1 us army engineer research and development center fema region iii coastal mapping project may 19,...

1US Army Engineer Research and Development Center

FEMA REGION III COASTAL MAPPING PROJECT

May 19, 2011

Coastal Analyses and Outreach

Robin Danforth, FEMA Region IIIDavid Bollinger, FEMA Region III

Jeff Gangai, RAMPPChristine Worley, RAMPP

2US Army Engineer Research and Development CenterUS Army Engineer Research and Development Center

Today’s Discussion Overview and Status of Region III Coastal Study

• Why a new coastal study is needed• Storm Surge Analysis• Wave Height Analysis• Coastal Study Timeline

Outreach Efforts• Outreach Strategy• Coastal Outreach Advisory Team (COAT)• Coastal Community Meetings• Outreach Materials

Questions/Discussion


Why a Region III Coastal Study Project?

Coastal flood risk information is out-of-date

New Coastal Guidelines need to be implemented

Update base data such as topographic dataset and aerial imagery to high resolution products and seamless Digital Elevation Model (DEM)

Take advantage of higher performance numerical modeling

Take advantage of improvement in GIS technologies to allow for more accurate FIRMs


Where Will the Study Occur?

All of Region III coastal counties/cities (Atlantic Ocean Chesapeake Bay, Delaware Bay and their tributaries)


Coastal Study Process

FLOODPLAIN BOUNDARY & FLOOD HAZARD ZONE MAPPING

OVERLAND WAVE HEIGHT & RUNUP ANALYSIS

STORM-INDUCED EROSION

FRONTAL DUNE DELINEATION

FIELD RECONNAISSANCE

STARTING WAVE CONDITION ANALYSIS

STORM SURGE ANALYSIS

TERRAIN PROCESSING

6US Army Engineer Research and Development Center

Jeff Hanson Mike ForteRegion III Storm Surge Project ManagersUSACE-FRF

Region III Storm Surge Project Update


Development Phase (2008-2011)Develop and validate a storm surge modeling capability for the assessment of inundation risk in Region III

• Consistent 10-m DEM for the region• Extratropical storm wind fields• Hurricane storm hazard (JPM approach)• Integrated flood risk modeling system• Comprehensive system validation• GIS database and display capacity

Production Phase (2011)• Compute and assess the Region III flood

hazard values for 10-, 50-, 100- and 500-yr return periods

• Expected completion September 2011 Flood Levels 10-, 50-, 100-, & 500-year

Return Period Analysis- Hurricanes

- Extratropical Storms

Storm Surge Modeling

Winds

Waves Water Levels

Storm Forcing- Extratropical Wind Fields

- Hurricane TracksHigh-Res

Bathy / TopoMesh

Project Objectives


Wave Height Analysis Status Modeling set-up

• Transect Layout completed• Field Reconnaissance completed• Obstruction carding completed• Development of a seamless (topo/bathy) Digital Elevation Model

(DEM)

Wave height analysis (waiting on surge results)• Starting wave conditions (wave height and period)• Wave setup – Determined from the ADCIRC model• Dune/Bluff erosion• WHAFIS modeling for overland wave height computation• Wave Runup• Coastal Hazard Mapping


Transect Placement

Transect Layout City of Virginia Beach


Field Reconnaissance


Elements of a Coastal Floodplain


Limit of Moderate Wave Action (LiMWA) Defined by the area subject to wave action with waves

greater than 1.5 feet in height

SWEL = Stillwater ElevationBFE = Base Flood Elevation


Limit of Moderate Wave Action (LiMWA)FEMA Procedure

Memorandum No. 50, 2008

At present not a regulatory requirement

No Federal Insurance requirements tied to LiMWA

CRS benefit for communities requiring VE Zone construction standards in areas defined by LiMWA or areas subject to waves greater then 1.5 ft.


Region III Coastal Study Timeline

Surge Study Results•Fall 2011

Coastal Hazard Analysis Results•Fall 2011-Spring 2013

Preliminary DFIRMs• Spring 2012– Winter 2013

Public Comment Period•Spring 2012– Spring 2014

Letter of Final Determination•Spring 2013– Winter 2014

New Effective Coastal DFIRMs•Summer 2013 – Summer 2015


OUTREACH


Region III Coastal Outreach Strategy

Introduction Mapping Project Scope Coastal Outreach Strategy Summary Appendices

• Participating Coastal Counties/Communities• Current Mapping-Related Initiatives in Region III• Coastal Outreach Advisory Team• Key Stakeholders• Outreach Implementation Plan• Flood Risk Open House Plan


Coastal Outreach Advisory Team

The roles of the COAT:• Share local data or new

information• Relate study information

and status to other stakeholders

• Provide input on outreach methods, target groups, etc.

• Identify potential contentious issues

• Provide input on coastal study methodology


Coastal Outreach Meetings

Regional Technical Storm Surge Study Meetings

Stakeholder Meetings – COAT 5 Community Meetings per Coastal County

or City Initial Coastal Community Coordination

Meetings Flood Study Review Meetings Resilience Meetings Final Community Coordination Meetings Open Houses (Including Public)


Initial Outreach - Coastal Community Coordination Meetings

Meetings for 3 DE counties held December 2010

Meetings for all 15 coastal counties and city in MD held November 2010 – April 2011

Meetings for 13 VA coastal counties/cities held March – April 2011

Meetings for remaining 19 VA coastal counties/cities and 3 PA coastal counties TBD


Initial Outreach - Coastal Community Coordination Meetings (continued)

Meeting summaries prepared for each meeting that recorded county and community comments

Main comments: Mapping:

Multiple LFD/effective dates and thus multiple adoption periods and ordinance revisions. Some are being combined (Harford,

Caroline, Kent, Queen Anne’s, Worcester Counties, MD

Others will need to be determined (Calvert, Charles, Prince George’s and Talbot Counties, MD, Kent County, DE)

Will BFEs and floodplain widths be increased?

New VE Zones/Ordinance updates


Main comments (continued) Ordinances:

New model floodplain ordinance in MD & VA

Assistance with MD ordinances will be provided by Ed Copeland

Costs to communities: Changing ordinances Notifying property owners Answering questions

Insurance Support for insurance questions and

outreach CD with FEMA brochures and FAQs MD counties directed to

www.mdfloodmaps.org Grandfathering

Initial Outreach - Coastal Community Coordination Meetings (continued)

http://www.mdfloodmaps.org/


Coastal Study Outreach Materials

Website – www.r3coastal.com Property locator tool Outreach factsheets Outreach meetings

• PowerPoint Slides• CD Handout

http://www.r3coastal.com/


Questions/Discussion

1 us army engineer research and development center fema region iii coastal mapping project may 19,...

Documents

development centerwhy

coastal study project

army corps

status of region

new coastal study

coastal analyses

lines fema region

coastal studywhy