Flood Map Revisions. Town of Nags Head Public Information and Input Session. December 14, 2016, 6 pm

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1 Flood Map Revisions Town of Nags Head Public Information and Input Session December 14, 2016, 6 pm

2 Flood Map Revisions New preliminary flood maps released for Dare County June 30, Last update September 20, 2006

3 Flood Map Revisions Flood Maps are issued by FEMA as part of National Flood Insurance Program (NFIP) Three main purposes of (NFIP): To make flood insurance available To identify floodplains and areas at risk of flooding To provide standards, guidance, and a framework to help communities manage floodplains

4 Flood Map Revisions Flood Insurance Rate Map (FIRM) A digitally-produced FIRM, whether viewed in hardcopy or in digital form All FIRMs produced by the North Carolina Floodplain Mapping Program are digital FIRMs Flood Insurance Study (FIS) Details the examination, evaluation, and determination of flood hazard areas FIRMs are part of the FIS Base Flood Elevation (BFE) In areas where these are established, this is the minimum elevation above mean sea level that the first floor (AE) or the bottom of lowest horizontal member (VE) of a structure must be elevated Special Flood Hazard Area (SFHA) The 1% annual chance floodplain, where NFIP regulations must be enforced by the community as a condition of participation in the NFIP

5 Flood Map Revisions Final Community Meetings January 10 th - Kill Devil Hills Town Hall January 11 th - Dare County Board of Commissioners Meeting Room, Manteo January 12 th - Fessenden Center, Buxton All meetings are from 5-7 pm

6 Flood Map Revisions months total Current maps are used for flood insurance and regulatory purposes until the new maps become effective

7 Flood Map Revisions Appeals An appeal is a formal objection to new or revised BFEs, SFHA and Floodway boundaries in the preliminary data that is submitted during the 90- day appeal period Appeals are based on data that show proposed BFEs to be scientifically or technically incorrect for Appeals and Comments fact sheet Planning and Development staff can assist with appeals

8 Flood Map Revisions Six month compliance period Starts after all appeals have been resolved Town adopts new flood damage prevention ordinance based on model guidance during this timeframe Town notifies by mail all property owners with map changes Process similar to zoning map amendment Considerations for BOC for new ordinance involve higher regulatory standards Communities can adopt regulations above minimum requirements Nags Head currently has higher regulatory standards for freeboard, enclosures below BFE, substantial improvements

9 Flood Map Revisions New mapping process New storm surge analysis was used (last surge model update was in 1981) Advances in wave analyses and coastal surge modeling methods New and more accurate data (LIDAR and FFE) Reflect surge events since 1980 (Emily, Fran, Isabel, Ophelia) Tighter transects, more detailed data and analyses

10 Flood Map Revisions Nags Head Flood Zones VE Velocity zone, impacts from stillwater base flood elevation + 3 waves AE impacts from stillwater base flood elevation only 1% annual chance flooding (100 year storm) VE and AE zones have established BFE s, minimum elevations above sea level required for construction AO areas of shallow flooding associated with low lying topography, no BFE, minimum elevation is required above highest adjacent grade X Non-regulatory flood zone, no insurance or construction requirements, still subject to 0.2% annual chance of flooding

11 Flood Map Revisions Changes with new preliminary maps Primary frontal dune has been established and used in modeling of storm surge Reducing in surge impacts, overland waves, and stillwater elevations Fewer VE zone properties Fewer AE zone properties, particularly west of NC 12 Removal of causeway properties from VE zone Base flood elevations reduced in AE zone; most new BFE s are 4 or 5, formerly Addition of AO zones west of primary frontal dune

12 Flood Map Revisions V-Zone A-Zone Current Updated Current Updated Nags Head 1, , *Some V zone properties will be included in AO Zones

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20 Soundside Road/Southridge

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22 Constructed No flooding Middle house did not have damage; adjacent homes flooded 1 ft. in ground floor All in current AE zone All proposed to be removed from flood zone (no BFE)

23 Old Nags Head Cove

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25 Constructed Current- AE Proposed- Removed

26 Lakeside

27 Homes outside proposed flood zone; grade elevations between four and five feet; 3-4 water noted in building

28 Pond Island

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30 Constructed Current- VE Proposed- Removed No damage in Irene Only house on East Shore Road and North Shore Road that did not flood during Hurricane Irene. House elevated above adjacent grades with clear space underneath.

31 Constructed Current- VE Proposed- removed Experienced 2ft of damage during Hurricane Irene. New homes could be built at-grade; elevation below 4

32 South Nags Head

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36 Constructed 1955 Current- AE Flood Zone Proposed Mapsnot in flood zone Received 2 feet of flooding during Hurricane Irene

37 Constructed 2004 Current- AE 1.5 feet damage from flooding Constructed 1983 Current- AE No damage from flooding Lots across the street (at the same elevation) which also had 1.5 feet of damage have been removed from the flood zone

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39 Hurricane Matthew

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47 Field Work Findings Elevated lots had less damage compared to houses of the same structure on lower elevations in the same neighborhood Ground level houses had significant damage Newer structures appear to have less damage in general Reaffirm concerns shown on maps; slight differences in elevation = changes risk significantly

48 Discussion New base flood elevations of four feet appear to be insufficient to protect from storm similar to Irene Flood zone boundaries do not capture all structures that were flooded during Irene Properties not in new flood zone or with ground elevations above 4 (5 in Nags Head) could be built at-grade with heated space (most damage during Irene was caused just to ground floor enclosures.) Considerations?? request more detailed study to include Irene and shallow flooding events; file formal appeal

49 Flood Map Revisions Staff Contacts: Chief Building Inspector/Floodplain Administrator David Morton; ( ) or Senior Building Inspector Steve Szymanski; ( ) or Principal Planner Holly White; ( ) or Deputy Town Manager Andy Garman; ( ) or

50 Flood Map Revisions Questions/Comments?