Each drainage area is considered a Hydrologic Unit (HU) and is given a Hydrologic Unit Code (HUC) which serves as the unique identifier for the area. HUC 2s, 6s, 8s, 10s, & 12s, define the drainage Regions, Subregions, Basins, Subbasins, Watersheds and Subwatersheds, respectively, across the United States. Their boundaries are defined by hydrologic and topographic criteria that delineate an area of land upstream from a specific point on a river and are determined solely upon science based hydrologic principles, not favoring any administrative boundaries, special projects, or a particular program or agency. The Watershed Boundary Dataset is delineated and georeferenced to the USGS 1:24,000 scale topographic basemap.Hydrologic Units are delineated to nest in a multi-level, hierarchical drainage system with corresponding HUCs, so that as you move from small scale to large scale the HUC digits increase in increments of two. For example, the very largest HUCs have 2 digits, and thus are referred to as HUC 2s, and the very smallest HUCs have 12 digits, and thus are referred to as HUC 12s.Dataset SummaryPhenomenon Mapped: Watersheds in the United States, as delineated by the Watershed Boundary Dataset (WBD)Geographic Extent: Contiguous United States, Alaska, Hawaii, Puerto Rico, Guam, US Virgin Islands, Northern Marianas Islands and American SamoaProjection: Web MercatorUpdate Frequency: AnnualVisible Scale: Visible at all scales, however USGS recommends this dataset should not be used for scales of 1:24,000 or larger.Source: United States Geological Survey (WBD)Data Vintage: January 7, 2025What can you do with this layer?This layer is suitable for both visualization and analysis acrossthe ArcGIS system. This layer can be combined with your data and other layers from the ArcGIS Living Atlas of the World in ArcGIS Online and ArcGIS Pro to create powerful web maps that can be used alone or in a story map or other application. Because this layer is part of the ArcGIS Living Atlas of the World it is easy to add to your map:In ArcGIS Online, you can add this layer to a map by selecting Add then Browse Living Atlas Layers. A window will open. Type "Watershed Boundary Dataset" in the search box and browse to the layer. Select the layer then click Add to Map. In ArcGIS Pro, open a map and select Add Data from the Map Tab. Select Data at the top of the drop down menu. The Add Data dialog box will open on the left side of the box, expand Portal if necessary, then select Living Atlas. Type "Watershed Boundary Dataset" in the search box, browse to the layer then click OK.Questions?Please leave a comment below if you have a question about this layer, and we will get back to you as soon as possible.

Each drainage area is considered a Hydrologic Unit (HU) and is given a Hydrologic Unit Code (HUC) which serves as the unique identifier for the area. HUC 2s, 6s, 8s, 10s, & 12s, define the drainage Regions, Subregions, Basins, Subbasins, Watersheds and Subwatersheds, respectively, across the United States. Their boundaries are defined by hydrologic and topographic criteria that delineate an area of land upstream from a specific point on a river and are determined solely upon science based hydrologic principles, not favoring any administrative boundaries, special projects, or a particular program or agency. The Watershed Boundary Dataset is delineated and georeferenced to the USGS 1:24,000 scale topographic basemap.Hydrologic Units are delineated to nest in a multi-level, hierarchical drainage system with corresponding HUCs, so that as you move from small scale to large scale the HUC digits increase in increments of two. For example, the very largest HUCs have 2 digits, and thus are referred to as HUC 2s, and the very smallest HUCs have 12 digits, and thus are referred to as HUC 12s.Dataset SummaryPhenomenon Mapped: Watersheds in the United States, as delineated by the Watershed Boundary Dataset (WBD)Geographic Extent: Contiguous United States, Alaska, Hawaii, Puerto Rico, Guam, US Virgin Islands, Northern Marianas Islands and American SamoaProjection: Web MercatorUpdate Frequency: AnnualVisible Scale: Visible at all scales, however USGS recommends this dataset should not be used for scales of 1:24,000 or larger.Source: United States Geological Survey (WBD)Data Vintage: January 7, 2025What can you do with this layer?This layer is suitable for both visualization and analysis acrossthe ArcGIS system. This layer can be combined with your data and other layers from the ArcGIS Living Atlas of the World in ArcGIS Online and ArcGIS Pro to create powerful web maps that can be used alone or in a story map or other application. Because this layer is part of the ArcGIS Living Atlas of the World it is easy to add to your map:In ArcGIS Online, you can add this layer to a map by selecting Add then Browse Living Atlas Layers. A window will open. Type "Watershed Boundary Dataset" in the search box and browse to the layer. Select the layer then click Add to Map. In ArcGIS Pro, open a map and select Add Data from the Map Tab. Select Data at the top of the drop down menu. The Add Data dialog box will open on the left side of the box, expand Portal if necessary, then select Living Atlas. Type "Watershed Boundary Dataset" in the search box, browse to the layer then click OK.Questions?Please leave a comment below if you have a question about this layer, and we will get back to you as soon as possible.

