The "Map Image Layer - Watershed Boundaries" is the Map Image Layer of Watershed Boundaries. It has been designed specifically for use in ArcGIS Online (and will not directly work in ArcMap or ArcPro). This data has been modified from the original source data to serve a specific business purpose. This data is for cartographic purposes only.The Watershed Boundaries Data Group contains the following layers: DNR Catchments (MnDNR)HUC 12 Boundaries (USGS)HUC 12 IWM Group Boundaries (MPCA)HUC 10 Boundaries (USGS)HUC 8 Boundaries (USGS): HUC 8s represent part or all of a surface drainage basin, a combination of drainage basins, or a distinct hydrologic feature. There are 80 HUC 2s in Minnesota. (i.e. Zumbro (07040004))HUC 6 Boundaries (USGS): HUC 6s are areas which divide the subregions into more than 350 hydrologic accounting units. Minnesota has 17 of the nations hydrologic accounting units: Northwestern Lake Superior (040101), St. Louis (040102), Southwestern Lake Superior (040103), Mississippi Headwaters (070101), Upper Mississippi-Crow-Rum (070102), Minnesota (070200), St. Croix (070300), Upper Mississippi-Black-Root (070400), Upper Mississippi-Maquoketa-Plum (070600), Upper Mississippi-Skunk-Wapsipinicon (070801), Iowa (070802), Des Moines (071000), Upper Red (090201), Lower Red (090203), Rainy (090300), Big Sioux (101702), Missouri-Little Sioux (102300).HUC 4 Boundaries (USGS): HUC 4s are geographic subregions which are drained by a river system, a reach of river and its tributaries in that reach, a closed basin, or a group of streams forming a coastal drainage areas. Minnesota has 12 of the nations 222 subregions: Western Lake Superior (0401), Mississippi Headwaters (0701), Minnesota (0702), St. Croix (0703), Upper Mississippi-Black-Root (0704), Upper Mississippi-Maquoketa-Plum (0706), Upper Mississippi-Iowa-Skunk-Wapsipinicon (0708), Des Moines (0710), Red (0902), Rainy (0903), Missouri-Big Sioux (1017), Missouri-Little Sioux (1023).HUC 2 Boundaries (USGS): HUC 2s are geographic regions which contain the drainage of a major river or a series of rivers. Minnesota has 4 of the nations 21 regions: Great Lakes (R04), Upper Mississippi (R07), Souris-Red-Rainy (R09), and Missouri (R10).These datasets have not been optimized for fast display (but rather they maintain their original shape/precision), therefore it is recommend that filtering is used to show only the features of interest. For more information about using filters please see "Work with map layers: Apply Filters": https://doc.arcgis.com/en/arcgis-online/create-maps/apply-filters.htmFor additional information about the Watershed Boundary Dataset please see:United States Geological Survey Water-Supply Paper 2294: https://pubs.usgs.gov/wsp/wsp2294/Hydrologic Units, The National Atlas of the United State of America: https://pubs.usgs.gov/gip/hydrologic_units/pdf/hydrologic_units.pdfNational Hydrography Dataset, Watershed Boundary Dataset: https://www.usgs.gov/core-science-systems/ngp/national-hydrography/watershed-boundary-dataset

The Watershed Boundary Dataset (WBD) is a comprehensive aggregated collection of hydrologic unit data consistent with the national criteria for delineation and resolution. It defines the areal extent of surface water drainage to a point except in coastal or lake front areas where there could be multiple outlets as stated by the "Federal Standards and Procedures for the National Watershed Boundary Dataset (WBD)" "Standard" (https://pubs.usgs.gov/tm/11/a3/). Watershed boundaries are determined solely upon science-based hydrologic principles, not favoring any administrative boundaries or special projects, nor particular program or agency. This dataset represents the hydrologic unit boundaries to the 12-digit for the entire United States. Some areas may also include additional subdivisions representing the 14- and 16-digit hydrologic unit (HU). At a minimum, the HUs are delineated at 1:24,000-scale in the conterminous United States, 1:25,000-scale in Hawaii, Pacific basin and the Caribbean, and 1:63,360-scale in Alaska, meeting the National Map Accuracy Standards (NMAS). Higher resolution boundaries are being developed where partners and data exist and will be incorporated back into the WBD. WBD data are delivered as a dataset of polygons and corresponding lines that define the boundary of the polygon. WBD polygon attributes include hydrologic unit codes (HUC), size (in the form of acres and square kilometers), name, downstream hydrologic unit code, type of watershed, non-contributing areas, and flow modifications. The HUC describes where the unit is in the country and the level of the unit. WBD line attributes contain the highest level of hydrologic unit for each boundary, line source information and flow modifications. For additional information on NHD, go to https://www.usgs.gov/national-hydrography.

