Leverage existing nutrient input/output data from the Chesapeake Bay Program's CAST database to develop nitrogen and phosphorus inventories. These inventories will highlight spatiotemporal variability in point and non-point source pollution throughout the watershed, and can be used to monitor progress in decreasing pollution sources as well as retrospective water quality analyses looking to explain past water quality trends. This dataset is associated with the following publication: Sabo, R., B. Sullivan, C. Wu, E. Trentacoste, Q. Zhang, G. Shenk, G. Bhatt, and L. Linker. Major point and nonpoint sources of nutrient pollution to surface water have declined throughout the Chesapeake Bay watershed. Environmental Research Communications. IOP Publishing, PHILADELPHIA, PA, USA, 4: 1-19, (2022).

Leverage existing nutrient input/output data from the Chesapeake Bay Program's CAST database to develop nitrogen and phosphorus inventories. These inventories will highlight spatiotemporal variability in point and non-point source pollution throughout the watershed, and can be used to monitor progress in decreasing pollution sources as well as retrospective water quality analyses looking to explain past water quality trends. This dataset is associated with the following publication: Sabo, R., B. Sullivan, C. Wu, E. Trentacoste, Q. Zhang, G. Shenk, G. Bhatt, and L. Linker. Major point and nonpoint sources of nutrient pollution to surface water have declined throughout the Chesapeake Bay watershed. Environmental Research Communications. IOP Publishing, PHILADELPHIA, PA, USA, 4: 1-19, (2022).

To estimate changes in nitrogen, phosphorus, and sediment loads from technologies and management practices (TMPs), the Chesapeake Bay Program Partnership's CAST model was used to run scenarios with and without TMPs for years between 1985 and 2020 for the Chesapeake Bay watershed. Scenarios were run using the native model segmentation of land-river segments and downscaled to the National Hydrography Dataset (NHD) plus version 2 catchments. The land-river segment loads were disaggregated to the National Hydrography Dataset Plus, Version 2.0 using methods described in "CAST Data Input Disaggregation from County and Land-River Segment Scale to National Hydrography Dataset Plus". The estimated total nitrogen (TN), total phosphorus (TP), and total suspended solids (TSS) for each scenario are in the data and are organized by the NHDPlus v2 catchments. There are 50,336,640 rows of data. The data include the amount of each contaminant that is delivered to the edge of a small stream. These data allow researchers to assess the overall impact of TMPs over time for various land uses. The data file is named ProgNA_RA_C1920220313. The file is uploaded as a zipped file and as a .txt file. The files are identical and the data user can choose the format that is best for them. The file name refers to the progress (prog) scenarios for each year with TMPs and the no action (NA) or no TMP scenarios with regulation air (RA) in CAST version 19 (C19) and the data were created on 3/13/2022.

Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in major rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay River Input Monitoring (RIM) Network stations for the period 1985 through 2020. Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). Yields (representing the mass of constituent transported from a unit area of a given watershed) are used to compare the export loads from one basin to another. Yield results are obtained by dividing the annual load (pounds) of a given constituent by the respective watershed area (acres) from which the constituent was transported. Yield results presented represent the average annual per-acre loads of nitrogen, phosphorus, and suspended sediment exported from each of the Chesapeake Bay River Input Monitoring stations for two possible time periods: 2011-2020 (10 year average yield) and 2016-2020 (5 year average yield).

Nitrogen pollution from contributing sources in Bay watershed, pounds per year. 1985, 2007, and 2009 - 2012 progress; 2017 and 2025 targets. Data source: EPA Phase 5.3.2 Watershed Model.

The dataset contains estimates for total nitrogen and total phosphorus loads from point sources, combined sewer overflows, wastewater treatment plants that discharge to surface water for selected Chesapeake Bay watersheds. For source information, please refer to the process steps in this metadata report.

Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in major rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay River Input Monitoring (RIM) Network stations for the period 1985 through 2022. Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). Yields (representing the mass of constituent transported from a unit area of a given watershed) are used to compare the export loads from one basin to another. Yield results are obtained by dividing the annual load (pounds) of a given constituent by the respective watershed area (acres) from which the constituent was transported. Yield results presented represent the average annual per-acre loads of nitrogen, phosphorus, and suspended sediment exported from each of the Chesapeake Bay River Input Monitoring stations for two possible time periods: 2013-2022 (10 year average yield) and 2018-2022 (5 year average yield).

This study uses the hierarchical CAFE (Cropping system, Animal-crop system, Food system, and Ecosystem) framework to evaluate nutrient management performances within the Chesapeake Bay watershed. This dataset contains a three-decade, county-level nutrient budget (1985–2019), which can be used to analyze the spatiotemporal patterns of N and P budgets, as well as N and P use efficiencies, within the four CAFE hierarchies. This dataset is associated with the following publication: Zou, T., E. Davidson, R. Sabo, G. MacDonald, and X. Zhang. Disparities in nitrogen and phosphorus management across time and space: a case study of the Chesapeake Bay using the CAFE framework. Environmental Research Letters. IOP Publishing LIMITED, Bristol, UK, Volume 19: 110016, (2024).

Nitrogen, phosphorus, and suspended-sediment loads, and changes in loads, in major rivers across the Chesapeake Bay watershed have been calculated using monitoring data from the Chesapeake Bay River Input Monitoring (RIM) Network stations for the period 1985 through 2020. Nutrient and suspended-sediment loads and changes in loads were determined by applying a weighted regression approach called WRTDS (Weighted Regression on Time, Discharge, and Season). The load results represent the total mass of nitrogen, phosphorus, and suspended sediment that was exported from each of the RIM watersheds.

Chesapeake Bay restoration solutions, Best Management Practices (BMPs), progress reporting by tributary basin.