Karst is a landscape where the hydrology of surface water systems is intricately connected to groundwater systems through the development of conduits and solutional opening in soluble bedrock, such as limestone, marble, or dolomite. This connectivity can present challenges to preserving water quality and quantity for karst aquifers, as activities that occur in karst areas can often have a direct impact to groundwater quality. Agency personnel responsible for managing karst areas must understand the karst landscapes that drain to springs and caves to properly preserve groundwater quality. Oregon Caves National Monument and Preserve is in Josephine County, Oregon approximately 11 miles east of the community of Cave Junction. The Monument and Preserve protect 4,554 acres of conifer-dominated forests, meadows, streams, and multiple cave systems. From 2021 to 2024, the U.S. Geological Survey along with personnel from Oregon Caves National Monument and Preserve conducted a dye tracing investigation seeking to delineate recharge areas for two karst systems, Oregon Caves and Cave Next Door. Additionally, the study sought to determine if there were any hydrologic connections between these two karst systems. A total of eight dye injections were conducted, delineating a recharge area for each of the two karst systems, confirming hydrologic connections among different streams within the Oregon Caves system, and identifying previously undocumented resurgences for the stream in Oregon Caves. This data release contains shapefiles that relate to dye injection locations, monitoring sites, dye traces, and delineated recharge areas. All files were created in ArcGIS Pro and each shapefile contains associated attributes for the features contained within. Layer files are included with the datasets to match symbology found in figures in the accompanying report. All shapefiles and layer files were created and modified in ArcGIS software. For a full description of the methods to create these files, see Process Steps in "ORCA_Metdata.xml" metadata file.

Each drainage area is considered a Hydrologic Unit (HU) and is given a Hydrologic Unit Code (HUC) which serves as the unique identifier for the area. HUC 2s, 6s, 8s, 10s, & 12s, define the drainage Regions, Subregions, Basins, Subbasins, Watersheds and Subwatersheds, respectively, across the United States. Their boundaries are defined by hydrologic and topographic criteria that delineate an area of land upstream from a specific point on a river and are determined solely upon science based hydrologic principles, not favoring any administrative boundaries, special projects, or a particular program or agency. The Watershed Boundary Dataset is delineated and georeferenced to the USGS 1:24,000 scale topographic basemap.Hydrologic Units are delineated to nest in a multi-level, hierarchical drainage system with corresponding HUCs, so that as you move from small scale to large scale the HUC digits increase in increments of two. For example, the very largest HUCs have 2 digits, and thus are referred to as HUC 2s, and the very smallest HUCs have 12 digits, and thus are referred to as HUC 12s.Dataset SummaryPhenomenon Mapped: Watersheds in the United States, as delineated by the Watershed Boundary Dataset (WBD)Geographic Extent: Contiguous United States, Alaska, Hawaii, Puerto Rico, Guam, US Virgin Islands, Northern Marianas Islands and American SamoaProjection: Web MercatorUpdate Frequency: AnnualVisible Scale: Visible at all scales, however USGS recommends this dataset should not be used for scales of 1:24,000 or larger.Source: United States Geological Survey (WBD)Data Vintage: January 7, 2025What can you do with this layer?This layer is suitable for both visualization and analysis acrossthe ArcGIS system. This layer can be combined with your data and other layers from the ArcGIS Living Atlas of the World in ArcGIS Online and ArcGIS Pro to create powerful web maps that can be used alone or in a story map or other application. Because this layer is part of the ArcGIS Living Atlas of the World it is easy to add to your map:In ArcGIS Online, you can add this layer to a map by selecting Add then Browse Living Atlas Layers. A window will open. Type "Watershed Boundary Dataset" in the search box and browse to the layer. Select the layer then click Add to Map. In ArcGIS Pro, open a map and select Add Data from the Map Tab. Select Data at the top of the drop down menu. The Add Data dialog box will open on the left side of the box, expand Portal if necessary, then select Living Atlas. Type "Watershed Boundary Dataset" in the search box, browse to the layer then click OK.Questions?Please leave a comment below if you have a question about this layer, and we will get back to you as soon as possible.

