This dataset summarizes impairment status for HUC12 watersheds at the CONUS scale using the EPA publicly available Assessment, Total Maximum Daily Load (TMDL) Tracking and Implementation System (ATTAINS) geospatial package and the USGS Watershed Boundary Dataset (WBD). ATTAINS is an online system maintained by the EPA containing information about the condition of the Nation’s surface waters, as reported by individual states. These data were downloaded in October 2023 and primarily reflect 2022 stream conditions. Because of the varying data types that exist in the database, an independent methodology was developed for summarizing impairment status for HUC12 watersheds using the USGS WBD as detailed in this metadata record. These process steps ensured consistency, standardization, and transparency of various spatial attributes. HUC12 watersheds flagged as “Impaired” indicate there are impaired waters within the HUC12 watershed, but does not imply all waters within the HUC12 are listed as impaired. A supplemental table indicating the cause of impairment at the HUC12 scale, where known, is also provided.

This data release contains a crosswalk between subwatersheds (12-digit hydrologic unit codes; hereafter, HUC12s) and hydrologic regions (sometimes called "Van Metre regions"). This crosswalk allows for data at the HUC12 scale to be summarized regionally. Hydrologic regions are boundaries of hydrologically distinct areas modified from hydrologic subregions (4-digit Hydrologic units; HUC4s) defined by Qi and Mason (2023; https://doi.org/10.5066/P98194QR) for use in Van Meter et al. (2020; https://doi.org/10.1007/s10661-020-08403-1). These hydrologic regions should not be confused with 2-digit hydrologic unit codes (HUC2 or HU2), also referred to as "hydroregions" or "HydroRegions." Although they are similar in number and size, they represent different concepts: HUC2s denote drainage basins of major rivers, while the hydrologic regions defined by Van Metre et al. (2020) are areas with similar hydrology and water availability concerns that were originally developed to help inform selection of basins for more in-depth sampling, analysis, and modeling. For comparative purposes, we further grouped the hydrologic regions into four CONUS aggregated hydrologic regions based on location and shared water-availability characteristics and challenges (Northeast through Midwest, Southeast, High Plains, and Western). The HUC12 boundaries used are those made available in the Mainstems data release (https://doi.org/10.5066/P92U7ZUT), which are modified from the stable NHDPlusV2 snapshot of the Watershed Boundary Dataset.

This child item provides a snapshot of the watershed boundary dataset which consists of a shapefile with 87,020 12-digit hydrologic unit codes (HUC12) for the conterminous United States retrieved 10/26/2020. The National Watershed Boundary Dataset (WBD) is a comprehensive set of digital spatial data that represents the surface drainages areas of the United States. Although versions of the WBD are published as part of U.S. Geological Survey National Hydrography Products, the version used to produce the water-use reanalysis was not archived and is provided here. This dataset is part of a larger data release using machine learning to predict public supply water use for 12-digit hydrologic units from 2000-2020. Public-supply water use estimates for the HUC12s included in this shapefile are provided on the data release main landing page and on the public supply water use machine learning model child item. This page includes the following file: WBD_HUC12_CONUS_pulled10262020.zip - a zi ...

This is a shapefile of watershed boundaries for CONUS using 12-digit Hydrologic Unit Codes. Data are projected into the WRF-Hydro Lambert Conformal Conic (variant) spatial reference system. This is defined as "+proj=lcc +lat_1=30 +lat_2=60 +lat_0=40.0000076293945 +lon_0=-97 +x_0=0 +y_0=0 +a=6370000 +b=6370000 +units=m +no_defs"

