Transcript No Slide Title

North Carolina
Tar-Pamlico River Basin Plan
Final Scoping Meetings
January 30 and 31, 2001
North Carolina
Cooperating Technical State
Flood Mapping Program
Overview
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
Importance of Updated Flood
Hazard Information

With up-to-date flood hazard data:

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Map users can make prudent siting,
design, and flood insurance purchase
decisions
Communities can administer sound
floodplain management programs
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
Organization of the CTS
Flood Mapping Program
OSBPM
John Dorman,
Program Director/Chair
CTS
Committee
NC Center for
Geographic Information
and Analysis
NC
Geodetic Survey
NC Division of
Emergency
Management
Federal Emergency
Management Agency
Rodger Durham,
Abdul Rahmani,
Program Manager
Project Manager
Mapping
Coordination
Contractor
Dewberry &
Davis LLC
State Floodplain
Mapping
Contractor
Greenhorne &
O’Mara, Inc.
State Floodplain
Mapping
Contractor
Watershed
Concepts, Inc.
Why North Carolina Is
Undertaking This Project

State’s vulnerability to hurricanes
and flooding

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
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
Why North Carolina Is
Undertaking This Project

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Hurricane Floyd revealed flood hazard data
and map limitations
Age of North Carolina FIRMS

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
FEMA’s mapping budget is finite

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55% at least 10 years old
75% at least 5 years old
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
Carolina’s CTS Program



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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 Components
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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 FIRMs
+
Base
=
Topography
+
Flood Data
Digital
FIRM
Digital FIRMs

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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
Due Process

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Preliminary FIRMs provided when TarPamlico 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 of
the CTS Program

