Vital Signs: Bridge Condition – Bay Area (2022)

VITAL SIGNS INDICATOR

Bridge Condition (T18)

FULL MEASURE NAME

Structurally deficient share of bridge deck area

LAST UPDATED

January 2023

DESCRIPTION

Bridge condition here is measured by the share of bridge and overpass deck area rated as “Poor” according to the FHWA’s National Bridge Inventory (NBI) condition ratings, which account for ratings of the bridge’s deck, superstructure, substructure, or culvert.

DATA SOURCE

Federal Highway Administration: National Bridge Inventory - http://www.fhwa.dot.gov/bridge/nbi.cfm

1992-2022

CONTACT INFORMATION

vitalsigns.info@mtc.ca.gov

METHODOLOGY NOTES (across all datasets for this indicator)

Bridge deck area rating definitions (Good, Fair, Poor) are from the FHWA Bridge Inventory - https://www.fhwa.dot.gov/bridge/britab.cfm. Regional performance was examined by summing all of the bridge deck area by rating and dividing it by total bridge deck area. Individual bridges reports 2022 data for bridges within the nine-county Bay Area. For metro comparisons, the Bay Area uses the nine-county region instead of separate metropolitan statistical areas (MSAs). Note that metro comparisons use current MSA boundaries for historical data. In 2018, the FHWA updated its bridge condition metrics, deprecating the terms “Structurally Deficient” and “Structurally Sound” in favor of as "Good", "Fair" and "Poor", which are used in this Vital Signs indicator for current and historical data.

Querying over HTTP

Splitgraph serves as an HTTP API that lets you run SQL queries directly on this data to power Web applications. For example:

curl https://data.splitgraph.com/sql/query/ddn \
    -H "Content-Type: application/json" \
    -d@-<<EOF
{"sql": "
    SELECT *
    FROM \"bayareametro-gov/vital-signs-bridge-condition-bay-area-2022-dd8w-7y7p\".\"vital_signs_bridge_condition_bay_area_2022\"
    LIMIT 100 
"}
EOF

See the Splitgraph documentation for more information.