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For visual damage assessments using post-event imagery:
Destroyed structures are classified based on a visual post-event imagery review that the structure was collapsed. Affected structures were classified based on a visual post-event imagery review indicating there were missing roof segments, failure of structural elements, and visible damage. Visual imagery assessments are primarily completed using nadir “looking straight down” imagery so damages to the sides of buildings were not included in the visual assessments. Often, imagery was not acquired during peak flood crests on rivers or surge inundation along the coast and as a result, the visual assessments may focus on resulting wind damages, not flood impacts. There may be damages visible on-the-ground that were not assessed using the imagery.
For modeled damage assessments using depth grids:
Damage categories (Affected, Minor, Major, Destroyed) are derived from flood depths at the structure as characterized by the best-available flood depth grid at the time of the damage assessment.
Data DictionaryDamage Level:
The damage category assigned to the structure based on modeled or visual assessment.
No Damage
Affected
Minor
Major
Destroyed
Damage Type:
The type of event that created the damage. Multi-event: more than one type of event created damage.
Assessment Type:
The method for assigning a damage category:
Field Assessed: damage category validated in the field
Modeled: damage category predicted based on modeled wind, flood or surge data
Other type: damage category predicted based on other type of geospatial analysis
Remote Sensing: damage category assigned using image processing and image validation
Unknown: damage category predicted based on unknown type of analysis
Inundation Depth:
Depth of flooding in feet. Predicted/modeled or measured/observed.
Wind Exposure Level:
Severity of wind impact the structure experienced based on the Saffir-Simpson Hurricane Wind Scale or the Enhanced Fujita Rating for Tornados.
Peak Ground Acceleration:
PGA experienced by the structure during an earthquake based on USGS ShakeMap GIS data.
Accessible:
Indicates whether the structure is accessible or inaccessible due to debris, flooding, damage or other reason.
Production Date:
Date when the damage category was assigned.
Imagery Date:
Acquisition date of the image that was used to assign structural damage categories.
Event Name:
Name of the natural disaster that caused the damage.
Event Date:
The date of the event or natural disaster.
Data Producer:
Organization that created the damage assessment data.
Disaster Number:
Unique ID value assigned for natural disaster events.
USNG:
The USNG grid ID that the structural damage lies within.
Public: This dataset is intended for public access and use.