README for “National Bridge Inventory (NBI) 2008-Present” dataset. U.S. Department of Transportation (DOT), Federal Highway Administration (FHWA); U.S. Department of Transportation (USDOT), Bureau of Transportation Statistics (BTS) [distributor] 2025-05-29 ---------------------------------------------------------------- LINKS TO DATASET ---------------------------------------------------------------- A. Dataset archive link: https://doi.org/10.21949/1520766 B. NTAD catalog dataset link (Current Year): https://doi.org/10.21949/1522152 ---------------------------------------------------------------- SUMMARY OF DATASET ---------------------------------------------------------------- The National Bridge Inventory (NBI) 2008-Present dataset is from the Federal Highway Administration (FHWA), and is part of the U.S. Department of Transportation (USDOT)/Bureau of Transportation Statistics’s (BTS's) National Transportation Atlas Database (NTAD). The data describes more than 615,000 of the Nation's bridges located on public roads, including Interstate Highways, U.S. highways, State and county roads, as well as publicly-accessible bridges on Federal and Tribal lands. The inventory data present a complete picture of the location, description, classification, and general condition data for each bridge. The element data present a breakdown of the condition of each structural and bridge management element for each bridge on the National Highway System (NHS). The Recording and Coding Guide for the Structure Inventory and Appraisal of the Nation's Bridges contains a detailed description of each data element including coding instructions and attribute definitions. The Coding Guide is available at: https://doi.org/10.21949/1519105. ---------------------------------------------------------------- TABLE OF CONTENTS ---------------------------------------------------------------- A. General Information B. Sharing/Access & Policies Information C. Data and Related File Overview D. Methodological Information E. Data-Specific Information for: National Bridge Inventory (NBI) 2008-Present [datasets] F. Update Log ---------------------------------------------------------------- A. GENERAL INFORMATION ---------------------------------------------------------------- 0. Title of Dataset: National Bridge Inventory (NBI) 2008-Present [dataset] 1. Description of Dataset: The National Bridge Inventory (NBI) 2008-Present dataset is from the Federal Highway Administration (FHWA), and is part of the U.S. Department of Transportation (USDOT)/Bureau of Transportation Statistics’ (BTS's) National Transportation Atlas Database (NTAD). The data describes more than 615,000 of the Nation's bridges located on public roads, including Interstate Highways, U.S. highways, State and county roads, as well as publicly-accessible bridges on Federal and Tribal lands. The inventory data present a complete picture of the location, description, classification, and general condition data for each bridge. The element data present a breakdown of the condition of each structural and bridge management element for each bridge on the National Highway System (NHS). The Recording and Coding Guide for the Structure Inventory and Appraisal of the Nation's Bridges contains a detailed description of each data element including coding instructions and attribute definitions. The Coding Guide is available at: https://doi.org/10.21949/1519105. 2. Dataset archive link: https://doi.org/10.21949/1520766 3. Authorship Information: Principal Data Creator or Data Manager Contact Information Institution: U.S. Department of Transportation (DOT), Federal Highway Administration (FHWA) Address: 1200 New Jersey Ave SE, Washington D.C. 20590 Contact: ExecSecretariat.FHWA@dot.gov Data Distributor Contact Information Name: National Transportation Atlas Database (NTAD) Institution: U.S. Department of Transportation (USDOT), Bureau of Transportation Statistics (BTS), Office of Spatial Analysis and Visualization (OSAV) Address: 1200 New Jersey Ave. SE, Washington D.C. 20590 Email: ntad@dot.gov 4. Date of data collection and update interval: This dataset is updated annually. 5. Geographic location of data collection: United States of America 6. Information about funding sources that supported the collection of the data: Federal Highway Administration (FHWA), U.S. Department of Transportation (DOT) ---------------------------------------------------------------- B. SHARING/ACCESS & POLICIES INFORMATION ---------------------------------------------------------------- 0. Recommended citation for the data: U.S. Department of Transportation (DOT), Federal Highway Administration (FHWA), U.S. Department of Transportation, Bureau of Transportation Statistics (BTS) [distributor]. National Bridge Inventory (NBI) 2008-Present [datasets]. https://doi.org/10.21949/1520766 1. Licenses/restrictions placed on the data: These data are in the Public Domain. 