ELLIS COUNTY, TX FLOODPLAIN STUDY - PowerPoint PPT Presentation

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ELLIS COUNTY, TX FLOODPLAIN STUDY

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GIS Shape File Showing DFIRM Mapping Needs for the County ... Floodway Computations. Flood Profiles. Calibrated to Historical Events ... – PowerPoint PPT presentation

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Title: ELLIS COUNTY, TX FLOODPLAIN STUDY


1
ELLIS COUNTY, TX FLOODPLAIN STUDY
  • County Courthouse Offices
  • Waxahachie, TX
  • April 27, 2007 at 130PM

2
Scoping Meeting Agenda
  • Sign-in Sheet
  • Introduction
  • Map Modernization Studies
  • Map Production Process
  • Map Adoption Process
  • Roles FEMA Contractors
  • Levee Certification
  • Outreach / Public Awareness
  • Scoping Meeting Summary
  • DISCUSSION ----- Community Needs

3
Map Mod Studies
4
Map Modernization Program
Flood Mapping Project Phases
Preliminary DFIRM
Post Preliminary Processing
Project Scoping
Community Coordination Mapping
Needs Assessment
Topographic Data Acquisition
DFIRM Production
Time frames given are approximate and will vary
from study to study
5
Map Mod Roles - FEMA Contractors
  • FEMA Headquarters
  • Set National Policy
  • Budget Requests
  • LOMR Approval Signature
  • Congressional Liaison
  • FEMA Region VI
  • Administrate Policy
  • Manage IDIQ Contract Task Orders
  • Manage RMC Task Order
  • Outreach Public Awareness
  • National Service Provider - NSP
  • Support FEMA Headquarters
  • Procedure Memos
  • GS
  • Mapping Information Platform (MIP)
  • LOMR Processing
  • Library Data Storage
  • Regional Management Center - RMC
  • Support Region VI
  • Issue Resolution (Engineering/GIS/Mapping)
  • Receipt of Study Data
  • Quality Assurance Audit
  • Coordinate Project Management
  • Post Preliminary Processing
  • MIP Training and Data Entry
  • Outreach and Public Awareness

6
Study Contractor Task Orders
  • Scoping Task Order
  • Scoping Meeting
  • Base Map Ortho vs. Vector
  • Proposed Panel Scheme
  • Scoping Meeting Report
  • GIS Shape File Showing DFIRM Mapping Needs for
    the County
  • DFIRM and Flood Insurance Study Task Order
  • Digital Flood Insurance Rate Map
  • Update Flood Insurance Study Text
  • Address mapping needs up to limit of budget
  • Update Community on study negotiated scope
  • Update Community on progress of study

7
Halff Associates, Inc. Study Contractor
  • Walter Skipwith, PE
  • wskipwith_at_halff.com
  • Jessica Baker, EIT, CFM
  • jbaker_at_halff.com
  • Halff Associates, Inc.
  • 8616 Northwest Plaza Dr.
  • Dallas, Texas 75225
  • (214) 346-6200 Office
  • (214) 273-1307 Fax

8
What and Why Are We Scoping?
  • Information Search
  • Coordination / Outreach
  • Assess Community Mapping Needs

9
Map Modernization 1834 Style (Pre-FIRM)
10
Map Modernization 2007 Style DFIRM Product
11
Overall Scoping Study
12
Scoping Activities
13
Pertinent Data on Ellis County
  • Area 952 Sq. Mi.
  • Density 135 Persons/Sq. Mi.

14
Pertinent Data on Ellis County
  • 36 Existing FIRMs (Printed)
  • Scales 1500, 1000, and 2000
  • Average Panel Age 8 Years
  • Flood Insurance Policies in Place 606
  • LOMCs 45
  • Claims 397 (7,794,740)

15
Ellis County Re-Study
  • Scoping
  • 191 miles of Detail Study (Zone AE)
  • 908 miles of Approximate Study (Zone A)
  • 32 Proposed FIRMs

16
The Study Process
  • Information Search
  • Base Map and Terrain Data Acquisition
  • Field Survey
  • Hydrology
  • Hydraulics
  • Mapping
  • Reporting (TSDN)
  • Coordination /Outreach

17
Base Mapping
  • Local Provided Planimetrics
  • USDA National Agricultural Imagery Program (NAIP)
  • USGS Contours Supplemented with Local Data

