Beach Nourishment Project Town of Kitty Hawk, North Carolina

1. Beach Nourishment Project Town of Kitty Hawk, North Carolina Coastal Planning & Engineering of North Carolina November 3, 2014 Ken Willson

2. Project Overview Map

3. Kitty Hawk Project Area

4. Kitty Hawk Stated Purpose: • Reduce the vulnerability of public infrastructure including NC 12, town roads between NC 12 and U.S. Highway 158, and utilities to storm-induced erosion; • Reduce flooding experienced in many non-oceanfront areas throughout the Town during ocean over wash conditions, including portions of NC Highway 12 and U.S. Highway 158; and • Reduce the vulnerability of homes within the Town that front the Atlantic Ocean and are exposed to wave events during nor’easters and other large storm events as well as natural trends.

5. Storm Damage Reduction to Infrastructure

6. Flood Damage Reduction to Non-Oceanfront Areas

7. Storm Damage Reduction to Oceanfront Homes

8. Storm Damage Reduction Project

9. Storm Damage Reduction Project Example Berm Width 6.0 ft. NAVD88 Dune Design Beach

10. Storm Damage Reduction Project Example Constructed Beach Fill

11. Post-Construction Adjustment in 1-3 years Storm Damage Reduction Project Example

12. Storm Damage Reduction Project Example Advance Fill Design Beach

13. Storm Damage Reduction Project Example Berm Width 6.0 ft. NAVD88 Dune Loss of Advance Fill In 5-10 years Design Beach

15. Storm Damage Reduction Project Example • When structures are seaward of the dune, more sand is required to • construct the design seaward of the structures.

16. Storm Damage Reduction Project Example Built in front of structures Berm Width 6.0 ft. NAVD88 Dune +13.0 ft. Design Beach • When structures are seaward of the dune, more sand is required to • construct the design seaward of the structures.

17. Storm Damage Reduction Project Example Tie into existing dune Berm Width 6.0 ft. NAVD88 Dune +13.0 ft. Design Beach • When structures are seaward of the dune, more sand is required to • construct the design seaward of the structures.

18. 81% Increase

19. Berm Only Option 50’ Berm Width 6.0 ft. NAVD88 Design Beach

20. Minimal Dune Design - 12 30’ Berm Width 6.0 ft. NAVD88 10’ Dune Width +12.0 ft. Design Beach

21. Storm Damage Reduction Analysis • Reduce the vulnerability of public infrastructure including NC 12, town roads between NC 12 and U.S. Highway 158, and utilities to storm-induced erosion; • Minimal simulated impact to the road given existing conditions • No impacts to the road with berm only or MDD-12 design. • Reduce the vulnerability of homes within the Town that front the Atlantic Ocean and are exposed to wave events during nor’easters and other large storm events as well as natural trends; • 122 structures impacted given existing conditions. 48% reduction with berm only and 64% reduction with MDD-12 design

22. Runup Evaluation Calculated Runup Elevation

23. Runup Evaluation Calculated Runup Elevation

24. Runup Evaluation Runup Elevation

25. Runup Evaluation Calculated Runup Elevation Without Project With Project Design Beach Design Beach

26. Runup Evaluation Calculated Runup Elevation Without Project With Project Design Beach Design Beach Design Beach Design Beach

27. Runup Evaluation Calculated Runup Elevation Without Project With Project Design Beach Design Beach Design Beach Design Beach

28. Runup Evaluation Runup Elevation = Lower Than Elevation of the Road

29. Annual Event Runup Analysis • 12 ft. Dune Design and 50 Ft. Berm: • 69.8% to 92.7 % reduction in length of shoreline exceeded by calculated runup.

30. 5 – Year Event • “Kill Devil Hills” Design – 15 ft. high / 20 ft. wide dune, fronted by a 40 ft. berm • Advances Shoreline 100 ft. (Average) • Requires 3.19 Million CY • 100% increase in Volume • Additional $15 Million • 100 – Ft. Berm Only Design • Advances Shoreline 100 ft. • Requires 2.93 Million CY • 84% increase in Volume • Additional $12.5 Million • What could we do with another $2 Million - $3 Million

31. 5 – Year Event • $ 3 Million = ~ 16 CY/Ft. More Sand • Design: Slightly Over a 60 ft. Design Berm • Annual Event - 73.4% to 98.7 % reduction in length of shoreline exceeded by calculated runup. • 5-Year Event – 39.6% to 72.2% reduction in length of shoreline exceeded by calculated runup.

32. Runup Evaluation Runup Elevation

33. 5 – Year Event • $ 3 Million = ~ 16 CY/Ft. More Sand • Design: Slightly Over a 60 ft. Design Berm • Annual Event - 73.4% to 98.7 % reduction in length of shoreline exceeded by calculated runup. • 5-Year Event – 39.6% to 72.2% reduction in length of shoreline exceeded by calculated runup. • With 14.0 ft. NAVD Starter Dune these numbers become 100%

34. 60 Ft. Berm Design • 60 Ft. Berm; 14.0 ft. NAVD “Starter Dune”; Sand Fencing • Main Fill Length – 18,900 ft. (3.58 miles) • 1000 Ft. Taper on North End • Fill Density ~ 95 cy/ft. to ~100 cy/ft. • Total Volume = ~1.91 Million Cubic Yards • Project Cost = ~$20.5 Million

35. Schedule

36. Beach Nourishment Project Town of Kitty Hawk, North Carolina Questions?? Ken Willson – Kenneth.Willson@cbi.com

37. Kill Devil Hills Project Area

38. Duck Project Area