Each drainage area is considered a Hydrologic Unit (HU) and is given a Hydrologic Unit Code (HUC) which serves as the unique identifier for the area. HUC 2s, 6s, 8s, 10s, & 12s, define the drainage Regions, Subregions, Basins, Subbasins, Watersheds and Subwatersheds, respectively, across the United States. Their boundaries are defined by hydrologic and topographic criteria that delineate an area of land upstream from a specific point on a river and are determined solely upon science based hydrologic principles, not favoring any administrative boundaries, special projects, or a particular program or agency. The Watershed Boundary Dataset is delineated and georeferenced to the USGS 1:24,000 scale topographic basemap.Hydrologic Units are delineated to nest in a multi-level, hierarchical drainage system with corresponding HUCs, so that as you move from small scale to large scale the HUC digits increase in increments of two. For example, the very largest HUCs have 2 digits, and thus are referred to as HUC 2s, and the very smallest HUCs have 12 digits, and thus are referred to as HUC 12s.Dataset SummaryPhenomenon Mapped: Watersheds in the United States, as delineated by the Watershed Boundary Dataset (WBD)Geographic Extent: Contiguous United States, Alaska, Hawaii, Puerto Rico, Guam, US Virgin Islands, Northern Marianas Islands and American SamoaProjection: Web MercatorUpdate Frequency: AnnualVisible Scale: Visible at all scales, however USGS recommends this dataset should not be used for scales of 1:24,000 or larger.Source: United States Geological Survey (WBD)Data Vintage: January 7, 2025What can you do with this layer?This layer is suitable for both visualization and analysis acrossthe ArcGIS system. This layer can be combined with your data and other layers from the ArcGIS Living Atlas of the World in ArcGIS Online and ArcGIS Pro to create powerful web maps that can be used alone or in a story map or other application. Because this layer is part of the ArcGIS Living Atlas of the World it is easy to add to your map:In ArcGIS Online, you can add this layer to a map by selecting Add then Browse Living Atlas Layers. A window will open. Type "subsidence" in the search box and browse to the layer. Select the layer then click Add to Map. In ArcGIS Pro, open a map and select Add Data from the Map Tab. Select Data at the top of the drop down menu. The Add Data dialog box will open on the left side of the box, expand Portal if necessary, then select Living Atlas. Type "subsidence" in the search box, browse to the layer then click OK.Questions?Please leave a comment below if you have a question about this layer, and we will get back to you as soon as possible.