The USGS has published United States water-use data every five years since 1950. To increase the temporal and spatial availability of water use estimates using nationally consistent methods, the USGS is developing national water-use models for each major water-use category. This data release publishes crop irrigation withdrawals for the conterminous United States (CONUS) that are calculated using modeled irrigation consumptive use (Martin and others, 2023), irrigation efficiencies, and source-water proportions (Dieter and others, 2018). Crop irrigation withdrawals and irrigation consumptive use refer to water removed and consumed, respectively, from a groundwater or surface-water source to produce agricultural crops. Monthly withdrawals provided include groundwater, surface water, and the combined total withdrawal for areas contained in the twelve-digit watershed boundary (HUC12) dataset during the reanalysis period, 2000-2020. HUC12 annual 2000-2020 irrigation efficiencies included in this data release combine efficiencies from irrigation system types (accounting for water lost during application to crops) and conveyances (accounting for water lost during transmission through canals and pipes). Irrigated crops were mapped using the Landsat-based Irrigation Dataset (LANID; Xie and Lark, 2021; Martin and others, 2023) and the Cropland Data Layer (USDA NASS, 2022) that were linked to irrigation system types (USDA NASS, 2014) to estimate irrigation system efficiencies for each HUC12 in the CONUS (Howell, 2003 and FAO, 1989). Conveyance loss volumes (USDA NASS, 2020) were used to estimate and map surface-water conveyance efficiencies. Total efficiencies were calculated for HUC12 units by combining irrigation system and conveyance efficiencies. Irrigation withdrawals and efficiencies were produced using published data sources to provide these estimates in a timely manner. On-going work to develop dynamic maps of irrigation system type and other datasets for the CONUS will be used in the future to refine the estimates provided here. Estimation of irrigation withdrawals using irrigation consumptive use and efficiencies neglects some components of water use for crops, including water used for frost protection, salt leaching, harvesting, and other non-consumptive-use based treatments. For this reason, irrigation withdrawals provided here may under-estimate total withdrawals where non-consumptive treatments are significant.

This dataset contains topographic, climatic and land cover attributes for headwaters (stream orders 1 and 2 ) as defined by the National Hydrography Dataset High Resolution (NHDHR) and downstream areas (stream orders 3 and up) for a subset of Conterminous United States (CONUS) HUC12s. Specifically, this dataset contains 2021 National Land Cover Database (NLCD) land cover for the following categories: water, developed, forest, shrubland/grassland, crops/hay; topographic metrics including: area, slope, elevation, stream density, stream length, stream slope and depth to bedrock; climatic metrics including aridity and snow persistence; and soil metrics including clay, silt and sand.

This data release provides a monthly irrigation water use reanalysis for the period 2000-20 for all USGS Watershed Boundary Dataset of Subwatersheds (Hydrologic Unit Code 12 [HUC12]) in the conterminous United States (CONUS). Results include reference evapotranspiration (ETo), actual evapotranspiration (ETa), irrigated areas, consumptive use, and effective precipitation for each HUC12. ETo and ETa were estimated using the operational Simplified Surface Energy Balance (SSEBop, Senay and others, 2013; Senay and others, 2020) model executed in the OpenET (Melton and others, 2021) web-based application implemented in Google Earth Engine. Results provided by OpenET/SSEBop were summarized to hydrologic response units (HRUs) in the National Hydrologic Model (NHM; Regan and others, 2019) to estimate consumptive use and effective precipitation on irrigated lands. Irrigated lands for the CONUS were provided by the Landsat-based Irrigation Dataset (LANID; Xie and others, 2019) for each year of the reanalysis period. Consumptive use estimates provided by the NHM were disaggregated to HUC12s using area weighted intersections with HRUs and the relative proportion of irrigated lands in each intersected area. This data release includes data and source code required to develop the irrigation reanalysis workflow along with the scripts and data required to replicate the output results. The workflow has three main steps that were automated using python scripts: 1) convert daily OpenET/SSEBop results into input for the NHM, 2) run a modified version of the NHM that is an application of the GSFLOW software package (GSFLOW version 2.3) to estimate daily results, and 3) post-process NHM results to monthly, then summarize and disaggregate ETo, ETa, irrigated areas, consumptive use, and effective precipitation to all HUC12s in the CONUS for the period 2000-20.

