The LakeCat Dataset: Accumulated Attributes for NHDPlusV2 (Version 2.1) lake catchments and watersheds for the Conterminous United States: Facility Registry Services (FRS) : Toxic Release Inventory (TRI) , National Pollutant Discharge Elimination System (NPDES) , and Superfund Sites

This dataset represents the estimated density of georeferenced sites within individual local and accumulated upstream catchments for NHDPlusV2 Waterbodies based on the EPA's Facility Registry Services (FRS) geodatabase (See Supplementary Info for Glossary of Terms). Catchment boundaries in LakeCat are defined in one of two ways, on-network or off-network. The on-network catchment boundaries follow the catchments provided in the NHDPlusV2 and the metrics for these lakes mirror metrics from StreamCat, but will substitute the COMID of the NHDWaterbody for that of the NHDFlowline. The off-network catchment framework uses the NHDPlusV2 flow direction rasters to define non-overlapping lake-catchment boundaries and then links them through an off-network flow table (See LakeCat Documentation for this processing framework). The FRS geodatabase is a collection of point locations of facilities or sites subject to environmental regulation. TRI, NPDES, and Superfund sites were extracted individually to summarize for each in the resulting .csv. (see Data Sources for links to NHDPlusV2 data and FRS data) The (site locations / catchment) were summarized and accumulated into watersheds to produce local catchment-level and watershed-level metrics as a points data type (see Data Structure and Attribute Information for a description of each metric).