Each drainage area is considered a Hydrologic Unit (HU) and is given a Hydrologic Unit Code (HUC) which serves as the unique identifier for the area. HUC 2s, 6s, 8s, 10s, & 12s, define the drainage Regions, Subregions, Basins, Subbasins, Watersheds and Subwatersheds, respectively, across the United States. Their boundaries are defined by hydrologic and topographic criteria that delineate an area of land upstream from a specific point on a river and are determined solely upon science based hydrologic principles, not favoring any administrative boundaries, special projects, or a particular program or agency. The Watershed Boundary Dataset is delineated and georeferenced to the USGS 1:24,000 scale topographic basemap.Hydrologic Units are delineated to nest in a multi-level, hierarchical drainage system with corresponding HUCs, so that as you move from small scale to large scale the HUC digits increase in increments of two. For example, the very largest HUCs have 2 digits, and thus are referred to as HUC 2s, and the very smallest HUCs have 12 digits, and thus are referred to as HUC 12s.Dataset SummaryPhenomenon Mapped: Watersheds in the United States, as delineated by the Watershed Boundary Dataset (WBD)Geographic Extent: Contiguous United States, Alaska, Hawaii, Puerto Rico, Guam, US Virgin Islands, Northern Marianas Islands and American SamoaProjection: Web MercatorUpdate Frequency: AnnualVisible Scale: Visible at all scales, however USGS recommends this dataset should not be used for scales of 1:24,000 or larger.Source: United States Geological Survey (WBD)Data Vintage: January 7, 2025What can you do with this layer?This layer is suitable for both visualization and analysis acrossthe ArcGIS system. This layer can be combined with your data and other layers from the ArcGIS Living Atlas of the World in ArcGIS Online and ArcGIS Pro to create powerful web maps that can be used alone or in a story map or other application. Because this layer is part of the ArcGIS Living Atlas of the World it is easy to add to your map:In ArcGIS Online, you can add this layer to a map by selecting Add then Browse Living Atlas Layers. A window will open. Type "Watershed Boundary Dataset" in the search box and browse to the layer. Select the layer then click Add to Map. In ArcGIS Pro, open a map and select Add Data from the Map Tab. Select Data at the top of the drop down menu. The Add Data dialog box will open on the left side of the box, expand Portal if necessary, then select Living Atlas. Type "Watershed Boundary Dataset" in the search box, browse to the layer then click OK.

Accurate evaluation of riparian forests depends on precise delineation of both bank to bank (active channel) and single-thread hydrography. Local land use and salmon recovery planners use hydrography as a reliable tool for understanding and managing watershed impacts across the state. Active channel mapping allows practitioners to delineate riparian zones, examine the shading effects of riparian vegetation, map the location, extent, and distribution of anadromous and resident fish as well as locate fish blocking culverts, map protective stream buffers, and accurately inventory existing hydrography (Hyatt et al, 2022).The manual provided in this package describes methods and procedures used to digitize active channel polygons from high resolution elevation data and high-resolution imagery. Methods like this have become necessary, as access to high resolution data has become easier. Included in this method is AC Tools, a Python script-based ArcGIS Pro Toolset that can be used to delineate channel bank and channel island contour lines along river mainstems and larger tributaries. Much of the method involves how to select those contours and create active channel polygons. Methods are also available for download at https://pspwa.box.com/s/3stokaav635odvd8k2dtkcigef5sbkr2Pilot results of this methodology were conducted in Stillaguamish, Queets, and the Entiat River, and are available at the Puget Sound Partnerships Spatial Data Hub.

Active Channel HydrographyThe “active channel” includes the wetted channels of rivers and streams as well as adjacent un-vegetated cobble and gravel bars that are inundated during high flows. In this method, the active channel is analogous to the “bankfull channel” (Leopold and Maddock 1953, Leopold et al 1964, Williams 1978) or the ordinary high-water mark line (OHWM), where the presence and action of waters are “so common and usual, and so long continued in ordinary years as to mark upon the soil or vegetation a character distinct from the abutting upland,”(WAC 220-660-030(111)). In places where this line cannot the delineated the ordinary high water line is delineated along the elevation of the mean annual flood for every three years.