These data are a summary of Public Water Systems (PWS) and populations receiving surface drinking water supply from National Forest System (NFS) lands managed by the USDA Forest Service in the conterminous United States (CONUS). The PWS in these data include only those receiving some portion of their surface water supply from NFS lands, either through the intakes they manage or through water purchases from other PWS that receive some portion of their surface water supply from NFS lands. To generate these data, unique model input databases were created for each of the 172 NFS units in the CONUS and water supply from each NFS unit and other non-NFS lands were simulated and tracked through the river network using the Water Supply and Stress Index (WaSSI) model while including inter-basin transfers (IBTs). Water supply outputs were then linked to the Environmental Protection Agency’s Safe Drinking Water Information System (SDWIS) database of public surface drinking water intakes. When a PWS had more than one intake, the percentage of the total surface drinking water originating on the individual NFS unit for the public water system was calculated from the total available water and the total water from the individual NFS unit across all intakes for the public water system. In addition to results at the NFS unit level, Watershed Boundary Dataset (WBD) Watershed 12-digit Hydrologic Unit Code (HUC12) subwatersheds that contain NFS units and provide surface drinking water supply to PWSs are identified and summarized. Purchasing PWS in the SDWIS were included for those PWS that had an associated selling PWS with surface water intakes that received some portion of their water from NFS lands, and the purchasing PWSs did not have their own surface water intakes and therefore would already be in the database. Also included are results aggregated across all NFS units in each Forest Service Region.The objectives of this analysis were to (1) estimate how much fresh surface water supply originates from NFS lands, and (2) estimate how many people and which communities receive this fresh surface water supply.This data publication (second edition) was published on 03/31/2022 and supersedes that of https://doi.org/10.2737/RDS-2021-0098 (first edition). Changes to the original version include the following. The first edition included information on PWS intake facilities whose PWS-level primary water source was surface water or groundwater under the influence of surface water but whose facility-level water type was groundwater or groundwater purchased. Those facilities whose facility-level water type was groundwater or groundwater purchased were removed from this second edition. Secondly, this new edition includes three additional tables: All_NFS_Purchased.csv, FS_Region_Purchased.csv, and NFS_Unit_Purchased.csv. These tables provide additional information for those PWSs in the SDWIS that had an associated selling PWS with surface water intakes that received some portion of their water from NFS lands, and the purchasing PWSs did not have their own surface water intakes and therefore would already be in the database.

On 07/22/2022 this second edition was updated to include two additional tables (NFS_Unit_HUC12.csv and NFS_Unit_HUC12_PWS.csv) that provide additional information about PWSs that receive surface drinking water supply from particular HUC12 subwatersheds containing NFS units. Also added were geospatial files containing the HUC12 subwatershed boundaries corresponding to those referenced in the new tables. On 09/20/2022 the metadata for this second edition was updated to include reference to the newly published General Technical Report by Liu et al. (2022).

For more information about these data see Liu et al. (2022).

Full FGDC Metadata This map displays predicted probability of a 12-digit Hydrologic Unit (HUC12) being at risk of violating the drinking water nitrate standard. Risk is defined as there being greater than a 50% chance of having a drinking water violation. Observed violations of the nitrate standard in public drinking water was used to make predictions across the conterminous United States. The data on nitrate violations comes from the EPA's Safe Drinking Water Information System (SDWIS) and the data used as predictor variables in the prediction models comes from EPA's StreamCat database. The original predictions were made at the National Hydrography Dataset (NHD) Catchment scale and summarized at the HUC12 scale and/or 300 m pixel scale. The maps show that 19% of the conterminous United States is at risk of groundwater sourced drinking violations, while 16% of the U.S. is at risk of nitrate violations from surface water sources. Regions with the highest risk of nitrate drinking violations from groundwater sources are found in the southwest, south central plains, parts of north west, mid-Atlantic. Surface water sourced nitrate violations have the greatest risk primarily in the southwest and south-central areas of the U.S. Table Download This is only the data table. To associate with 12-digit HUC polygons - download https://enviroatlas.epa.gov/download/NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS.gdb.zipThis dataset was produced by the USDA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