Digital format to allow:
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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 Basin
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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
Tar-Pamlico 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
SCOPING
PRODUCTION
Step 1
Step 2
Step 3
Step 4
Step 5
Initial Research
and Community
Coordination
Initial
Scoping
Meeting
Draft
Basin
Plans
Final
Scoping
Meeting
Final Basin
Plans
Initial
Scoping
Meetings
Develop
Draft
Basin
Plans
Final
Scoping
Meetings
State
Kickoff
Meeting with
County/Local
Floodplain
Administrators
Questionnaire
State
Mapping
Needs
Assessment
NC
Scoping
Database
Generate
Initial
Scoping
Package
Finalize
Basin
Plans
FEMA
Effective
FIS & FIRM
Research
FEMA
Evaluate
Post-Floyd
Data
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 4 — Final Scoping Meeting
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THIS IS WHERE WE ARE TODAY!
All impacted counties and communities
invited
Two separate Final Scoping Meetings:
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January 30th - Greenville, NC
January 31st - Tarboro, NC
Draft Tar-Pamlico River Basin plan
presented
Provides final opportunity for input
Step 5 — Final Basin Plan
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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
Tar-Pamlico River Basin
Meeting
QUESTIONS ON THE
SCOPING PHASE
???
Draft Tar-Pamlico
River Basin Plan
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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 — Riverine
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This method requires the following:
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DEMs
Field surveys
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Channel bathymetry
Bridge/culvert opening geometry
Channel and floodplain characteristics
Detailed Hydrologic and Hydraulic Analyses
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10%, 2%, 1%, and 0.2% annual chance flood
elevations and boundaries identified (Zone AE)
Floodways delineated
Riverine Areas to be
Studied in Detail
Approx.
Flooding
Source
County
Reach Description
Beech Branch
Edgecombe
From its confluence with the Tar River to a point approximately 9.3
miles upstream of confluence.
9.3
Broad Creek
Tributary
Beaufort
From its confluence with Broad Creek to a point approximately 1.6
miles upstream of confluence.
1.6
Chicod Creek
Pitt
From a point approximately 3.3 miles upstream of its confluence with
the Tar River to a point approximately 7.1 miles upstream of
confluence.
3.8
Cokey
Swamp
Edgecombe
From a point approximately 1.6 miles upstream of its confluence with
Town Creek to a point approximately 8.7 miles upstream of confluence
7.1
Compass
Creek
Edgecombe
From confluence with the Tar River to a point approximately 7.4 miles
upstream of confluence
7.4
Coon Creek
(Northern)
Granville
From confluence with Jordan Creek to a point approximately 4.2 miles
upstream of confluence
4.2
Coon Creek
(Southern)
Granville
From confluence with Fishing Creek to a point approximately 3.3 miles
upstream of confluence.
3.3
Deep Creek
Edgecombe
From confluence of Savage Mill Run to a point 1.6 miles upstream of
confluence
1.6
East Tarboro
Canal
Edgecombe
From confluence with the Tar River to a point approximately 2.0 miles
upstream of confluence
2.0
Fishing Creek
Halifax
From State Highway 1418 to a point approximately 9.3 miles upstream
of State Highway 1418.
9.3
Fishing Creek
Tributary 1
Granville
From a point approximately 240 feet downstream of Hillsboro Street to
a point approximately 980 feet upstream of Cherry Street.
0.6
Reach Length
(miles)
(cont’d)
Riverine Areas to be
Studied in Detail
Approx.
Flooding
Source
County
Reach Description
Goose Branch
Edgecombe
From confluence with the Tar River to a point approximately 2.6 miles
upstream of confluence.
2.6
Grape Branch
Edgecombe
From confluence with the Tar River to a point approximately 0.6 mile
upstream of confluence.
0.6
Green Mill Run
Pitt
From confluence with the Tar River to a point approximately 8.3 miles
upstream of confluence.
8.3
Grindle Creek
Pitt
From confluence with the Tar River to a point approximately 7.3 miles
upstream of confluence
7.3
Hardee Creek
Pitt
From the State Highway 1726 to a point approximately 0.3 mile
upstream of State Highway 1726.
0.3
Hardee Creek
Pitt
From confluence with the Tar River to a point approximately 4.6 miles
upstream of confluence.
4.6
Hendricks
Creek
Edgecombe
From confluence with the Tar River to a point approximately 2.4 miles
upstream of confluence.
2.4
Hornbeam
Branch
Edgecombe
From confluence with Compass Creek to a point approximately 4.2 miles
upstream from confluence.
4.2
Johnson Creek
Granville
From a point approximately 0.8 miles downstream of the confluence of
Aycock Creek to a point approximately 2.4 miles upstream of the
confluence.
3.2
Johnson Mill
Run
Pitt
From confluence with the Tar River to a point approximately 2.3 miles
upstream of confluence.
2.3
Juniper Branch Pitt
From confluence with Chicod Creek to a point approximately 3.9 miles
upstream of confluence
3.9
Reach Length
(miles)
(cont’d)
Riverine Areas to be
Studied in Detail
Approx.
Flooding
Source
County
Reach Description
Knight Swamp
Edgecombe
From confluence with Deep Creek to a point approximately 1.7
miles upstream of confluence.
1.7
Little Cokey
Swamp
Edgecombe
From a point approximately 0.5 miles upstream of its
confluence with Cokey Swamp to a point approximately 2.1
miles upstream of confluence with Cokey Swamp.
1.6
Maple Branch
& Mitchell
Branch
Beaufort
Both segments are from their confluence with Tranters Creek
to points approximately 2.1 miles upstream of the confluences.
4.2
Maple Creek
Edgecombe
From confluence with the Tar River to a point approximately
2.0 miles upstream of confluence.
2.0
NC 42 Canal
Edgecombe
From a point approximately 1,600 feet downstream of NC 42 to
a point approximately 0.5 mile upstream of NC 42.
0.8
North Fork of
the Tar River
Granville
From its confluence with the Tar River to a point approximately
7.7 miles upstream of confluence.
7.7
Runyon Creek
Beaufort
From confluence with the Tar River to a point approximately
2.1 miles upstream of confluence.
2.1
Shelton Creek
Granville
From its confluence with the Tar River to a point approximately
11.6 miles upstream of confluence.
11.6
Stoney Creek
Edegecombe
From confluence with the Tar River to a point approximately
11.8 miles upstream of confluence.
11.8
Tar River
Edgecombe
From confluence of Harts Mill Run to a point approximately 0.5
mile upstream of the confluence of Tar River Tributary.
16.4
Tar River
Edgecombe
From the confluence of Town Creek to the upstream county
boundary.
45.0
Reach Length
(miles)
(cont’d)
Riverine Areas to be
Studied in Detail
Approx.
Flooding
Source
County
Reach Description
Tar River
Granville
From the eastern county boundary to a point approximately 4.3
miles upstream of the eastern county boundary.
Tar River
Granville
From a point approximately 0.9 miles downstream of the
confluence of Owen Creek to 12.6 miles upstream of the
confluence.
Tar River
Nash
From a point approximately 0.6 miles upstream of confluence of
Sapony Creek to a point approximately 5.3 miles upstream of
the confluence.
4.8
Tar River
Pitt
From a point approximately 6.1 miles downstream of the
confluence of Harris Mill Run to the confluence.
6.1
Tar River
Pitt
From the county boundary to a point approximately 14.2 miles
upstream of the county boundary.
14.2
Tar River
Pitt
From the confluence of Johnsons Mill Run to a point
approximately 12.9 miles upstream of the confluence.
12.9
Town
Creek
Edgecombe
From a point approximately 1.7 miles upstream of its confluence
with Cokey Swamp to a point 8.6 miles upstream of the
confluence.
6.9
Town
Creek
(North of
Elm City)
Wilson
From a point approximately 1,800 feet downstream of Bottoms
Dairy Road to a point approximately 2.0 miles upstream of
Bottoms Dairy Road.
2.3
Tranters
Creek
Pitt
From Arbor Bluff Road to a point approximately 13.0 miles
upstream of Arbor Bluff Road.
Tributary A
Edgecombe
From its confluence with Hendricks Creek to a point
approximately 1.2 miles upstream of the confluence.
Reach Length
(miles)
4.3
13.7
13.0
1.2
(cont’d)
Riverine Areas to be
Studied in Detail
Approx.
Flooding
Source
Reach Length
(miles)
County
Reach Description
Tributary B of
Hendricks
Creek
Edgecombe
From a point approximately 2.4 miles upstream of its confluence
with Hendricks Creek to a point approximately 3.9 miles upstream
of the confluence.
Unnamed
Tributary of
Holly Creek
Edgecombe
From confluence with Holly Creek to a point approximately 2.1
miles upstream of the confluence.
2.1
From State Highway 1203 to a point approximately 0.9 miles
upstream of State Highway 1203.
0.9
Upper Tar
River
Total
Vance
1.5
278.7
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
Approximate Study