This cartographic quality series of 1:1 000 000 scale colour maps cover the provincial extent of Alberta. The primary provincial base map displays the Alberta Township System (ATS), major hydrographic features, municipalities, major roads, railways and select geoadministrative features (parks, reserves, etc.). In addition to the primary provincial base map, this series includes various themes that overlay the primary base map. The update of this map series is based on the provincial Base Features Access Update Program that has an approximate 5 year update cycle. Each individual map sheet is provided in Adobe .pdf format. The Hydrologic Unit Code (HUC) Watersheds of Alberta represents a collection of five nested hierarchically structured drainage basin feature classes that have been created using the Hydrologic Unit Code system of classification developed by the United States Geological Survey (USGS) with accommodation to reflect the pre-existing Canadian classification system. The HUC Watersheds of Alberta consist of successively smaller hydrologic units that nest within larger hydrologic units, resulting in a hierarchical grouping of alphanumerically-coded watersheds feature classes. There are currently individual feature classes for HUC 2 (coarsest level), HUC 4, HUC 6, HUC 8 and HUC 10 (finest level). This Georeferenced PDF map features HUC 4 and HUC 6.

This data is the latest (Version 6) national hydrologic unit (HU) boundaries at levels 1-6 for Virginia developed and maintained by the Virginia Department of Conservation and Recreation. They have been created in compliance with the most recent published federal standards for delineation of hydrologic units and contain national WBD HU model changes made since that time up to the publication date. The Virginia NWBD schemas include variations from the national WBD schemas. This dataset covers the whole state and is seamless with the WBD products of surrounding states at the time of publication and was developed as part of a seamless hydrologic unit product for the nation at the sixth level to be used for more detailed watershed planning work in the state. This becomes the official statewide sixth level hydrologic unit delineation for Virginia.

Overall Mean Risk summarized by 6th Level Watershed is the product of the likelihood and consequence of wildfire on all mapped highly valued resources and assets combined: People and property, critical infrastructure and surface drinking water intakes. This dataset considers the likelihood of wildfire >250 acres (likelihood of burning), the susceptibility of resources and assets to wildfire of different intensities, and the likelihood of those intensities.  Be aware that conditions vary widely with local topography, fuels, and weather, especially local winds. In all areas, under warm, dry, windy, and drought conditions, expect higher likelihood of fire starts, higher flame lengths/fire intensities, more ember activity, a wildfire more difficult to control, and more severe fire effects and impacts. 5 Categories; Low 0-40th Moderate 40-70th High 70-90th Very High 90-95th Extreme - >95th Water and Non-Burnable Low: Wildfire risk is low to all mapped resources and assets combined: People and property, critical infrastructure and surface drinking water intakes. Low represents the 0 to 40th percentile of values across the landscape. Moderate: Wildfire risk is moderate to all mapped resources and assets combined: People and property, critical infrastructure and surface drinking water intakes. Moderate represents the 40th to 70th percentile of values across the landscape. High: Wildfire risk is high to all mapped resources and assets combined: People and property, critical infrastructure and surface drinking water intakes. High represents the 70th to 90th percentile of values across the landscape. Very High: Wildfire risk is very high to all mapped resources and assets combined: People and property, critical infrastructure and surface drinking water intakes. Very High represents the top 90th to 95th percent of values across the landscape. Extreme: Wildfire risk is Extreme to all mapped resources and assets combined: People and property, critical infrastructure and surface drinking water intakes. Very High represents the top >95th percent of values across the landscape.

This resource contains a shapefile of HUC-8 (eight digit Hydrologic Unit Codes) for the Continental United States (CONUS).

The Watershed Boundary Dataset (WBD) is a comprehensive aggregated collection of hydrologic unit data consistent with the national criteria for delineation and resolution. It defines the areal extent of surface water drainage to a point except in coastal or lake front areas where there could be multiple outlets as stated by the "Federal Standards and Procedures for the National Watershed Boundary Dataset (WBD)" “Standard” (http://pubs.usgs.gov/tm/11/a3/). Watershed boundaries are determined solely upon science-based hydrologic principles, not favoring any administrative boundaries or special projects, nor particular program or agency. This dataset represents the hydrologic unit boundaries to the 12-digit (6th level) for the entire United States. Some areas may also include additional subdivisions representing the 14- and 16-digit hydrologic unit (HU). At a minimum, the HUs are delineated at 1:24,000-scale in the conterminous United States, 1:25,000-scale in Hawaii, Pacific basin and the Caribbean, and 1:63,360-scale in Alaska, meeting the National Map Accuracy Standards (NMAS). Higher resolution boundaries are being developed where partners and data exist and will be incorporated back into the WBD. WBD data are delivered as a dataset of polygons and corresponding lines that define the boundary of the polygon. WBD polygon attributes include hydrologic unit codes (HUC), size (in the form of acres and square kilometers), name, downstream hydrologic unit code, type of watershed, non-contributing areas, and flow modifications. The HUC describes where the unit is in the country and the level of the unit. WBD line attributes contain the highest level of hydrologic unit for each boundary, line source information and flow modifications.