This data release provides a monthly irrigation water use reanalysis for the period 2000-20 for all U.S. Geological Survey (USGS) Watershed Boundary Dataset of Subwatersheds (Hydrologic Unit Code 12 [HUC12]) in the conterminous United States (CONUS). Results include reference evapotranspiration (ETo), actual evapotranspiration (ETa), irrigated areas, consumptive use, and effective precipitation for each HUC12. ETo and ETa were estimated using the operational Simplified Surface Energy Balance (SSEBop, Senay and others, 2013; Senay and others, 2020) model executed in the OpenET (Melton and others, 2021) web-based application implemented in Google Earth Engine. Results provided by OpenET/SSEBop were summarized to hydrologic response units (HRUs) in the National Hydrologic Model (NHM; Regan and others, 2019) to estimate consumptive use and effective precipitation on irrigated lands. Irrigated lands for the CONUS were provided by the Landsat-based Irrigation Dataset (LANID; Xie and others, 2019) for each year of the reanalysis period. Consumptive use estimates provided by the NHM were disaggregated to HUC12s using area weighted intersections with HRUs and the relative proportion of irrigated lands in each intersected area. The Landsat-based Irrigation Dataset (LANID) uses a random-forest machine-learning model with greenness and vegetative indices, climate data, and crop masks to identify irrigated crops (Xie and others, 2021, Xie and Lark, 2021). Separate western US and eastern US methods are used to train and validate the model. Annual LANID maps for 2018 -20 were created using the same techniques in Xie and others, 2021, and Xie and Lark, 2021.

Full FGDC Metadata This EnviroAtlas dataset represents the percentage land area that is classified as agricultural land cover that occurs on slopes above a given threshold for each 12-digit hydrologic unit code (HUC) in the conterminous United States. Agricultural land cover is defined using the EnviroAtlas hybrid Cropland Data Layer (CDL) - 2011 National Land Cover Dataset (NLCD). Percentage slope values were derived from the 1 arc-second National Elevation Dataset (NED).Table download This is only the data table. To associate with 12-digit HUC polygons - download https://enviroatlas.epa.gov/download/NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS.gdb.zip This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

Full FGDC Metadata This EnviroAtlas dataset is a summary of the National Dams Inventory data from 2009 survey. The file contains counts of inventoried dams by 12-digit hydrologic units codes (March 2011) and total maximum storage capacity in millions of gallons.Table download This is only the data table. To associate with 12-digit HUC polygons - download https://enviroatlas.epa.gov/download/NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS.gdb.zipThis dataset was produced the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

Full FGDC Metadata This dataset shows the percentage of each National Hydrography Dataset Plus (NHDPlus) V2 12-digit Hydrologic Unit (HUC) that is included in the USGS National Gap Analysis Program (GAP) or International Union for the Conservation of Nature (IUCN) protection categories in the Protected Areas Database of the United States (PADUS). Percentages for GAP status 1 and 2 combined, GAP status 3, and GAP status 1, 2, and 3 combined are provided. The percentages for IUCN categories Ia, Ib, II, III, IV, V, and VI are provided, as well as for all the categories combined.Table download This is only the data table. To associate with 12-digit HUC polygons - download https://enviroatlas.epa.gov/download/NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS.gdb.zipThis dataset was produced the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

Full FGDC Metadata This EnviroAtlas dataset contains the percentage of small, medium, and large natural areas for each Watershed Boundary Dataset (WBD) 12-Digit Hydrologic Unit Code (HUC-12) of the conterminous United States that is considered Natural based on the National Land Cover Database (NLCD). The percentage of natural area is by size class: Small is <500 acres, Medium is 500-25,000 acres, and Large is > 25,000 acres. Natural land cover combines NLCD-CDL 63, 83, 87, 111, 112, 131, 141, 142, 143, 151, 152, 171, 190, 195. This dataset was produced by the Tetra Tech, Inc.Table download This is only the data table. To associate with 12-digit HUC polygons - download https://enviroatlas.epa.gov/download/NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS.gdb.zipThis dataset was produced the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

