Post on 03-Jan-2016
North Carolina North Carolina Tar-Pamlico River Basin Tar-Pamlico River Basin
PlanPlan
Final Scoping MeetingsJanuary 30 and 31, 2001
North CarolinaNorth CarolinaCooperating Technical Cooperating Technical State Flood Mapping State Flood Mapping Program OverviewProgram Overview
Purposes of the NFIPPurposes of the NFIP
1. Make flood insuranceavailable
2. Identify floodplainareas and flood risk zones
3. Provide framework for a community’s floodplain management ordinances
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
Importance of Updated Importance of Updated Flood Hazard InformationFlood Hazard Information
North Carolina’s North Carolina’s Flood Mapping Flood Mapping
ProgramProgram 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) delegatedto State
Organization of the Organization of the CTS Flood Mapping CTS Flood Mapping
ProgramProgram
NC Center for Geographic Information
and Analysis
NCGeodetic Survey
NC Division of Emergency
Management
Federal Emergency Management Agency
OSBPM
John Dorman,Program Director/Chair
CTSCommittee
Abdul Rahmani,
Project Manager
State Floodplain Mapping
ContractorGreenhorne & O’Mara, Inc.
State Floodplain Mapping
ContractorWatershed
Concepts, Inc.
Rodger Durham,
Program Manager
Mapping Coordination Contractor
Dewberry & Davis LLC
Why North Carolina Is Why North Carolina Is Undertaking This Undertaking This
ProjectProject 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 livesand property
Why North Carolina Is Why North Carolina Is Undertaking This Undertaking This
ProjectProject 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
Benefits of North Benefits of North Carolina’s CTS Carolina’s CTS
ProgramProgram 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
Program Program ComponentsComponents
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
Digital FIRMsDigital FIRMs
Digital FIRM=
Flood DataBase + Topography +
Digital FIRMsDigital 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
Community Review and Community Review and Due ProcessDue Process
Preliminary FIRMs provided when Tar-Pamlico 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
Additional Benefits Additional Benefits of the CTS Programof 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
Tar-Pamlico River Tar-Pamlico River BasinBasin
Extends from its headwaters in the north central Piedmont section of North Carolina to the Atlantic Ocean
Most of the upstream portion (Tar River) is freshwater, whereas the downstream portion (the Pamlico River) is entirely estuarine
Comprised of portions of 19 counties and 53 municipalities
Scoping Phase for Scoping Phase for Tar-Pamlico River Tar-Pamlico River
BasinBasinThe 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
State
State
FEMA
FEMA
KickoffMeeting with County/Local
Floodplain Administrators
MappingNeeds
Assessment
EffectiveFIS & FIRM Research
EvaluatePost-Floyd
Data
NCScoping
Database
Generate Initial
Scoping Package
InitialScoping Meetings
Develop Draft Basin Plans
Final Scoping Meetings
Finalize BasinPlans
Process for Scoping Six River Basinsin 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
Step 4 — Final Scoping Step 4 — Final Scoping MeetingMeeting
THIS IS WHERE WE ARE TODAY! All impacted counties and
communities invited Two separate Final Scoping Meetings:
January 30th - Greenville, NC January 31st - Tarboro, NC
Draft Tar-Pamlico River Basin plan presented
Provides final opportunity for input
Step 5 — Final Basin PlanStep 5 — Final Basin Plan
Draft Basin Plan may be revised following the Final Scoping Meetings
Watershed Concepts, the State’s Floodplain Mapping Contractor for the Tar-Pamlico River Basin, will develop proposals for the State
Tar-Pamlico River Basin Plan will be finalized and distributed to impacted counties and communities
Production phase will then begin
North Carolina North Carolina Tar-Pamlico River Basin Tar-Pamlico River Basin
MeetingMeeting
QQUESTIONS ON THE UESTIONS ON THE SCOPING PHASESCOPING PHASE
? ? ?? ? ?
Draft Tar-Pamlico Draft Tar-Pamlico River Basin PlanRiver 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
Detailed Study — Detailed Study — RiverineRiverine
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
Riverine Areas to be Riverine Areas to be Studied in DetailStudied in Detail
(cont’d)
Riverine Areas to be Riverine Areas to be Studied in DetailStudied in Detail
(cont’d)
Riverine Areas to be Riverine Areas to be Studied in DetailStudied in Detail
(cont’d)
Riverine Areas to be Riverine Areas to be Studied in DetailStudied in Detail
(cont’d)
Riverine Areas to be Riverine Areas to be Studied in DetailStudied in Detail
RedelineationRedelineation
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
Approximate StudyApproximate 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.
Use of Effective Use of Effective InformationInformation
This method involves no new analyses or floodplain mapping
Effective FIS and FIRM data are digitized and fitted to updated base map
This method is not anticipated to be used for any communities in the Tar-Pamlico River Basin
Schedule for FIRM Schedule for FIRM ProductionProduction
(cont’d)
Schedule for FIRM Schedule for FIRM ProductionProduction
Community Review and Community Review and Due ProcessDue Process
Preliminary FIRMs provided when Tar-Pamlico 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
North Carolina North Carolina Tar-Pamlico River Basin Tar-Pamlico River Basin
MeetingMeeting
QQUESTIONS ON THE UESTIONS ON THE
DRAFT BASIN PLANDRAFT BASIN PLAN
? ? ?? ? ?