Wave Propagation Analysis
Wave heights determined using the WHAFIS 3.0 (Wave Height Analysis for Flood Insurance Studies) computer model.
Uses basic approximations for wind speeds, wave breaking criterion, and controlling wave height.
Detailed field reconnaissance performed to determine land use.
Aerial imagery and GPS used in a GIS (ArcMap) to locate exact shore transect locations. Components of Coastal Restudy (Continued)
Updated Wave Runup and Overtopping Analysis
RUNUP 2.0 computer program is used for runup analysis of mildly sloping shores.
ACES (Automated Coastal Engineering System) developed by the USACE is used for runup analysis of vertical or near vertical cliffs.
Updated Flood Insurance Study and DFIRMs
Approximate V and A zones will be replaced with VE and AE zones and Base Flood Elevations determined by the coastal analysis.
DFIRMs will use an Orthophoto base.
CHAMP (Coastal Hazard Analysis and Modeling Program) is a computer program that performs coastal engineering analyses for coastal flood hazard assessment. CHAMP
CHAMP analysis consists of 3 steps:
Project Info and Data Entry.
Modeling.
Summary Graphics and Tables.
Project Info and Data Entry
transect description and general transect characteristics.
Transect data entry – enter ground profile and elevation data.
Modeling
Erosion treatment – analysis of transect data for expected storm-induced erosion for quantities and geometries.
Wave Height Analysis (WHAFIS 3.0) – analysis of wave heights to estabish wave crest elevation.
Wave Runup Analysis (RUNUP 2.0) – analysis of wave runup elevation. CHAMP (Continued)
Summary Graphics and Tables
View the results of the analyses for a selected transect.
The tables The Coastal Restudy Process Flowchart St. Croix Storm Surge (in feet) Saint Thomas Storm Surge (in feet) Saint John Storm Surge (in feet) Riverine Analyses Overview
Riverine Flood Hazard Zones were determined by using Redelineation.
Redelineation defines new flood hazard zones by incorporating the best available topography into existing floodplain boundaries, modifying the flood hazard zones. DFIRM Database Example of a DFIRM Transect Database Record Preliminary Maps
After flood hazard zones have been extracted from Coastal and Riverine Analyses, Preliminary Maps are prepared and formatted into preliminary DFIRMs.
The Preliminary Maps are presented to the community representatives and the Post Preliminary phase of Map Modernization commences. Post Preliminary Map Process
Preliminary (draft) maps and study for the USVI issued 02/21/2006.
These maps and study present new Base Flood Elevations.
These elevations will be published twice in local newspapers to notify property owners of update. Post Preliminary Map Process (Continued)
Following second publication date, 90-day Appeal Period begins
Anyone may register an appeal against preliminary maps, but must be made through U.S. Virgin Islands
Appeal must be based on scientific grounds or technical information
When appeals are resolved, or if there are no appeals, a Letter of Final Determination will be issued by FEMA
Territory has six months from date of letter to amend local law to reference the new map
New BFEs become rule-making document for flood insurance and floodplain management
Final printed maps, study, and digital data distributed to users Post Preliminary Processing
Summary of Map Actions
Background
FEMA periodically issues Letters of Map Change (LOMCs)
These may be Letters of Map Amendment (LOMAs) or Letters of Map Revision (LOMRs)
LOMCs are legally binding changes to the map
Many LOMCs are not typically reflected in the new FEMA maps due to scale constraints
Some LOMCs are superceded when a new map is issued
Summary of Map Actions contains assessment of all exisiting LOMCs vis a vis the new FEMA maps Post Preliminary Processing Timeline Preliminary 1st publication 2nd publication 90 days Letter of Final Determination Effective Appeal/Protest 7 days 6 months Post Preliminary Processing Virgin Islands Timeline Preliminary 1st publication 2nd publication Feb 22 EarlyApril 90 days LFD Mid-July 2006 Effective Appeal/Protest 7 days 6 months Early 2007 When do the flood maps become effective? Conclusions
The Map Modernization Program will be an important improvement to the identification and management of flood hazards in the nation.
The benefits of the program include:
The use of advanced technologies and better data to identify actual risk.
The digital DFIRM format makes the flood hazard maps more reliable, easier-to-use, and readily available for communities, planners, and property owners.
Future updates to the DFIRMs will be less cumbersome and more flexible than the older paper maps.
Since many of the new DFIRMs utilize orthophoto basemaps, identification of individual structures and other features in relation to flood hazard zones will be more user –friendly.
The Map Mod Program in the U.S. Virgin Islands represents a significant step forward in the protection of the people and property of the Territory from the threat of wind and flood damage to lives and property. Contact Information Brian Shumon, FEMA brian.shumon@dhs.gov Paul Weberg paul.weberg@dhs.gov Jonathan Westcott, Michael Baker Engineering jonathan.westcott@mapmodteam.com