Accurate and efficient cross-section surveys are essential for maintaining high-quality stage-discharge ratings and index velocity gage operations. This presentation demonstrates a streamlined workflow for conducting differential level surveys of river cross-sections using the SVMobileAQ mobile application and importing the data into AreaComp3 software for visualization and analysis. The session will cover the fundamentals of setting up a conventional differential level instrument (level gun) and collecting cross-section data in the field with SVMobileAQ. Attendees will then learn how to seamlessly import the survey data into AreaComp3 to generate plotted cross-sections referenced to gage datum. Although commonly applied to index velocity gages, this approach provides broader benefits for streamgaging programs, including evaluation of control features at stage-discharge stations, detection of changes in channel geometry through overlay of historical surveys, and investigation of discrepancies by comparing survey results with ADCP bathymetry. This practical, field-to-office workflow offers an accessible and efficient method for improving the quality and utility of cross-section data in water resources monitoring.
In 2026 the National Geodetic Survey is releasing the North American-Pacific Geopotential Datum of 2022. This will have a wide range of implications on how we collect and disseminate spatial data. This session is an introduction to the new datum and its parts as well as discussion of how it will impact USGS Water systems and interpretive data.
This session will focus on a new tech memo from the NGS (NOS NGS 92). I will present the changes in field survey methods the NGS has outlined in the document and discuss potential changes to USGS GNSS data collection methods to bring us into compliance.