There are many reasons for considering the boundary of the active channel network. A common use for delineating the active channel is to map the inner edge of the riparian zone (eg. Hyatt 2023). Riparian areas are transitional areas between land and aquatic ecosystems that include both lotic and lentic systems (Gregory et al, 1991). These zones can include the surface and subsurface water influences and human induced natural forces, understanding the active channel boundary thereby isn’t just important for managing fish populations and identifying habitat restoration sites, it is also important for land use planning and management.

Each drainage area is considered a Hydrologic Unit (HU) and is given a Hydrologic Unit Code (HUC) which serves as the unique identifier for the area. HUC 2s, 6s, 8s, 10s, & 12s, define the drainage Regions, Subregions, Basins, Subbasins, Watersheds and Subwatersheds, respectively, across the United States. Their boundaries are defined by hydrologic and topographic criteria that delineate an area of land upstream from a specific point on a river and are determined solely upon science based hydrologic principles, not favoring any administrative boundaries, special projects, or a particular program or agency. The Watershed Boundary Dataset is delineated and georeferenced to the USGS 1:24,000 scale topographic basemap.Hydrologic Units are delineated to nest in a multi-level, hierarchical drainage system with corresponding HUCs, so that as you move from small scale to large scale the HUC digits increase in increments of two. For example, the very largest HUCs have 2 digits, and thus are referred to as HUC 2s, and the very smallest HUCs have 12 digits, and thus are referred to as HUC 12s.Dataset SummaryPhenomenon Mapped: Watersheds in the United States, as delineated by the Watershed Boundary Dataset (WBD)Geographic Extent: Contiguous United States, Alaska, Hawaii, Puerto Rico, Guam, US Virgin Islands, Northern Marianas Islands and American SamoaProjection: Web MercatorUpdate Frequency: AnnualVisible Scale: Visible at all scales, however USGS recommends this dataset should not be used for scales of 1:24,000 or larger.Source: United States Geological Survey (WBD)Data Vintage: January 7, 2025What can you do with this layer?This layer is suitable for both visualization and analysis acrossthe ArcGIS system. This layer can be combined with your data and other layers from the ArcGIS Living Atlas of the World in ArcGIS Online and ArcGIS Pro to create powerful web maps that can be used alone or in a story map or other application. Because this layer is part of the ArcGIS Living Atlas of the World it is easy to add to your map:In ArcGIS Online, you can add this layer to a map by selecting Add then Browse Living Atlas Layers. A window will open. Type "Watershed Boundary Dataset" in the search box and browse to the layer. Select the layer then click Add to Map. In ArcGIS Pro, open a map and select Add Data from the Map Tab. Select Data at the top of the drop down menu. The Add Data dialog box will open on the left side of the box, expand Portal if necessary, then select Living Atlas. Type "Watershed Boundary Dataset" in the search box, browse to the layer then click OK.Questions?Please leave a comment below if you have a question about this layer, and we will get back to you as soon as possible.