This method requires the following:



DEMs
Delineation of 1% annual chance floodplain
boundaries using approximate methods
Does not include collection/use of fieldcollected 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
Information


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
Production
County
FIRM
Panels in TarPamlico
Basin
Projected
Preliminary
Date for TarPamlico
Portion
Other Basin(s)/
Projected Preliminary
Date
Beaufort
170
August 2001
Neuse River (August 2002)
Craven
5
August 2001
Neuse River (August 2002)
Dare
8
February 2002
Edgecombe
110
August 2001
N/A
Franklin
64
August 2001
Neuse River (August 2002)
Granville
56
August 2001
Neuse River (February 2002)
Roanoke River (Est. 2003)
Halifax
80
August 2002
Roanoke River (Est. 2003)
Hyde
66
August 2001
Martin
12
August 2001
Roanoke River (Est. 2003)
Nash
77
August 2001
Neuse River (August 2002)
Pasquotank River
(February 2002)
Pasquotank River
(February 2002)
(cont’d)
Schedule for FIRM
Production
County
FIRM
Projected
Panels in Tar- Preliminary Date
Pamlico
for Tar-Pamlico
Basin
Portion
Other Basin(s)/
Projected Preliminary Date
Pamlico
18
August 2002
Neuse River (August 2002)
Person
5
February 2002
Pitt
80
August 2001
Neuse River (August 2002)
Vance
16
August 2001
Roanoke River (Est. 2003)
Warren
24
August 2001
Roanoke River (Est. 2003)
Wilson
8
August 2001
Neuse River (August 2002)
Neuse River (February 2002)
Roanoke River (Est. 2003)
Community Review and
Due Process

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Preliminary FIRMs provided when TarPamlico 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
Tar-Pamlico River Basin
Meeting
QUESTIONS ON THE
DRAFT BASIN PLAN
???