GIS 5100 - Damage Assessment

 As a follow up to the last module on Coastal Flooding, this module focuses on the damage assessment after a coastal flooding event, such as a hurricane and it's associated storm surge. In 2012 hurricane Sandy impacted the north eastern coast of the US and left behind monumental damage. This week's module tasked students with performing their own analysis of a portion of the area impacted by hurricane Sandy. In the first instance we were required to create a map of hurricane Sandy's track. The following is my result: 


We were then asked to mosaic imagery of the New Jersey shoreline pre hurricane Sandy and post hurricane Sandy, followed by doing a comparative desktop study to assess the damage caused by the storm. To assess the damage a point was created for each building in the study area and the structure damage, wind damage and inundation was determined and ranked based on FEMA standards. The following is an image of the building points based on structural damage: 


To further analyze the structural damage, we then determined the amount of damage within 100m of the coastline, within 100m to 200m of the coastline and within 200 to 300m of the coastline. To do this I chose to perform the following steps:

  1. Create a buffer layer of the coastline at 100m, 200m and 300m. 
  2. Create a layer that includes damage assessment points intersecting the 100m, 200m and 300m buffers. 
  3. Use the erase tool to eliminate damage assessment points from the 200m feature class that were less than 100m. 
  4. Use the erase tool to eliminate damage assessment points from the 300m feature class that were less than 200m. 
  5. Select by attribute the buildings that were at each of the various damage levels from each of the 3 created feature classes representative of each zone (0-100m, 100m-200m, 200m-300m)

My analysis determined that: 

Structure Damage Category

Count of Structures

0-100 m from coastline

Percentage

Count of Structures

100-200 m from coastline

Percentage

Count of Structures

200-300 m from coastline

Percentage

No Damage

0

0%

0

0%

10

22%

Affected

0

0%

7

18%

19

42%

Minor Damage

0

0%

12

30%

11

25%

Major Damage

2

17%

16

40%

5

11%

Destroyed

10

83%

5

12%

0

0%

Totals

12

100%

40

100%

45

100%


  


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