Source data found here: https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServerEach drainage area is considered a Hydrologic Unit (HU) and is given a Hydrologic Unit Code (HUC) which serves as the unique identifier for the area. HUC 2s, 6s, 8s, 10s, & 12s, define the drainage Regions, Subregions, Basins, Subbasins, Watersheds and Subwatersheds, respectively, across the United States. Their boundaries are defined by hydrologic and topographic criteria that delineate an area of land upstream from a specific point on a river and are determined solely upon science based hydrologic principles, not favoring any administrative boundaries, special projects, or a particular program or agency. The Watershed Boundary Dataset is delineated and georeferenced to the USGS 1:24,000 scale topographic basemap.Hydrologic Units are delineated to nest in a multi-level, hierarchical drainage system with corresponding HUCs, so that as you move from small scale to large scale the HUC digits increase in increments of two. For example, the very largest HUCs have 2 digits, and thus are referred to as HUC 2s, and the very smallest HUCs have 12 digits, and thus are referred to as HUC 12s.Dataset SummaryPhenomenon Mapped: Watersheds in the United States, as delineated by the Watershed Boundary Dataset (WBD)Geographic Extent: Contiguous United States, Alaska, Hawaii, Puerto Rico, Guam, US Virgin Islands, Northern Marianas Islands and American SamoaProjection: Web MercatorUpdate Frequency: AnnualVisible Scale: Visible at all scales, however USGS recommends this dataset should not be used for scales of 1:24,000 or larger.Source: United States Geological SurveyPublication Date: January 7, 2025What can you do with this layer?This layer is suitable for both visualization and analysis acrossthe ArcGIS system. This layer can be combined with your data and other layers from the ArcGIS Living Atlas of the World in ArcGIS Online and ArcGIS Pro to create powerful web maps that can be used alone or in a story map or other application. Because this layer is part of the ArcGIS Living Atlas of the World it is easy to add to your map:In ArcGIS Online, you can add this layer to a map by selecting Add then Browse Living Atlas Layers. A window will open. Type "Watershed Boundary Dataset" in the search box and browse to the layer. Select the layer then click Add to Map. In ArcGIS Pro, open a map and select Add Data from the Map Tab. Select Data at the top of the drop down menu. The Add Data dialog box will open on the left side of the box, expand Portal if necessary, then select Living Atlas. Type "Watershed Boundary Dataset" in the search box, browse to the layer then click OK.

AbstractBuilt up area polygons represent where buildings are clustered together, such as urban areas. Layer can be used for activities such as monitoring urban growth, or responding to natural disasters. The product has been designed for AUSTopo - Australian Digital Topographic Map Series 250k.Built up area polygons designed for the AUSTopo - Australian Digital Topographic Map Series 250k. Feature class attributes include polygon area (in square metres) and feature type (builtup Area).This dataset provides valuable insights into the built environment of towns and cities, and serves as a crucial resource for urban planners, researchers, policymakers, and developers.CurrencyDate modified: 31 August 2023Modification frequency: Not PlannedData extentSpatial extentNorth: -10.15°South: -43.44°East: 153.64°West: 113.42°Temporal extentFrom 1 January 2013 to 1 January 2018Source informationThis dataset is generated from a publicly-available dataset: Bing Building Footprints, using the 'delineate built up area' tool in ArcGIS Pro.More information on the original source dataset can be found here.Catalogue entry: Built Up Areas DatasetLineage statementDataset was generated by using the Bing Building Footprints of Australia (October 2020) dataset as an input. Built up area layer was created using the delineate built up areas tool in ArcGIS Pro in April 2023. This layer was produced as part of the update of AUSTopo - Australian Digital Topographic Map Series 250k.The Digital Atlas of Australia team at Geoscience Australia have projected this dataset from GDA2020 to web mercator to accurately reflect in the web map. Minor changes to symbology have also been made to improve accessibility.The date of extraction 4 SEPTEMBER 2023.Data dictionaryAll layersAttribute nameDescriptionObject IDUnique identifier for the area polygonArea (sq. m)Measured area of the built-up regionFeature TypeAll features in this set are "Builtup Area"SHAPE LengthInternal - length of the polygon perimeterSHAPE AreaInternal - area of the generated polygonContactGeoscience Australia, clientservices@ga.gov.au

