Estimated Nitrogen, Phosphorus, and Sediment Load Reductions from Best Management Practices in the Chesapeake Bay Watershed between 1985 and 2020

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.