2. Was data derived from another source?: Yes. 23 CFR 650 Subpart C (National Bridge Inspection Standards) requires that States, federal agencies, and tribal governments maintain an inventory of all public highway bridges within their jurisdiction, and submit that data to the Federal Highway Administration (FHWA) annually or as requested. Bridges that are not federally or tribally owned (i.e. local or privately owned bridges) are submitted by the State. Regulation requires data to be submitted March 15th of each year, though there may be updates throughout the year. 3.This document was created to meet the requirements enumerated in the U.S. Department of Transportation's 'Plan to Increase Public Access to the Results of Federally-Funded Scientific Research' Version 1.1 << https://doi.org/10.21949/1520559 >> and guidelines suggested by the DOT Public Access website << https://doi.org/10.21949/1503647 >>, in effect and current as of December 03, 2020. ---------------------------------------------------------------- C. DATA & RELATED FILE OVERVIEW ---------------------------------------------------------------- 1. File List for the National Bridge Inventory (NBI) 2008-Present dataset A. Filename: National_Bridge_Inventory_NTAD2008_Present.zip Short description: Compressed file folders containing the geospatial data for National Bridge Inventory (NBI) 2008-Present dataset. File folders are classified by NTAD publication year and data vintage year or date respectively. B. Filename: bts_NTAD_NBI_DMP_20250529.pdf Short description: A PDF file containing the Data Management Plan that was created for current and future management of the data and associated files. C. Filename: bts_NTAD_NBI_README_20250529.txt Short description: The README.txt file that includes human-readable information about the data, variable definitions, contact information, and other contextual information. The file you are reading now. 2. File List for the NBI_NTAD2008_Present.zip collection. A. Filename: NTADXXXX_SHP_Final_NBI*.zip or NTADXXXX_GDB_Final_NBIXXXX_XXXX_XX_XX.zip Short description: Compressed file folders containing the geospatial data for National Bridge Inventory (NBI) 2008-Present dataset. File folders are classified by NTAD publication year, data year, and data vintage date respectively. 3a. File List for the NTADXXXX_SHP_Final_NBI*.zip collection. A. Filename: nbi.shp Short description: A shapefile containing the geospatial data for National Bridge Inventory (NBI) 2008-Present dataset. This includes associated files with extensions .prj, .dbf, .sbn, .sbx, .shx. B. Filename: nbi.txt, nbi.htm, and nbi.shp.xml Short description: Text files containing key metadata and documentation information such as methodology, procedures, data dictionary, etc. C. Filename: mtguide.pdf or nbi_coding_guide.pdf Short description: A pdf document detailing attribute and encoding information for National Bridge Inventory (NBI) 2008-Present dataset. 3b. File List for the NTADXXXX_GDB_Final_NBIXXXX_XXXX_XX_XX.zip collection A. Filename: NTADXXXX_GDB_Final_NBIXXXX_XXXX_XX_XX.gdb.zip Short description: A file geodatabase containing the geospatial data for National Bridge Inventory (NBI) 2008-Present dataset. Geodatabase (GDB) folders contain all the necessary components to view and otherwise interact with their data. B. Filename: National_Bridge_Inventory.xml and National_Bridge_Inventory_Elements.xml Short description: Text files containing key metadata and documentation information such as methodology, procedures, etc. C. Filename: NBI.xlsx and NBI_Element.xlsx, or National_Bridge_Inventory.xlsx and National_Bridge_Inventory_Element_Data.xlsx Short description: Excel spreadsheet containing the dataset's data dictionary. D. Filename: coding_guide_nbi_dec1995.pdf Short description: A pdf document detailing attribute and encoding information for National Bridge Inventory (NBI) 2008-Present dataset. ---------------------------------------------------------------- D. METHODOLOGICAL INFORMATION ---------------------------------------------------------------- 1. Description of methods used for collection/generation of data: 23 CFR 650 Subpart C (National Bridge Inspection Standards) requires that States, federal agencies, and tribal governments maintain an inventory of all public highway bridges within their jurisdiction, and submit that data to the Federal Highway Administration (FHWA) annually or as requested. Bridges that are not federally or tribally owned (i.e. local or privately owned bridges) are submitted by the State. Regulation requires data to be submitted March 15th of each year, though there may be updates throughout the year. The dataset is archived on December 31st and typically published in January. 2. Instrument- or software-specific information needed to interpret the data: The data and documentation files can be opened with Esri ArcMap and any GIS software package. ---------------------------------------------------------------- E. DATA-SPECIFIC INFORMATION ---------------------------------------------------------------- 1. National Bridge Inventory (NBI) data table This dataset is updated annually. Dataset Manager is contacted to verify changes to data resulting in NTAD update. The metadata is updated in the same manner. For the most recent data, please visit the NTAD catalog at https://doi.org/10.21949/1522152 A. Number of variables (columns): The data dictionary found in (PDF documentation) provides definitions for the variables B. Data Dictionary/Variable List: Because of the large number of variables, please refer to the Data Dictionary found within the file NBI.txt for names, definitions, and formats of variables. C. Missing data codes: None ---------------------------------------------------------------- F. UPDATE LOG ---------------------------------------------------------------- This bts_NBI_20250529_README.txt file was originally created on 2021-02-09 by Dominic Menegus, Geographer, dominic.menegus@dot.gov [Note changes or update to the readme.txt file, e.g.:] 2021-02-09: Original file created 2025-05-29: Revised document, including data descriptions and file organization.