Hydrologic landscape regions (HLRs) in the United States were delineated by using geographic information system (GIS) tools and statistical methods including principal components and cluster analyses. The GIS and statistical analyses were applied to land-surface form, geologic texture (permeability of the soil and bedrock), and climate variables that describe the physical and climatic setting of 43,931 small (roughly 200 square kilometers) watersheds in the United States. The analyses then grouped the watersheds into 20 noncontiguous regions (the HLRs) on the basis of similarities in land-surface form, geologic texture, and climate characteristics. This hydrologic landscape regions dataset contains for each of the 43,931 watersheds the (1) watershed identification number, (2) land-surface form, geologic texture, and climate characteristics for each watershed, and (3) hydrologic landscape region number for each watershed.

This U.S. Geological Survey (USGS) data release consists of two hydrographic datasets with spatial modeling units, two sets of spatial data consistent with the National Hydrologic Model (NHM) Geospatial Fabric for National Hydrologic Modeling (abbreviated within this document as GFv1, Viger and Bock, 2014), and a database of 118 parameters used to run the NHM . These datasets are found as subpages to this landing page as 1) the GIS (geographic information system) features of the United States-Canada Transboundary Geospatial Fabric (TGF, added 08/04/2020), 2) the GIS features of the Geospatial Fabric v1.1 (GFv1.1 or v1_1, added 08/04/2020) which is an update to the GF and includes the TGF, 3) Topographic derivative datasets for the United States-Canada transboundary Geospatial Fabric (added 10/28/2020), 4) Data Layers for the National Hydrologic Model, version 1.1, and 5) National Hydrologic Model's United States-Canada Transboundary Geospatial Fabric Parameter Database (added 11/10/2021). See subpages for more details.

This workbook summarizes nutrient geochemical data for each lithology contained within the USGS Preliminary Integrated Geologic Map Databases for the United States (Open File Reports 2004-1355, 2005-1305, 2005-1323, 2005-1324, 2005-1325, 2005-1351, and 2006-1272). The geochemical attributes in the “Lith Summary” spreadsheet (tab) are measures of central tendency for all whole rock analyses publically available at the time of creation for 284 lithologies, reported as percent sulfur and nitrogen. Further details on how data were summarized and sources for geochemical data are contained in the “ReadMe” spreadsheet (tab).

This workbook summarizes geochemical data for each lithology contained within the USGS Preliminary Integrated Geologic Map Databases for the United States (Open File Reports 2004-1355, 2005-1305, 2005-1323, 2005-1324, 2005-1325, 2005-1351, and 2006-1272). The geochemical attributes in the “Lith Summary” spreadsheet (tab) are measures of central tendency for all whole rock analyses publically available at the time of creation for 279 lithologies, reported as percent oxide. Further details on how data were summarized and sources for geochemical data are contained in the “ReadMe” spreadsheet (tab).

This U.S. Geological Survey (USGS) data release record consists of topographic data themes that cover the United States-Canada Transboundary Geospatial Fabric (TGF) domain. The 30-meter (m) raster data sets included under Topographic Derivatives are: 1) digital elevation (dem.tif) , 2) topographic wetness index (TWI, twi100X.tif) ,3) slope (rise over run, slope100X.tif), 4) aspect (asp100X.tif), and flow direction (fdr.tif). In some instances, values were multiplied by 100 and converted from double precision to integer format to reduce file sizes. All file formats are in GeoTIFF (Geographic Tagged Imaged Format).

The Geospatial Fabric version 1.1 (GFv1.1 or v1_1) is a dataset of spatial modeling units covering the conterminous United States (CONUS) and most major river basins that flow in from Canada. The GFv1.1 is an update to the original Geospatial Fabric (GFv1, Viger and Bock, 2014) for the National Hydrologic Modeling (NHM). Analogous to the GFv1, the GFv1.1 described here includes the following vector feature classes: points of interest (POIs_v1_1), a stream network (nsegment_v1_1), and hydrologic response units (nhru_v1_1), with several additional ancillary tables. These data are contained within the Environmental Systems Research Institute (ESRI) geodatabase format (GFv1.1.gdb).

The Geospatial Fabric version 1.1 (GFv1.1 or v1_1) is a dataset of spatial modeling units covering the conterminous United States (CONUS) and most major river basins that flow in from Canada. The GFv1.1 is an update to the original Geospatial Fabric (GFv1, Viger and Bock, 2014) for the National Hydrologic Modeling (NHM). Analogous to the GFv1, the GFv1.1 described here includes the following vector feature classes: points of interest (POIs_v1_1), a stream network (nsegment_v1_1), and hydrologic response units (nhru_v1_1), with several additional ancillary tables. These data are contained within the Environmental Systems Research Institute (ESRI) geodatabase format (GFv1.1.gdb).