Local High Resolution Data
USGS 7.5 Minute Quads
USGS DOQQ
18
Terrain Information
  • Terrain Map Sources
  • Local Data
  • USGS Contour Maps 30 M DEMs
  • LiDAR
  • Formats
  • Digital (GIS Shapefiles, AutoCAD Files)
  • Hardcopy

USGS 7.5 Minute Quads
Local High Resolution Data
USGS 30M DEM
19
DATUM NAVD 88 / NAD 83
  • The majority of existing FIRM panels vertical
    datums
  • National Geodetic Vertical Datum (NGVD) 29
  • Local Datum
  • New DFIRM Panel datums will be standardized to
  • Vertical - North America Vertical Datum of 1988
    (NAVD 88)
  • Horizontal North American Datum of 1983 (NAD 83)

20
Possible Mapping Products Available
  • New Detailed Study
  • Enhanced Approximate Study
  • Redelineation of Existing Detailed Study
  • Approximate Study (Zone A Refinement)
  • Digital Conversion

21
New Detailed Study
  • Field Survey
  • New Topo/Orthophoto
  • Detailed Hydrologic and Hydraulic Modeling
  • Floodway Computations
  • Flood Profiles
  • Calibrated to Historical Events
  • Most Expensive Type of Study

22
Sample of Detail Study Stream
  • Cross-Sections
  • BFEs
  • Floodways

23
Enhanced Approximate Study
  • Limited Detailed Study
  • No (or) Limited Structure Surveys
  • No (or) Limited Floodways
  • No (or) Limited Profiles
  • Advantages
  • Cost is Much Less Than Detailed Study
  • More Streams Can Be Studied

24
Redelineation Streams
  • Applies to Existing Detailed Study Streams (Zone
    AE)
  • Vertical Datum Update from 1929 to 1988
  • Flood Boundaries Mapped to the Best Available
    Topography

25
Zone AE Redelineation
26
Approximate Study
  • Zone A Refinement
  • Automated HH Procedures
  • Boundaries Mapped to Best Available Topography

27
Sample of Existing Zone A
100-yr Boundary
Stream Centerline
28
Zone A Refinement
29
Digital Conversion
  • Utilize the Existing Flood Zone Information
  • Advantages Low Cost Solution
  • Disadvantages Boundaries may not agree with the
    best available topographic data

30
Floodplain Mapping
31
DFIRM Database
Digital FIRM
32
DFIRM Vector vs. Ortho Based
33
DFIRM Vector vs. Ortho Based
Vector Based
Ortho Based
34
Ellis County Effective FIRM Panel Layout
36 Effective Panels
35
Ellis County Proposed DFIRM Panel Layout
32 Proposed Panels
36
Technical Support Data Notebooks (TSDNs)
  • Notebooks
  • Scoping Report
  • Topographic Data
  • Base Map
  • Hydrology
  • Hydraulics
  • DFIRM
  • Final
  • Complete Documentation of the Project
  • Contacts
  • Meeting Minutes
  • Data
  • Analyses Assumptions
  • Other Information as needed

37
FIS Report
  • Countywide Flood Insurance Study
  • Text
  • Profiles
  • Data Tables

38
Halff FEMA Re-Study Website Hotline
www.halff-femastudy.com Hotline 1(877) HALFF-TX
39
Levees Protection with Risk
  • Levees are designed to provide specific level of
    protection
  • They can be overtopped or fail in larger flood
    events
  • They require regular maintenance and periodic
    upgrades to retain their level of protection
  • FEMA urges people to understand their flooding
    risk involving levees

40
Levee Ownership
  • FEMA does not own, operate, maintain or certify
    any levees
  • FEMA can accredit a levee certification provided
    by others
  • The levee owner can certify the design,
    construction, operation and maintenance of a
    levee
  • Community is benefiting from the levee

41
FEMA Requirements
  • FEMAs certification requirements for Levee
    Design, Construction, Operation and Maintenance
    to gain FEMA Accreditation.
  • A. Certification Standard is 44 CFR 65.10
  • Certification checklist is based on requirements
    from 44 CFR 65.10.
  • Revised date is October 1, 1999.
  • B. Procedure Memorandum No. 34 (PM
    34)-Certifcation Documents are available to
    submit within 30 days.
  • Interim Guidance for Studies Including Levees
  • August 22, 2005
  • C. Procedure Memorandum No. 43 (PM 43)-Need time
    to gather certification documents-24 months
    allowed.
  • Guidelines for Identifying Provisionally
    Accredited Levees
  • September 25, 2006
  • Revised March 16, 2007

