1. 14-April Univ of Delaware Philadelphia Engineer District 1 Delmarva Hurricane Evacuation Study (HES) Jason F. Miller, P.E. U.S. Army Corps of Engineers, Philadelphia District

2. 14-April Univ of Delaware Philadelphia Engineer District 2 The Basics What is a Hurricane? A hurricane is a type of tropical cyclone, which is a generic term for a low pressure system that generally forms in the tropics. The cyclone is accompanied by thunderstorms and, in the Northern Hemisphere, counterclockwise circulation of winds near the earth's surface. Hurricanes are categorized according to the strength of their winds using the Saffir-Simpson Hurricane Scale. A Category 1 storm has the lowest wind speeds, while a Category 5 hurricane has the strongest. These are relative terms, because lower category storms can sometimes inflict greater damage than higher category storms, depending on where they strike and the particular hazards they bring. In fact, tropical storms can also produce significant damage and loss of life, mainly due to flooding.

3. 14-April Univ of Delaware Philadelphia Engineer District 3 The Basics (cont.) What is Storm Surge? Storm surge is the difference between the observed water level and the normal astronomical tide; generally brought about by a very large meteorological disturbance (hurricane). Wind is the primary cause of storm surge by inducing currents in the direction of the wind. Surface current in turn produces subsurface currents. When these currents meet the sloping continental shelf, the water level rises (surge). Slower moving hurricanes tend to create deeper subsurface currents, and therefore may create higher surges than fast moving systems.

4. 14-April Univ of Delaware Philadelphia Engineer District 4 HURRICANE EVACUATION STUDY To provide information to emergency management officials that will be useful in hurricane evacuation decision-making and implementation. Program Objective

5. 14-April Univ of Delaware Philadelphia Engineer District 5 HAZARDS ANALYSIS VULNERABILITY ANALYSIS BEHAVIORAL SURVEYS SHELTER STUDIES TRANSPORTATION ANALYSIS HES Components

6. 14-April Univ of Delaware Philadelphia Engineer District 6 QUANTIFY SURGE HEIGHTS FOR INTENSITIES AND TRACKS OF HURRICANES CONSIDERED TO HAVE A REASONABLE METEOROLOGICAL PROBABILITY OF OCCURRENCE WITH STUDY AREA TIDAL FLOODING SlightlyDatedPhoto HAZARDS

7. 14-April Univ of Delaware Philadelphia Engineer District 7 ASSESS POTENTIAL EFFECT OF INLAND (RAINFALL) FLOODING HAZARDS ON EVACUATIONS RIVERINE FLOODING HAZARDS

8. 14-April Univ of Delaware Philadelphia Engineer District 8 Sea, Lake and Overland Surges from Hurricanes

9. 14-April Univ of Delaware Philadelphia Engineer District 9 SLOSH Data MEOW Maximum Envelope Of Water: Based on hypothetical storm track and intensity MOM Maximum Of Maximums: Composite of MEOWs for each category storm

10. 14-April Univ of Delaware Philadelphia Engineer District 10 SLOSH MODEL CAT 3 MAXIMUM SURGE ELEVATIONS

11. 14-April Univ of Delaware Philadelphia Engineer District 11 DIGITAL ELEVATION MODEL (DEM)

12. 14-April Univ of Delaware Philadelphia Engineer District 12 Digital Elevation Model (ground elevations) Resultant Inundation Area Surge Height Grid Ground elevations subtracted from surge heights to determine areas Subject to flooding

13. 14-April Univ of Delaware Philadelphia Engineer District 13

14. 14-April Univ of Delaware Philadelphia Engineer District 14 IDENTIFY AREAS, POPULATIONS AND FACILITIES THAT ARE VULNERABLE TO HURRICANE SURGE AND WINDIDENTIFY AREAS, POPULATIONS AND FACILITIES THAT ARE VULNERABLE TO HURRICANE SURGE AND WIND VULNERABILITY ANALYSIS 1 ST STEP: INUNDATION MAPPING 2 ND STEP: ASSEMBLE CENSUS AND RELATED DATA AND ASSEMBLE HIGHWAY DATA AND ASSEMBLE HIGHWAY DATA

15. 14-April Univ of Delaware Philadelphia Engineer District 15 Vulnerability Zones

16. 14-April Univ of Delaware Philadelphia Engineer District 16

17. 14-April Univ of Delaware Philadelphia Engineer District 17 TRAFFIC ANALYSIS ZONES -Used to support traffic modeling EVACUATION ZONES - Used operationally by emergency management officials VULNERABILITYANALYSIS

18. 14-April Univ of Delaware Philadelphia Engineer District 18 Assumptions regarding public response - Percentage of the population that will evacuate under a range of hurricane scenarios and/or in response to evacuation advisories - Timing of public response - Number of vehicles that evacuees will use - Probable Destinations (shelter, with local friends, local hotel/motel, out-of-county, out-of-state) - Responses of tourists Behavioral Analysis –

19. 14-April Univ of Delaware Philadelphia Engineer District 19 I lived here for 35 years and…I lived here for 35 years and… I’ve really never thought about it.I’ve really never thought about it. What about my pets?What about my pets? A Category 1 isn’t too bad.A Category 1 isn’t too bad. I don’t live on the beach.I don’t live on the beach. I don’t have reliable transportationI don’t have reliable transportation BEHAVIORAL SURVEYS