1. North Carolina Lumber River Basin Plan
North Carolina CTS Flood Mapping Program
North Carolina Lumber River Basin Plan
Final Scoping Meetings
January 4 and 5, 2001
January 2, 2001

2. North Carolina CTS Flood Mapping Program
North Carolina Cooperating Technical State Flood Mapping Program Overview
January 2, 2001

3. North Carolina CTS Flood Mapping Program
Purposes of the NFIP
1. Make flood insurance available
2. Identify floodplain areas and flood risk zones
3. Provide framework for a community’s floodplain management ordinances
January 2, 2001

4. Importance of Updated Flood Hazard Information
North Carolina CTS Flood Mapping Program
Importance of Updated Flood Hazard Information
With up-to-date flood hazard data:
Map users can make prudent siting, design, and flood insurance purchase decisions
Communities can administer sound floodplain management programs
January 2, 2001

5. North Carolina’s Flood Mapping Program
North Carolina CTS Flood Mapping Program
North Carolina’s Flood Mapping Program
Program established to implement the Cooperating Technical State (CTS) Partnership with FEMA, signed September 15, 2000
Ownership and responsibility for Flood Insurance Rate Maps (FIRMs) delegated to State
January 2, 2001

6. Organization of the CTS Flood Mapping Program
North Carolina CTS Flood Mapping Program
Organization of the CTS Flood Mapping Program
January 2, 2001

7. Why North Carolina Is Undertaking This Project
North Carolina CTS Flood Mapping Program
Why North Carolina Is Undertaking This Project
State’s vulnerability to hurricanes and flooding
14 federally declared disasters since 1989
Hurricane Floyd damages = $3.5 billion
4,117 uninsured/under-insured homes destroyed as result of Hurricane Floyd
Accurate, up-to-date flood hazard information crucial to protect lives and property
January 2, 2001

8. Why North Carolina Is Undertaking This Project
North Carolina CTS Flood Mapping Program
Why North Carolina Is Undertaking This Project
Hurricane Floyd revealed flood hazard data and map limitations
Age of North Carolina FIRMS
55% at least 10 years old
75% at least 5 years old
FEMA’s mapping budget is finite
North Carolina receives only one updated flood study for one county per year
Many counties and communities lack resources to take on this responsibility
January 2, 2001

9. Benefits of North Carolina’s CTS Program
North Carolina CTS Flood Mapping Program
Benefits of North Carolina’s CTS Program
Current, accurate data for sound siting and design decisions
Better floodplain management to reduce long-term flood losses
Updated data to alert at-risk property owners of the need for flood insurance
Faster, less expensive FIRM updates
January 2, 2001

10. North Carolina CTS Flood Mapping Program
Program Components
Developing flood hazard studies through community mapping needs analysis (Scoping)
Acquiring high-resolution topographic data and accurate Digital Elevation Models (DEMs)
Conducting engineering studies
Generating countywide digital FIRMs (DFIRMs)
Designing and implementing state-of-the-art, dynamic IT infrastructure
Supporting real-time flood forecasting and inundation mapping capability
January 2, 2001

11. North Carolina CTS Flood Mapping Program
Digital FIRMs
Base +
Topography +
Flood Data
Digital FIRM =
January 2, 2001

12. Digital FIRMs Digital FIRMs will be produced in a countywide format
Will depict all flood hazard data
FIRM panels will be consistent with USGS DOQ tiling scheme

13. Community Review and Due Process
Preliminary FIRMs provided when Lumber River Basin Study is complete
90-day appeal period
Preliminary Countywide FIRMs provided when adjacent basin studies are complete
All appeals evaluated and resolved
Final Effective FIRMs provided and made available by the State on its Information Management System

14. Additional Benefits of the CTS Program
North Carolina CTS Flood Mapping Program
Additional Benefits of the CTS Program
Digital format to allow:
More efficient, precise flood risk determinations
Geographic Information System (GIS) analysis and planning
Online access 24 hours a day
DEMs will be useful for almost any engineering or planning application
January 2, 2001