Full FGDC Metadata This EnviroAtlas dataset is a summary of the thermoelectric water consumption based on the December 2016 US Energy Information Administration (EIA) monthly electric generator inventory, a 2014 review of water consumption for electricity generation (Macknick et al.), and reported water consumption estimates from a 2009 Department of Energy (DOE) report. The file contains total water withdrawal and consumption in gallons per year by 12-digit hydrologic unit codes (HUC_12s) from the boundary file named NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS.Table download This is only the data table. To associate with 12-digit HUC polygons - download https://enviroatlas.epa.gov/download/NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS.gdb.zipThis dataset was produced the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

Public Water System location points, based on information from the Safe Drinking Water Act Information System (SDWIS/Federal) for a 2010 third quarter (SDWIS_2010Q3) baseline period, were applied to relate system latitude and longitude coordinates (LatLongs) to Watershed Boundary Dataset subwatershed polygons (HUC12s). This HUC12 table can be mapped through setting up appropriate table relationships on the attribute "HUC_12" with the HUC12 GIS layer that is part of EPA's Reach Address Database (RAD) Version 3. At the present time, the RAD Version 3 contains HUC12 polygons for the conterminous United States (CONUS), Hawaii, Puerto Rico, and the U.S. Virgin Islands (materials for Alaska or for other territories and dependencies are not available as of February, 2010). The records in this table are based on a special QUERY created by the EPA Office of Ground Water and Drinking Water (OGWDW) from the primary SDWIS/FED information to provide a robust point representation for a PWS system. PWS points are selected based on the following prioritization: 1. If the system has a treatment plant with LatLongs and MAD codes; 2. If the system has a treatment plant with LatLongs but without MAD codes; 3. If the system has a well with LatLongs and MAD codes; 4. If the system has a well with LatLongs but without MAD codes; 5. If the system has an intake with LatLongs and MAD codes; 6. If the system has an intake with LatLongs but without MAD codes; 7. If the system has any source with LatLongs and MAD codes; 8. If the system has any source with LatLongs but without MAD codes. Note: Public water systems and the populations served by the systems may not be located within the same HUC12 as the sources of drinking water.

Full FGDC Metadata The national agricultural water demand metric provides insight into the amount of water used for agricultural irrigation in the contiguous United States. The estimates are derived from a water usage rate per 30m cell based on 2010 irrigation water use; an indication of agricultural irrigation based on 2011 crop, 2011 land use, and 2007/2012 remotely sensed irrigation; and summarized by watershed or 12-digit hydrologic unit code (HUC). Agricultural irrigation water use, as defined in this case, meets a variety of needs before, during, and after growing seasons (e.g., dust suppression, field preparation, chemical application, weed control, salt removal from root zones, frost protection, crop cooling, and harvesting). Estimates include self-supplied surface and groundwater, as well as supplies from irrigation-specific organizations (e.g., companies, districts, cooperatives, government).Table download This is only the data table. To associate with 12-digit HUC polygons - download https://enviroatlas.epa.gov/download/NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS.gdb.zipThis dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