Geodatabase of ultramafic (serpentine) substrates in South Coast Ranges, California, USA Ryan O’Dell Natural Resource Specialist Bureau of Land Management Central Coast Field Office Marina, California, USA rodell@blm.gov August 2025 Background and Goals Rock type and soil type have a strong influence on plant species distribution. There are about 250 plant taxa endemic to ultramafic substrate in California (Miller and Safford 2020). Many have small ranges (local endemics) and are rare or endangered. Plant ecologists and conservationists wish to develop Species Distribution Models (SDMs) for ultramafic endemic plant species in GIS. However, there is no existing, continuous, high accuracy geodatabase of ultramafic substrates for most of California. Most ultramafic Species Distribution Models (SDMs) produced in the past 15 years have used the Geologic Map of California (USGS 2010; 1:750,000 scale) and/or Gridded Soil Survey Geographic Database (gSSURGO; NRCS; 1:6,000 scale). Neither of these data sources delineate ultramafic substrates with high enough accuracy for satisfactory SDMs. Polygon lines often do not closely match ultramafic geologic boundaries clearly visible in the high-resolution satellite imagery. Additionally, smaller ultramafic masses, ultramafic landslides, and ultramafic alluvial deposits are either not mapped, or not identified by rock type (e.g. Qls or Qa, only). The goal is to produce a continuous, fine scale (0.1 ha MMU), high accuracy (± 20 m) geodatabase of ultramafic substrates for most of California. The first stage (2020 – 2025) will be to delineate polygons of ultramafic masses, ultramafic landslides, and ultramafic alluvium as accurately as possible. The second stage (2025 - 2030) will be to divide the polygons further and assign attributes based on field observations including - rock_type · serpentinite, 75-100% · peridotite, serpentinized 25 - 75% · peridotite, serpentinized 0 - 25% shear_strength · block, pulverized matrix · block, sheared matrix · block, no matrix soil_series soil_depth · < 10 cm · 10 - 30 cm · 30 cm+ soil_texture · clay · clay-loam · loam · sandy-loam · sand Data sources 1) High resolution satellite imagery from Google Earth – portable basemap server. Airbus; Landsat/Copernicus. https://mt1.google.com/vt/lyrs=s&x={col}&y={row}&z={level} 2) National Geologic Map Database (NGMD). https://ngmdb.usgs.gov/ngmdb/ngmdb_home.html Dibblee Maps (1:24,000 scale) are generally the most detailed and highest accuracy for South Coast Ranges. https://store.aapg.org/ATSResources/product-splash/dibblee.aspx 3) Gridded Soil Survey Geographic Database (gSSURGO). gSSURGO_CA.gdb https://www.nrcs.usda.gov/resources/data-and-reports/gridded-soil-survey-geographic-gssurgo-database Extracting and drawing the polygons 1) Trace ultramafic rock polygons from geologic maps. The National Geologic Map Database (NGMD). I examined the digitized maps to identify those with highest accuracy. For the South Coast Ranges, these tended to be the Dibblee Maps, which are not available for download on NGMD - viewing only. For the Dibblee Maps, I collected screen capture images (JPEG) from the NGMD map viewer, then manually georeferenced them in ArcGIS Pro (GIS). All other maps in NGMD (GeoTiff) were downloaded and opened in GIS. I then manually traced all polygons mapped as ultramafic rock types. 2) Extract ultramafic soil polygons from gSSURGO. I carefully identified all of the map unit key (MUKEY) codes corresponding to soils derived from ultramafic rock and extracted the polygons from gSSURGO. A spreadsheet of these can be found in Figshare – “Ultramafic soils NRCS – CA, OR, WA.” SQLs to extract the polygons from gSSURGO is in “Extract all ultramafic soil polygons from gSSURGO for California, Oregon, and Washington, USA.” 3) Compare ultramafic rock polygon lines to ultramafic soil polygons and high-resolution satellite imagery, and adjust the lines. Ultramafic soil polygons and high-resolution satellite imagery were used to adjust the ultramafic rock polygon lines through consensus of data and visual indicators. Ultramafic rock and soil has a distinctive color, compared to adjacent non-ultramafic rock types. Serpentinite rock has a blue hue. Weathered ultramafic rock (especially peridotite) and soil typically has a substantially redder hue (oxidized iron), than adjacent non-ultramafic rock types. Vegetative cover on ultramafic rock is typically much lower than the adjacent non-ultramafic rock, so both the color of the rock and soil is visible in satellite imagery. The vegetation type (color and patterns) on ultramafic rock also typically contrasts sharply with the surrounding non-ultramafic rock. In South Coast Ranges, the strict ultramafic endemic large woody shrub Quercus durata var. durata appears as a distinctive gray-green color. I used my 20+ years of field observations and knowledge of ultramafic areas from throughout California to manually adjust the ultramafic polygons based on rock, soil, and vegetation color patterns in the high resolution satellite imagery. I also carefully examined the satellite imagery and delineated small ultramafic masses, ultramafic landslides, and ultramafic alluvial deposits not mapped (represented) in the geologic maps or soil surveys. 4) Follow-up field observations and reexamination of polygons in GIS. Most of the ultramafic polygons for South Coast Ranges were drawn in 2020 and 2021. I conducted additional field work 2021 – 2025 (as checks), reexamined polygons in GIS, and continued to improve polygon line accuracy.

