Flood Insurance Study

Transcription

1 Flood Insurance Study Grant County, Arkansas Status Meeting November 17, 2010, 2pm Grant County OES/EOC 130 Grant 74, Sheridan, AR

2 Presentation Overview Introduction FEMA Risk MAP Update Study Discussion Future Steps Questions 2

3 Introduction Introduction of participants Name Community Your Department Your Role/Title Please make sure that you sign in 3

4 Introduction Why are we here? We would like to update you on study progress and schedule since our last visit Communicate intent and findings

5 Introduction FY2009 transition from Map Modernization (Map MOD) to FEMA Risk MAP Three focus areas Coastal Levees Other engineering needs 5

6 FEMA Risk Mapping Assessment Planning Update Map Modernization used increasinglyavailable technology to increase the quality, reliability and availability of flood hazard maps and data It focused on creating digital maps to provide timely, accurate information to community planners Risk MAP further enhances the maps, involves communities during the assessment and planning stages, and guides and encourages them to communicate risk to their constituents 6 6

7 FEMA Risk MAP Update Through collaboration with State, Local, and Tribal entities, Risk MAP will deliver quality data that increases public awareness and leads to action that reduces risk to life and property. 7

8 FEMA Risk MAP Discovery Levee projects will dominate funding in Arkansas in FY PAL expirations With and without levee analysis Determination of inundation area Other engineering needs All projects that are not levee or coastal Assessments and Risk MAP Products Review of all streams at a watershed level How are projects selected?

9 FEMA Risk MAP Discovery - Watersheds Step 1 Review of Trifecta Risk, Need and Elevation Watershed selection for Discovery (HUC-8) Step 2 Discovery Multiple meetings (up front coordination) Verification of CNMS data Local need collection Step 3 Decision Point Does the watershed require study? Review of Connectivity PROGRAM PLANNING DISCOVERY PROJECT? OR NO PROJECT?

10 FEMA Risk MAP Discovery Risk Average Annualized Loss Need Coordinated Needs Management Strategy Critical Elements Secondary Elements Major Change in Gage Record Rural regression equations in urban area Significant Change in Discharge Repetitive loss outside the SFHA Model Methodology not appropriate 50% Increase in Impervious Area Major Flood Control Structure >1 and <5 new/removed structures Channel outside SFHA Channel/shoreline improvements >5 new or removed hydraulic structures Land Use Change since effective Channel area change (scour) Failure to identify primary frontal dune High Water Mark data not included Availability of better topographic data Release of updated regression equations Elevation Adequate Coverage? Levees PAL expirations/needs funded separately

11 FEMA Risk MAP Discovery Study Decision Point

12 FEMA Risk MAP Discovery Study Decision Point Watershed Business Rules Risk (AAL) High Medium Low High Must Study Must Study Optional Need (CNMS) Medium Must Study Encouraged Optional Low Optional Optional Optional

13 FEMA Risk MAP Discovery Outreach: Kick-off Meeting If review of watershed indicates a project is essential Resulting scope will be relayed to all for input Once FEMA has decided were to invest, all communities will be contacted: Some watersheds will be studied Some will not be studied Region VI will hold Kick Off Meetings Intent is to ensure all communities know final scope for Mapping and Assessment Project

14 Study Discussion Discovery and Project Planning Grant County Watersheds 14

15 Study Discussion Discovery and Project Planning CNMS Validation Status 15

16 Study Discussion Discovery and Project Planning Upper Saline Watershed Covers approximately 90% of Grant County Contains the 5 incorporated areas within Grant County City of Sheridan Town of Leola Town of Tull Town of Poyen Town of Prattsville 16

17 Study Discussion Discovery and Project Planning Lower Arkansas - Maumelle Watershed Watershed based Project Planning for FY10 Discovery, Project Planning, and Prioritization will be completed Review of risk, need, elevation availability, and partner contribution Identify areas for study Engineering analysis will not be completed for this watershed under this SOP Contacted Counties Saline, Lonoke, Jefferson, Faulkner, Perry, Grant, and Pulaski, AR. Dependent on impact and extent of flooding 17

18 Study Discussion Community Needs Captured Initial Coordination Meeting was held on October 29, 2009 Captured Needs from the Community during the Meeting The communities indicated that corporate limits on the effective FIRM are incorrect Interest in detailed study within and just outside of the City of Sheridan due to development in the area Town Branch SFHA does not reflect detention basin Determined need to acquire improved terrain (LiDAR) data All community requests have been captured via the Coordination Needs Management Strategy (CNMS) 18

19 Study Discussion Terrain Data Light Detection And Ranging (LiDAR) Data What is LiDAR Description LiDAR is a remote sensing measuring system. Using the same principle as RADAR, it detects and locates distant objects by using a laser to shoot out a pulse of light then detects the pulse once it bounces back from a surface, and measures how long this process takes. Why is it important? LiDAR can make extremely accurate recordings from an aircraft. LiDAR data generates more accurate and detailed floodplains for insurance and floodplain management purposes. 19

20 Study Discussion Terrain Data Light Detection And Ranging (LiDAR) Data 20

21 Study Discussion Terrain Data Collected Data Terrain Information LiDAR acquisition Flown by Fugro EarthData in March 2010 Covers approximately 646 square miles LiDAR processing The county data was processed to LiDAR Class 1 (unclassified) A 25 square mile Area of Interest (AOI) covered the City of Sheridan and was created using a more detailed LAS Class 2 LiDAR data (bare earth) 2 foot contour equivalent vertical accuracy 21

22 Study Discussion Terrain Data Terrain Developed Area of Interest (AOI) 22

23 Study Discussion Terrain Data Terrain Developed Terrain (Topographic) Information Deliverables Final terrain data in File geodatabase (FGDB) format Point feature classes used to build DTM Clipping polygon used to define extents of DTM LiDAR LAS files All returns LiDAR Tile Index Spatial File XML metadata file Data Evaluation Tested vertically using NDEP and ASPRS procedures to ensure the data meets the project specifications. Completed October

24 Study Discussion Future Steps Upcoming Activities LiDAR data will be available to the County and Public Move towards getting the Upper Saline Watershed studied. This will cover Grant County AR. Estimated start time FY 11 or FY 12 24

25 Information Resources

26 Information Resources 26 26

27 Information Resources 27 27

28 Presentation Review Introduction FEMA Risk MAP Update Study Discussion Future Steps Questions 28

29 Contact Information - Arkansas Study Manger Contact Debasri Mitra dmitra@dewberry.com FEMA Project Monitor Guy Lowes guy.lowes@dhs.gov Arkansas NFIP Coordinator Michael Borengasser Arkansas Planning Contact Terry Gray, SHMO FEMA Mitigation Planning Contact Patricia Schaffer

30 Questions? 30

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