FHWA National Bridge Inventory

Use in your agent

Load 2026 District of Columbia bridge data into Parquet. Checked against the provider's documentation on Nov 1, 2026.

Access

• No account or key. FHWA publishes state-level Excel, JSON and GeoJSON files plus nationwide downloads.
• This bounded example uses the District of Columbia JSON file rather than the 624,939-record nationwide file.

Request

curl -O 'https://www.fhwa.dot.gov/bridge/nbi/2026/JSON/DC26.json'

Format

JSON array with one object per bridge. Top-level SNBI codes cover identity, location, geometry, condition, inspection and rating data, while some fields contain nested feature and route arrays.

Load into pandas and Parquet

Needs Python 3 with requests, pandas and pyarrow.

"""FHWA 2026 District of Columbia NBI JSON -> pandas -> Parquet."""
import requests
import pandas as pd

URL = "https://www.fhwa.dot.gov/bridge/nbi/2026/JSON/DC26.json"
r = requests.get(URL, timeout=60)
r.raise_for_status()
df = pd.DataFrame(r.json())
df.to_parquet("fhwa_nbi_dc_2026.parquet", index=False)
print(len(df), "bridges", "columns", len(df.columns),
      "named", int(df["BID02"].notna().sum()))

Run by us on 2026-11-01 (python 3.13.5 | pandas 3.1.0 | pyarrow 26.0.0 | requests 2.34.2). Result: 261 bridges columns 79 named 261

Limits

• Download rate limit: Not stated.
• The checked 2026 release contains 624,939 public highway bridges nationwide.
• The executed example is one jurisdiction and is not a nationwide extract.

Quirks

• SNBI field names are compact codes such as BID02 and BC01; retain the applicable SNBI specification and schema with each release.
• Features and routes are nested arrays, so normalize them into child tables when route-level analysis is needed.
• The 2026-2027 transition can introduce temporary codes and null values.
• Use inventory year and inspection dates explicitly; the publication date is not the inspection date.

Terms and attribution

• FHWA publishes the files for public download without an account or key.
• The NBI page says not to use the data for route clearance.
• No separate uniform data licence was stated on the checked NBI pages.

Sources

• https://www.fhwa.dot.gov/bridge/nbi/nbi_data.cfm: “may be corrected or updated throughout the year.”
• https://www.fhwa.dot.gov/bridge/nbi/nbi_data.cfm: “In general, bridges are inspected every 24 months”
• https://www.fhwa.dot.gov/bridge/nbi/nbi_data_2026.cfm: “Download All Highway Bridges 2026 NBI Data in JSON format”