This shapefile displays the watershed boundaries for NEON's aquatic wadeable and non-wadeable stream and lake sites. The watershed boundary defines the perimeter of drainage areas formed by the terrain and other landscape characteristics. The pour point was selected nearest the downstream most sensor set, primarily NEON’s S2 sensor in wadeable streams, S1 or stream gauge in non-wadeable rivers, and the outlet sensor in lakes. For most of the sites NEON's 1 meter Elevation-LiDAR Digital Terrain Model (DTM) was used to derive the watersheds. In cases where NEON data did not provide complete watershed coverage, a 1/3 arc-second (10 meter) resolution Digital Elevation Model (DEM) raster, available from the U.S. Geological Survey (USGS) website, was utilized to provide full coverage of the watershed extent. A mosaic dataset was created to combine individual DTM or DEM tiles, and a local projection defined for the dataset. ArcGIS Pro software with the ArcHydro Tools [for] Pro were used to model and delineate the watershed. Attribute Table Information:DomainNum:NEON ecoclimatic domain number. DomainName: NEON ecoclimatic domain name.SiteName: NEON aquatic site name.SiteID: NEON four character site ID for the aquatic site.SiteType:Type of NEON site (e.g. core aquatic or relocatable aquatic).Science: Identifies the primary science theme as they relate to the NEON Grand Challenges (AD[01]) and if the aquatic site is a wadeable or non-wadeable stream, or lake.StateID: The 2 letter abbreviation for the state where the watershed is located.UTM_Zone: The local projected coordinate system for the aquatic site and model processing.WSAreaKm2: Watershed area in kilometers squared for watersheds derived from NEON’s 1 meter Elevation-LiDAR dataset.Source: States if the watershed was not derived from NEON data, these sites are supplemented with the 10 meter National Elevation Dataset.Area_NED: Watershed area in kilometers squared for sites where the watershed was derived from the 10 meter National Elevation Dataset.AOPLiDAR: Name of the Elevation-LiDAR DTM tile from the NEON data portal, includes site ID, year, and month the data was collected.AOP_Flight: Identifies the NEON AOP Flight Boundaries layer showing the extent and priority of airborne acquisition. AOPCoverag: Identifies percent coverage of the NEON AOP flight box over the aquatic watershed.TIS_Dist: Distance in kilometers from the aquatic site pour point to the corresponding terrestrial tower site.TIS_Bear: Bearing in degrees from the aquatic site pour point to the corresponding terrestrial tower site.TIS_WS: States if the corresponding terrestrial tower is within the aquatic watershed.HUC12Name: Name of the Hydrologic Unit Code with twelve digits based on the prominent water or physical feature(s) within the unit. Naming follows the conventions and rules outlined by the Geographic Names Information System (GNIS) order of priority and if the dominant feature is named in the HU10, the HU12 retains the twelve digit code as the name. HUC12: Hydrologic Unit Code with twelve digits based on the sixth-level (subwatershed) classification designated by the United States Geological Survey. NLCD_(number): Percentage of land cover classifications within the watershed from the National Land Cover Dataset (NLCD) (Table 2). NRCS_(Soil abbreviations): Percentage of soil classifications within the watershed from the Natural Resources Conservation Service (NRCS) (Table 3).