National Cross-Section Database (NXSDB), Water Year 2023 (schema version 1.2.0, September 2025)

This data release presents a national cross-section (XS) database (NXSDB) of bathymetric cross-sections collected during water year (WY) 2023 (October 1, 2022, to September 30, 2023). The WY 2023 NXSDB has been approved by the U.S. Geological Survey (USGS) for publication and supersedes the provisional version. The data were collected by hydrographers during routine site visits to thousands of USGS streamgaging stations for river discharge measurements. The database comprises approximately 64,500 individual cross-sections from 8,556 stations across the United States and is provided as an Open Geospatial Consortium (OGC) GeoPackage file named NXSDB_WY2023_CONUS.gpkg.

A rendered HTML README documentation file (README_Documentation.html) accompanies the release and provides essential context for data users, including information on the database’s development, structure, processing assumptions, and data inclusion criteria. The cross-section data have undergone automated quality checks to identify missing values, structural inconsistencies, and extreme outliers. However, unlike finalized discharge measurements published in the National Water Information System (NWIS), these data have not received the same level of manual review. Although approved for release by the USGS, no expressed or implied warranty is made regarding their use, display, or suitability for other systems or for general or scientific applications. Users are encouraged to consult the accompanying README to understand the quality control procedures and data cleaning methods applied prior to database integration, as well as the assumptions involved. This understanding is essential for appropriately interpreting the data and assessing its suitability for specific analytical purposes.

The README also describes the naming conventions used in the WY 2023 database, which is organized into table layers within the GeoPackage. The file contains three main types of layers. The "geometry" layer is the only one that includes geospatial information and contains georeferenced and hydrographically addressed points representing station locations, along with summary information on the total number of cross-section measurements. Each station has a corresponding "record" layer that summarizes the available cross-section measurements. The third main layer type is the "measurement" layer, which represents individual cross-sections. This layer has two subtypes corresponding to the primary methodologies used to collect discharge measurements: midsection-method measurements, which are not georeferenced, and moving-boat acoustic Doppler current profiler (ADCP) measurements, which are sometimes georeferenced with real-world spatial coordinates (latitude and longitude).

Due to the size of the database, programmatic access is recommended for efficient querying and analysis. To support users, demonstration packages in both R and Python are included in demo.zip. These packages contain custom functions designed to simplify interaction with the GeoPackage, since standard methods in these languages may be inefficient for files of this size.

The database follows a structured versioning system aligned to changes the custom schema provided with this data release (NXSDB_schema_v1.2.0.json), which defines and validates the GeoPackage structure. This approved version of the database (v1.2.0) supersedes the previous version, which was provisionally published to incorporate improvements based on user feedback. A detailed record of changes is provided in the accompanying change_log.txt file. The previous version remains accessible as a tagged instance within a ZIP package so users can continue to access it if needed. The station master file (NXSDB_WY2023_CONUS_station_master.txt) lists all stations evaluated for inclusion. Stations that appear in this list but are absent from the GeoPackage had no cross-sections meeting the database’s inclusion criteria. Further processing details are available in the accompanying metadata XML file and README.