Real-time USGS nitrate data are collected to map short-term changes in nitrate concentrations across locations in the US: https://waterwatch.usgs.gov/wqwatch/?pcode=00630 CAMELS data are “a large-sample watershed-scale hydrometeorological dataset for the contiguous USA” (see https://gdex.ucar.edu/dataset/camels.html) BasinATLAS for catchment attributes related to land cover, soils, and geology: https://developers.google.com/earth-engine/datasets/tags/hydroatlas DAYMET meteorological data for temperature and precipitation: https://daymet.ornl.gov/. This dataset is not publicly accessible because: Publicly available data. It can be accessed through the following means: https://waterwatch.usgs.gov/wqwatch/?pcode=00630 https://gdex.ucar.edu/dataset/camels.html https://developers.google.com/earth-engine/datasets/tags/hydroatlas https://daymet.ornl.gov/. Format: Real-time USGS nitrate data, CAMELS streamflow data, BasinATLAS catchment attribute data, and DAYMET meteorological data. This dataset is associated with the following publication: Pandit, A., H. Golden, J. Christensen, C. Lane, and A. Husic. Deep Learning Prediction and Interpretation of Riverine Nitrate Export Across the Mississippi River Basin. WATER RESOURCES RESEARCH. American Geophysical Union, Washington, DC, USA, 61(8): e2024WR039207, (2025).