42
44 CFR 65.10 Highlights
  • To be certifiable, the levee system must be owned
    and operated by a public entity
  • The levee owner has the ultimate responsibility
    of certifying the levee
  • Design and Construction requirements
  • Freeboard, Foundation, etc.
  • Operation and Maintenance requirements
  • OM manual, maintenance records, etc.
  • Federal Agency (USACE) who constructed levee can
    provide certification
  • Levee must be certified/re-certified every time
    the map is changed

43
44 CFR 65.10
44
PM 34 Highlights
  • Interim guidance to establish certification
    process (flowchart)
  • Specifies that levee systems that are mapped by
    FEMA are designed, constructed, operated and
    maintained to standards (44 CFR 65.10)
  • Requires obtaining verification that
    certification requirements are and continue to be
    met
  • Requires that necessary certifications are
    provided by the responsible party

45
PM 34
46
PM 43 Highlights
  • Created to prevent levee issues from holding up
    DFIRMs
  • Allows 2 years to compile certification
    documentation
  • Not allowed for any levee that requires any
    construction work to be done for certification
  • Public versus Privately owned levees (PAL
    Scenario)
  • PAL Agreement

47
PM 43 and Guidance 25
48
Levee Checklist
49
FEMA Accreditation of Certification
  • If adequate certification is provided and
    accepted, FEMA will accredit the levee as
    providing protection
  • If levee certification is not provided, the area
    will be mapped with the levee NOT providing
    protection

50
Post Preliminary andMap Adoption Process
  • Presentation of Preliminary DFIRM to Community
    (also known as CCO Meeting)
  • 90-Day Appeal Period
  • Appeal Resolution
  • Letter of Final Determination (LFD)
  • 6 Month Compliance (Map Adoption) Period
  • Final adoption and/or revision of Floodplain
    Management Ordinance
  • Effective DFIRM

51
Ordinance Assistance
  • Primary Resource TFMA
  • FEMA Region VI
  • Sample Model Ordinances
  • Ordinance Checklist
  • Suggestions for Higher Standards
  • Application to join NFIP

52
Outreach
  • We all do Outreach
  • In our field of expertise.

53
Outreach
  • Technical Community Study Contractor
    communicates with community through scoping
    meetings, information meetings, periodic written
    status reports, web sites, etc.
  • State NFIP Coordinators State Associations
    Lenders Insurance Agents via FEMA Region 6
    through meetings, correspondence, conferences,
    special announcements, etc.
  • Public Officials via FEMA Region 6 communicates
    directly with community officials providing
    assistance in ordinance development and map
    adoption.
  • General Public via FEMA Region 6 Public
    Awareness providing information and materials for
    distribution to alert the public of new study
    efforts, issuance and availability of Preliminary
    DFIRMs, appeals process, and community map
    adoption.

54
FEMA Public Awareness
  • Provide Public Awareness materials
  • Assist in keeping the public informed
  • Assist in obtaining publications regarding Map
    Modernization
  • Designated Point of Contact will be provided
    information and/or materials as needed or
    requested

55
Memorandum of Agreement (MOA)
  • Community Partner MOA
  • Says that you know the study is occurring and
    will cooperate with FEMA
  • This document is similar to the resolution that
    was originally signed by the community upon entry
    into the NFIP.

56
Scoping Meeting Summary
  • Completed Sign-In Sheet
  • Answered questions regarding Study Process
  • Identified available data pertinent to the study
  • Decided Base Map Type
  • Decided Paneling Scheme for Countywide Study
  • Obtained Priorities from Communities
  • Obtained Point of Contact for Public Awareness
    materials
  • Distributed Memorandum of Agreement between FEMA
    and Communities

57
Community Needs Discussion

58
  • Thank you for your time and input

59
Contacts
  • FEMA
  • Lynn Hilburn COTR
  • howard.l.hilburn_at_dhs.gov
  • Ph (940) 898-5165
  • Shari Brand Public Outreach Coordinator
  • shari.brand_at_dhs.gov
  • Ph (940) 898-5358
  • Dale Hoff Compliance Specialist
  • Dale Hoff_at_dhs.gov
  • Ph (940) 898-5128

State NFIP Coordinator Mike Howard
mhoward_at_tnrcc.state.tx.us Ph (512)
239-6155 Study Contractor Walter
Skipwith wskipwith_at_halff.com Ph (214)
346-6220 Jessica Baker jbaker_at_halff.com Ph
(214) 217-6692 RMC Contact Steve Altman
saltman _at_mbakercorp.com Ph (940) 783-4155
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