The U.S. Geological Survey (USGS) previously identified 62 Principal Aquifers (PAs) in the U.S., with 57 located in the conterminous states. The USGS characterized areas outside of PAs as “other rocks;” other rocks account for about 40% of the area of the conterminous states. This paper subdivides the large area identified as other rocks into Secondary Hydrogeologic Regions (SHRs). SHRs are defined as areas of other rock within which the rocks are of comparable geologic age, lithology, and relationship to the presence or absence of underling PAs or overlying glacial deposits. A total of 69 SHRs were identified. SHRs were identified in two phases. In the first phase, Other Rock Regions (ORRs) were defined as regions underlain by geologic units of comparable age, lithology, and geologic or physiographic setting. ORRs were an intermediate product. In the second phase, ORRs were evaluated relative to the presence of PAs that may underlie the ORRs and (or) glacial deposits that may overly the ORRs. The presence or absence of stream-valley aquifers overlying an SHR was not considered, which is consistent with the identification of PAs. Identification and mapping of ORRs and SHRs was facilitated using digital databases and geographic information system tools. The SHRs were classified using three criteria: (1) presence or absence of underlying PAs or overlying glacial deposits, (2) primary lithology, and (3) geologic province and subprovince. The number and size of SHRs identified in this paper are comparable to the number and size of PAs previously identified by the USGS. With the identification of SHRs, all areas of the conterminous U.S. belong to an internally consistent mapped feature, thus providing a comprehensive framework for assessing groundwater at regional and national scales. Figures 1-3 are included for reference. Files are provided in Portable Network Graphic (PNG) format: Figure 1. Map showing the 69 Secondary Hydrogeologic Regions of the conterminous United States. Figure 2. Maps showing Secondary Hydrogeologic Regions (SHRs) classified by (A) Type; (B) Lithologic class, and (C) Geologic province and subprovince. Figure 3. Map showing Community Supply Wells (Price and Maupin, 2014) classified by the type of Secondary Hydrogeologic Region (SHR) that the well plots within. Type refers to the presence of a Principal Aquifer beneath (first letter) or glacial deposits above a SHR (second letter); Y= yes, present, and N = no, not present. There are about 143,000 wells shown: 9% are in SHRs classified as Type NN, 13% in Type NY, 3% in type YN, and 4% in Type YY; 71% are in Principal Aquifers.

This U.S. Geological Survey (USGS) metadata release consists of 17 different spatial layers in GeoTIFF format. They are: 1) average water capacity (AWC.zip), 2) percent sand (Sand.zip), 3) percent silt (Silt.zip), 4) percent clay (Clay.zip), 5) soil texture (TEXT_PRMS.zip), 6) land use/land cover (LULC.zip), 7) snow values (Snow.zip), 8) summer rain values (SRain.zip), 9) winter rain values (WRain.zip), 10) leaf presence values (keep.zip), 11) leaf loss values (loss.zip), 12) percent tree canopy (CNPY.zip), 13) percent impervious surface (Imperv.zip), 14) snow depletion curve numbers (Snow.zip), 15) rooting depth (RootDepth.zip), 16) permeability values (Lithology_exp_Konly_Project.zip), and 17) water bodies. All data cover the National Hydrologic Model's (NHM) version 1.1 domain. The NHM is a modeling infrastructure consisting of three main parts: 1) an underlying geospatial fabric of modeling units (hydrologic response units and stream segments) with an associated parameter database, 2) a model input data archive, and 3) a repository of the physical model simulation code bases (Regan and others, 2014). The NHM has been used for a variety of applications since its initial development.The 250-meter (m) raster data sets for soils are derived from the OpenGeoHub's LandGIS data (Hengl, 2018). The 30-meter raster of land use and land cover data are a simplified re-classification version of the North American Land-Change Monitoring System (NALCMS, Latifovic and others, 2012) data following the guidance in Viger and Leavesley (2007). This layer was used to derive rasters representing dominant vegetative cover type, snow, summer and winter rain interception values, leaf cover and loss, and rooting depth. The impervious data was compiled from the Global Man-made Impervious Surface (GMIS) Dataset from Landsat, v1 (NASA, 2010). The tree canopy data was compiled from MOD44B MODIS/Terra Vegetation Continuous Fields Yearly L3 Global 250m SIN Grid V006, (Carroll and others, 2017). The snow depletion data was compiled from data by Liston and others (2009) and further processed using methods by Sexstone and others (2020). All file formats are in GeoTIFF (Geograhpic Tagged Imaged Format).

The Geopspatial Fabric provides a consistent, documented, and topologically connected set of spatial features that create an abstracted stream/basin network of features useful for hydrologic modeling.The GIS vector features contained in this Geospatial Fabric (GF) data set cover the lower 48 U.S. states, Hawaii, and Puerto Rico. Four GIS feature classes are provided for each Region: 1) the Region outline ("one"), 2) Points of Interest ("POIs"), 3) a routing network ("nsegment"), and 4) Hydrologic Response Units ("nhru"). A graphic showing the boundaries for all Regions is provided at http://dx.doi.org/doi:10.5066/F7542KMD. These Regions are identical to those used to organize the NHDPlus v.1 dataset (US EPA and US Geological Survey, 2005). Although the GF Feature data set has been derived from NHDPlus v.1, it is an entirely new data set that has been designed to generically support regional and national scale applications of hydrologic models. Definition of each type of feature class and its derivation is provided within the section of this metadata document. The first entry in that section provides an overview of the delineation process, with each subsequent corresponding to one of the four types of feature. These entries describe the derivation of feature types in the order in which they are created. Minimal attribution (feature size, location, and routing connectivity) is provided for the feature classes within the GF Feature data set. More extensive feature attribution is published separately as individual tables of attributes(for example, http://dx.doi.org/doi:10.5066/F7RX9937) or via entire configurations of tables engineered to satisfy particular watershed models (for example, http://dx.doi.org/doi:10.5066/F7WM1BF7).