updating georgia’s coastal maps: collaboration on my mind
TRANSCRIPT
Updating Georgia’s Coastal Maps Collaboration on my Mind
June 2, 2015
Onur Celik, PE, CFM, CDM Smith
Todd Harris, PMP, CFMGeorgia Department of Natural Resources
Outline
• Project Overview– History– Scope– Collaborating Parties– Outreach
• Analyses and Mapping Approach– Coastal Analysis– Riverine Analysis– Mapping/Regulatory Products– Non-Regulatory Products
• Conclusion – Q/A
History – Georgia Flood M.A.P. Program
• Increase focus on risk assessment and planning
• Continue partnerships with Federal, State, and Local Agencies
• Acquire and utilize high accuracy topo data
• Deliver risk products and datasets
Enhanced Outreach Program• Outreach Guidebooks
• Increased Community Engagement
• Robust Website (www.georgiadfirm.com)
Transitioning State Program to align with FEMA’s Risk MAP Program
History
• Effective Coastal Studies are dated– Current surge analysis is 20 to 40+ years old!
Chatham County – ESSA’S JPM Method (1970)
Climate data from 1965 to 1981Glynn and Camden Counties – SURGE
model update in 1989
• Riverine Studies are partially up-to dateBryan, Charlton, Effingham, Liberty, Long, Chatham partially updated in 2014Camden, Glynn, McIntosh analyses were older and did not utilize the current LiDAR data or latest hydraulic models
History
– FEMA Funded Risk MAP projects for 10 Counties in Eastern/Coastal Georgia:
• Bryan• Camden• Charlton• Chatham• Effingham• Glynn• Liberty• Long• McIntosh• Newton
Scope
Complete (Inland):– Completed:
In Progress (Coastal):
Collaborating Parties
– FEMA contracted AECOM/Baker for Coastal Analyses
– Georgia DNR contracted CDM Smith and Dewberry for Riverine Analyses, Production
– Inland Riverine Analyses completed andinland counties became effective in 2014
– Coastal Analyses are complete in Spring
- Preliminary Maps will be issued tentativelyin September
Outreach
DiscoveryMulti-Agency Coordination
Meeting
Kick-off (Coastal Update) Meeting
H&H-Coastal Modeling
Flood Risk Review
Meetings
Preliminary FIRMs & FIS
MARCH 2012 FEB. 2013 FALL 2014 AUG. 2015 SEP. 2015MAY 2014
FALL 2015
PRELIMINARY PROCESSING
POST PRELIMINARY PROCESSING
FEMA issues Letter of Final Determination
Six Month Compliance
Period (Ordinance Updates)
Resilience Meeting
CCO Meeting 90-Day Appeal Period
FEMA & GA DNR resolve appeals &
protests
COMMUNITY MEETINGS
Outreach – Upcoming Flood Study Review Meetings
Outreach – Property Notification Tool
Analyses and Mapping Approach
• Study Types:– Coastal
– VE or AE Zones– LiMWA
– Riverine– Detailed/Limited Detailed– Redelineation– Approximate
Coastal Analyses
Determined from storm surge model
Components of Coastal Flooding:1. Storm Surge Stillwater Elevation (SWEL)2. Wave Setup3. Wave Height4. Wave Runup
Coastal Analyses – Storm Surge
• Set up “mesh” for hurricane/surge model
• Validated hurricane/surge model
• Ran hundreds of hypothetical storms
• Resulting storm surge still water elevations for the 1% annual chance event
Coastal Analyses
Coastal Analyses – Mapping
Riverine Analyses
37131.0500
35257.940035037.9400
– Types of Analyses– Detailed/Limited Detailed– Redelineation– Approximate
Riverine Analyses
12 00 14 00 16 00 18 00 20 00 22 00 24 00 26 00
76
78
80
82
84
Beaverdam Swamp- Approximate Study RS = 54 448.14
Station (ft)
Ele
vatio
n (f
t)
Le gend
WS 100yr
Ground
Ineff
Bank Sta
.12 .06
.12
Regulatory Products
• Upcoming FIRM and FIS Report will follow new Specifications:
Regulatory Products – FIS Report
• Database Driven and more User Friendly
Old Format New Format
Regulatory Products – FIS Report
• Map Index in the report for easy reference
• Information for 4% (25 Year) Flood (where available):
Regulatory Products – FIS Report
• Future Conditions (if applicable)
• Protection Measures:
Regulatory Products – FIRM
• Additional Information (Elevations at 1/10’ increments etc)• New Look, more streamlined legend
Old Format New Format
Regulatory Products – FIRM
• User Friendly
Regulatory Products – FIRM
• Additional Information (Elevations at 1/10’ increments etc)• New Look, more streamlined legend
Old Format New Format
Non-Regulatory Product – Changes Since Last FIRM
• First Time in Georgia• Provides information to be used for Mitigation/Outreach Activities
Non-Regulatory Product – Flood Depth Grid
• First Time in Georgia• Provides information to be used for Mitigation/Outreach Activities
Non-Regulatory Product – Wave Height Grid
• First Time in Georgia• Provides information to be used for Mitigation/Outreach Activities
Example: Wave Height Grid
Non-Regulatory Product – Risk Assessment Grid
• First Time in Georgia• Provides information to be used for Mitigation/Outreach Activities
Non-Regulatory Product – AOMI
• First Time in Georgia• Provides information to be used for Mitigation/Outreach Activities
Conclusion
Preliminary by September 30
Questions/Comments???
Todd Harris, GADNR, [email protected]
Onur Celik, CDM Smith, [email protected]