This data release contains the output from an ecological analysis modeling the exposure of 214 fish taxa across the conterminous US (CONUS) to an index of surface water supply and use imbalances (SUI), the proportion of monthly gross average water supply available after accounting for climate variation and consumptive use, during their spawning months, hereafter referred to as spawning exposure. SUI were calculated in Miller and others (2024) by combining the monthly water balance from water supply and human consumptive uses for CONUS from water years 2010-2020 at the HUC12 scale. Water supply inputs were generated from two physically-based hydrologic models, and consumptive water use was calculated from three separate national models for agricultural irrigation, thermoelectric power generation, and public supply. Water budgets were routed through the surface water flow network (to allow for upstream consumptive uses to affect downstream water availability) and used to determine potential water limitations for human populations and fish taxa. We overlaid water supply imbalances with the modeled ranges of 241 fish taxa, including Species of Greatest Conservation Need, recreationally important, and common native taxa. SUI were evaluated within each HUC12 and specifically mean weighted based on the probability of spawning in each month for each taxa. Our analyses indicated multiple taxa having notable proportions of their habitats exposed to high or severe water imbalances during spawning, especially the federally-listed Arkansas River shiner. This analysis can be used to identify fish taxa particularly exposed to water availability issues, specifically from surface water supply and use imbalances, during the physiologically important spawning period. However, this analysis did not consider specific taxa-level differences as to the sensitivity of different taxa to limited water supply. This data release contains five tabular datasets in comma-separated values (.csv), covering a tabular data dictionary, input data supporting analysis, raw analysis output, and summarized versions at two spatial scales for convenience. They are: 1) data_dictionary.csv - A data dictionary containing entity and attribute information about variable names, descriptions, types, ranges, and unique values for easy access. 2) SpawningExposure_TaxaSpawningWeights.csv - Dataset used to weigh spawning months for each taxon in calculation of the spawning exposure. Derived from Frimpong and Angermeier, 2011. 3) SpawningExposure_SUI_HUC12.csv - CONUS level dataset of spawning exposure to SUI from 2010-2020 for each fish taxa reported for each HUC12 where they are present. 4) SpawningExposure_SUI_CONUS_Summary.csv - A summary of spawning exposure to SUI by fish taxa, for the entire habitat range in CONUS, the range-averaged SUI exposure and percentage of habitat in each SUI category class. 5) SpawningExposure_SUI_Regional_Summary.csv - Summaries of spawning exposure to SUI by fish taxa, for each Van Metre (2020) hydrologic region, the region range-average exposure and percentage of the region's habitat range in each SUI category class.

Full FGDC Metadata This EnviroAtlas dataset contains data on the mean synthetic nitrogen (N) fertilizer application to cultivated crop and hay/pasture lands per 12-digit Hydrologic Unit (HUC) in 2006. Synthetic N fertilizer inputs in 2006 were estimated using county-level estimates of farm N fertilizer inputs. We acquired county-level data describing total farm-level inputs (kg N/yr) of synthetic N fertilizer to individual counties in 2006 from the United States Geological Survey (USGS) (https://pubs.usgs.gov/sir/2012/5207/). These data were converted to per area rates (kg N/ha/yr) of synthetic N fertilizer application by dividing the total N input by the land area (ha) of combined cultivated crop and hay/pasture lands within a county as determined from county-level (https://cta.ornl.gov/transnet/Boundaries.html) summarization of the 2006 National Land Cover Database (NLCD; https://www.mrlc.gov/nlcd06_data.php). We distributed county-specific, annual per area N inputs rates (kg N/ha/yr) to cultivated crop and hay/pasture lands (30 x 30 m pixels) within the corresponding county using the raster calculator tool in ArcMap 10.0 (ESRI, Inc., Redlands, CA). Fertilizer data described here represent an average input to a typical agricultural land type within a county, i.e., they are not specific to individual crop types.Table Download This is only the data table. To associate with 12-digit HUC polygons - download https://enviroatlas.epa.gov/download/NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS.gdb.zipThis dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

Full FGDC Metadata This EnviroAtlas dataset contains a count of the number of local farmers markets within each subwatershed (12-digit HUC) based on their location given within the USDA National Farmers Market Directory (https://www.ams.usda.gov/local-food-directories/farmersmarkets). This data has been processed from the original directory to remove duplicate locations, as well as a small subsample (25 markets) were corrected by hand in order avoid duplication across block group boundaries. This dataset is contemporary as of 5/20/2016, and downloaded from the USDA Agricultural Marketing Service (AMS) website.Table Download This is only the data table. To associate with 12-digit HUC polygons - download https://enviroatlas.epa.gov/download/NHDPlusV2_WBDSnapshot_EnviroAtlas_CONUS.gdb.zipThis dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).