The National Hydrography Dataset (NHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. NHD data was originally developed at 1:100,000-scale and exists at that scale for the whole country. This high-resolution NHD, generally developed at 1:24,000/1:12,000 scale, adds detail to the original 1:100,000-scale NHD. (Data for Alaska, Puerto Rico and the Virgin Islands was developed at high-resolution, not 1:100,000 scale.) Local resolution NHD is being developed where partners and data exist. The NHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water bodies. Reaches are also defined on waterbodies and the approximate shorelines of the Great Lakes, the Atlantic and Pacific Oceans and the Gulf of Mexico. The NHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee.

This EnviroAtlas dataset shows the annual average potential wind energy resource in kilowatt hours per square meter per day for each 12-digit Hydrologic Unit (HUC). It was produced using data from the National Renewable Energy Laboratory (NREL). These estimates represent wind resources at a 10 meter height above surface. 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. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. 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).

Wake County is split between two River Basins (6-digit Hydrologic Unit Code), the Cape Fear River Basin and Neuse River Basins. River basins are determined by the US Geological Survey (USGS). USGS delineates drainage areas at 6 different levels all nesting within each other. These levels start at a regional scale and are given a 2-digit Hydrologic Unit Code (HUC). Two digits are added to the code at each level as it progresses to a smaller drainage area. River basins are at the third level and designated with a 6-digit HUC. Additional information about USGS's WDB can be found at this link.If you would like to find out more about River Basins across the state of NC, visit the Find Your HUC website.

This resource contains medium-resolution (1:100k) National Hydrography Dataset (NHDPlus) [1] map data for a region of 39 Hydrologic Unit Code (HUC) 6-digit (HUC6) basins around the Hurricane Harvey impact zone across Texas, Louisiana, Mississippi and Arkansas. This includes 5978 subwatersheds, 190,192 catchments, and 192,267 flowlines.

USGS active stream gages (924) were downloaded from the USGS National Water Information System (NWIS) [2] and augmented with each gage's HUC2, HUC4, HUC6, HUC8, HUC10 & HUC12 basin identifiers, and COMID of the NHD stream reach for the containing catchment. This allows the user to easily aggregate gages by various watershed boundaries.

NOAA Advanced Hydrologic Prediction System (AHPS) [3] has 362 river forecast points in the Harvey study area. Many of these are co-located with USGS NWIS gages to leverage authoritative observation data.

A shapefile of Texas dams (7290) was directly received from the Texas Commission for Environmental Quality (TCEQ) [4]. They suggest if you have any questions about data, to make an Open Records Request [5].

References [1] NHDPlus Version 2 [http://www.horizon-systems.com/NHDPlus/V2NationalData.php] [2] USGS NWIS [https://waterdata.usgs.gov/nwis] [3] NOAA AHPS [https://water.weather.gov/ahps/forecasts.php] [4] TCEQ Data and Records [https://www.tceq.texas.gov/agency/data] [5] TCEQ Open Records Request [https://www.tceq.texas.gov/agency/data/records-services/reqinfo.html]

The Geographic Information Retrieval and Analysis System (GIRAS) was developed in the mid 70s to put into digital form a number of data layers which were of interest to the USGS. One of these data layers was the Hydrologic Units. The map is based on the Hydrologic Unit Maps published by the U.S. Geological Survey Office of Water Data Coordination, together with the list descriptions and name of region, subregion, accounting units, and cataloging unit. The hydrologic units are encoded with an eight- digit number that indicates the hydrologic region (first two digits), hydrologic subregion (second two digits), accounting unit (third two digits), and cataloging unit (fourth two digits). The data produced by GIRAS was originally collected at a scale of 1:250,000. This data set is a modification for Wyoming of the original United States HUC data produced by the USGS. The primary modifications made in this data set by the Wyoming Water Resources Center include 1) removal of hydrologic units that do not drain witi Wyoming and 2) modification of the hydrologic unit boundaries to better encompass streams and lakes represented in the 1:100,000 scale Digital Line Graph (DLG) of surficial hydrography. The HUC boundaries have not been "clipped" to the Wyoming border, in order to maintain the natural boundaries of the units. This metadata has also been altered from original USGS metadata to be more specific for Wyoming.