15. Lumber River Basin
Located in the southern coastal and piedmont plains of North Carolina
Includes 4 separate river drainage systems (Lumber and Waccamaw Rivers and tributaries, Little Pee Dee River Headwaters, and Coastal Area watershed)
Comprised of portions of 10 counties and 53 municipalities

16. Scoping Phase for Lumber River Basin
The Scoping Phase determines:
What areas are floodprone and need flood hazard data developed
Determine appropriate technical method for developing up-to-date flood hazard data and establish priority level
How flood hazard data will be presented on FIRMs

17. North Carolina CTS Flood Mapping Program
State
FEMA
Kickoff Meeting with County/Local Floodplain Administrators
Mapping Needs Assessment
Effective FIS & FIRM Research
Evaluate Post-Floyd Data
NC Scoping Database
Generate Initial Scoping Package
Initial Scoping Meetings
Develop Draft Basin Plans
Final Scoping Meetings
Finalize Basin Plans
Process for Scoping Six River Basins in Eastern North Carolina
Prepare Delivery Orders & CTC Mapping Activity Agreements & Update CTS Mapping Agreement
Analysis and Mapping
Step 1
Initial Research and Community Coordination
Step 2
Initial Scoping Meeting
Step 3
Draft Basin Plans
Step 4
Final Scoping Meeting
Step 5
Final Basin Plans
SCOPING
PRODUCTION
Questionnaire
North Carolina CTS Flood Mapping Program
January 2, 2001

18. Step 4 — Final Scoping Meeting
THIS IS WHERE WE ARE TODAY!
All impacted counties and communities invited
Two separate Final Scoping Meetings:
January 4th - Bolivia, NC
January 5th - Laurinburg, NC
Draft Lumber River Basin plan presented
Provides final opportunity for input

19. Step 5 — Final Basin Plan
Draft Basin Plan may be revised following the Final Scoping Meeting
Greenhorne & O’Mara, the State’s Floodplain Mapping Contractor for the Lumber River Basin, will develop proposals for the State
Lumber River Basin Plan will be finalized and distributed to impacted counties and communities
Production phase will then begin

20. North Carolina Lumber River Basin Meeting
QUESTIONS ON THE SCOPING PHASE
? ? ?

21. Draft Lumber River Basin Plan
Summarizes scoping phase
Outlines how base maps and topography will be acquired
Proposes engineering methods by which each flooding source reach will be studied
Describes the process and schedule for completing the map production

22. Detailed Study — Riverine
This method requires the following:
DEMs
Field surveys
Channel bathymetry
Bridge/culvert opening geometry
Channel and floodplain characteristics
Detailed Hydrologic and Hydraulic Analyses
10%, 2%, 1%, and 0.2% annual chance flood elevations and boundaries identified (Zone AE)
Floodways delineated

23. Riverine Areas to be Studied in Detail
(cont’d)

24. Riverine Areas to be Studied in Detail
(cont’d)

25. Riverine Areas to be Studied in Detail
(cont’d)

26. Riverine Areas to be Studied in Detail

27. Detailed Study — Coastal
This method produces the following:
Floodplain mapping for areas along open coast and embayments
Designations as Zones AE or VE

28. Redelineation This method requires the following:
DEMs
Effective FIS flood elevations
Proposed for all areas currently shown on effective FIRM as Zone AE or VE and not being restudied

29. Approximate Study This method requires the following:
DEMs
Delineation of 1% annual chance floodplain boundaries using approximate methods
Does not include collection/use of field-collected topographic data or bridge/culvert data
Proposed for all areas currently shown on effective FIRM as Zone A and not being restudied in detail.

30. Use of Effective Information
This method involves no new analyses or floodplain mapping
Effective FIS and FIRM data is digitized and fitted to updated base map
This method is not anticipated to be used for any communities in the Lumber River Basin

31. Schedule for FIRM Production

32. Community Review and Due Process
Preliminary FIRMs provided when Lumber River Basin Study is complete
90-day appeal period
Preliminary Countywide FIRMs provided when adjacent basin studies are complete
All appeals evaluated and resolved
Final Effective FIRMs provided and made available by the State on its Information Management System

33. North Carolina Lumber River Basin Meeting
QUESTIONS ON THE
DRAFT BASIN PLAN
? ? ?