Direct Structure Losses

The direct economic losses to structures are provided through a few packages and can be computed via the national structure inventory or alternatively provided sources. The direct economic losses are based on a computation of damage through the assigned damage functions for an occupancy type. Each structure is assigned an occupancy type with a family of damage relationships that are grouped by hazard type. For instance an occupancy type may have a damage function for depth, depth and velocity, wave height salinity and depth or other hazard types.

The base computation is stored in the structures.structure.go file. The computation first checks if the depth parameter is available on the hazard type because all damage functions are ultimately based on a depth percent damage currently. If depth is present, the foundation height of the structure is subtracted from the depth to create depth above finished floor elevation. The proper damage function is queried from the damage function family for contents and structures, the resulting damage percentage value is converted from a percent to a decimal by dividing by 100 and then is applied to structure and content values accordingly.

The current result is provided with the following output fields:

parameter name	type	description
"fd_id"	string	unique structure identifier
"x"	float64	x coordinate
"y"	float64	y coordinate
"hazard"	complex type	a json representation of the hazard type
"damage category"	string	damage category name
"occupancy type"	string	occupancy type name
"structure damage"	float64	damage to the structure in dollars
"content damage"	float64	damage to the contents in dollars
"pop2amu65"	int	population night under 65 years old
"pop2amo65"	int	population night over 65 years old
"pop2pmu65"	int	population day under 65 years old
"pop2pmo65"	int	population day over 65 years old

Structure Inventory Sources

Structure inventories are provided through the consequences.StreamProcessor interface, currently there are three ways to provide structure data to the go-consequences compute engine.

1. From the NSI directly
2. From GeoPackage
3. From Shapefile

If you use the NSI directly, you must have access to the NSI api service which is behind the USACE firewall. It also requires a valid internet connection.

For the other two data sources the data must be in a standardized schema. This allows the user to provide their own structure inventory, but it requires the database meet schema specifications. The required fields are:

• "fd_id" (integer) this is used as a name
• "cbfips" (string) the census block fips code
• "x" (64 bit float/Real) the x value in 4326
• "y" (64 bit float/Real) the x value in 4326
• "st_damcat" (string) the damage category, {“Res”, “Com”, “Ind”, “Pub”} – can be used for aggregation of results.
• "occtype" (string) the occupancy type, used for setting damage function selection. Options are listed below.
• "val_struct" (64 bit float/Real) the structure value in dollars
• "val_cont" (64 bit float/Real) the content value in dollars
• "found_ht" (64 bit float/Real) the height of the foundation above ground elevation.
• "found_type" (string) the foundation type. (PIER, PILE, UNATTACHED, BASEMENT, SLAB)

Occupancy Types:

• "AGR1"
• “COM1”
• "COM2"
• "COM3"
• "COM4"
• "COM5"
• "COM6"
• "COM7"
• "COM8"
• "COM9"
• "COM10"
• "EDU1"
• "EDU2"
• "GOV1"
• "GOV2"
• "IND1"
• "IND2"
• "IND3"
• "IND4"
• "IND5"
• "IND6"
• "REL1"
• "RES1-1SNB"
• "RES1-1SWB"
• "RES1-2SNB"
• "RES1-2SWB"
• "RES1-3SNB"
• "RES1-3SWB"
• "RES1-SLNB"
• "RES1-SLWB"
• "RES2"
• "RES3A"
• "RES3B"
• "RES3C"
• "RES3D"
• "RES3E"
• "RES3F"
• "RES4"
• "RES5"
• "RES6"