The Watershed Boundary Dataset (WBD) from The National Map (TNM) defines the perimeter of drainage areas formed by the terrain and other landscape characteristics. The drainage areas are nested within each other so that a large drainage area, such as the Sacramento River, will be composed of multiple smaller drainage areas, such as the Feather River. Each of these smaller areas can further be subdivided into smaller and smaller drainage areas. The WBD uses six different levels in this hierarchy, with the smallest averaging about 30,000 acres. The WBD is made up of polygons nested into six levels of data respectively defined by Regions, Subregions, Basins, Subbasins, Watersheds, and Subwatersheds. For additional information on the WBD, go to https://www.usgs.gov/core-science-systems/ngp/national-hydrography/watershed-boundary-dataset. DWR is the steward for NHD and WBD in California. We work with other organizations to edit and improve NHD and WBD, using the business rules for California. California's WBD improvements are sent to USGS for certification and incorporation to the national geodatabase. The certified WBD is included within the National Hydrography Dataset downloadable file geodatabase, and is also available in shapefile format and as web map services accessible from the USGS website. (https://www.usgs.gov/core-science-systems/ngp/national-hydrography/access-national-hydrography-products)

Watershed boundaries for the Chicago Wilderness region. Includes boundaries for Hydrologic Unit Codes (HUC) 6, 8, 10, and 12 digits. Source: https://pubs.usgs.gov/tm/11/a3/

WBDHU6: This geospatial dataset represents the 3rd level (6-digit) hydrologic unit boundaries of the Watershed Boundary Dataset (WBD) layer for Washington. It was created by dissolving boundaries from the finer resolution hydrologic units to create these broader boundaries. See metadata for the wbd_wa_poly feature class for a more complete description of the WBD. USGS Federal Standards and Procedures for the National Watershed Boundary Dataset (WBD) located here: http://pubs.usgs.gov/tm/11/a3/pdf/tm11-a3.pdf

Percent reduction is based on the number of native species determined to be present as of 2015, compared with historical numbers documented prior to 1970. Data are displayed by 6-digit hydrologic unit code (HUC-6) watershed. A species is considered "present" if there is at least one record of its presence in any 8-digit HUC within the 6-digit HUC. This indicator presents a summary of data available from the NatureServe Explorer database (https://www.natureserve.org/conservation-tools/data-maps-tools/natureserve-explorer). The identity and status (current vs. historical) of all native fish species recorded in each 8-digit HUC are available from this database, along with species-by-species distribution maps at the 8-digit HUC level. Analyses based on these data have previously been reported in Master et al. (1998, 2003) and Stein et al. (2000). Data were provided by NatureServe.

This EnviroAtlas dataset includes the summed below ground live tree root dry biomass estimate by 12-digit Hydrologic Unit (HUC) in metric tons (megagrams) from the 2000 National Biomass and Carbon Dataset (Version 2.0) developed by the Woods Hole Research Center, released in October, 2012. 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. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. 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 resource contains medium-resolution (1:100k) National Hydrography Dataset (NHDPlus) [1] map data for a region of 23 Hydrologic Unit Code (HUC) 6-digit (HUC6) basins around the Hurricane Irma impact zone across Florida, Georgia, and the Carolinas. This includes 5,236 subwatersheds, 217,308 catchments, and 220,418 flowlines.

State and county boundaries were obtained from the Esri Living Atlas [2].

USGS active stream gages can be downloaded from the USGS National Water Information System (NWIS) [3], or visualized at the USGS WaterWatch site [4]. NOAA Advanced Hydrologic Prediction System (AHPS) river forecast points can be downloaded as well [5]. Many of these are co-located with USGS NWIS gages to leverage authoritative observation data.

References [1] NHDPlus Version 2 [http://www.horizon-systems.com/NHDPlus/V2NationalData.php] [2] Esri Living Atlas [https://livingatlas.arcgis.com] [3] USGS NWIS [https://waterdata.usgs.gov/nwis] [4] USGS WaterWatch [https://waterwatch.usgs.gov] [5] NOAA AHPS [https://water.weather.gov/ahps/forecasts.php]

A TMDL (Total Maximum Daily Load is a scientific determination of the maximum amount of a given pollutant that a surface water can absorb and still meet the water quality standards that protect its designated uses including recreation, human health, and aquatic life. Water bodies that do not meet water quality standards are identified as 'impaired' for the particular pollutants of concern — nutrients, bacteria, mercury, etc. — and TMDLs must be developed, adopted and implemented for those pollutants to reduce pollutants and restore the water body so that designated uses are attained. The threshold limits on pollutants in surface waters — Florida's surface water quality standards on which TMDLs are based —are set forth primarily in rules 62-302 and 62-303, Florida Administrative Code (FAC), and the associated table of water quality criteria. Adopted TMDL rules are included in Chapter 62-304, FAC. The data layer depicts the hydrologic basins where the State of Florida has proposed future development of TMDLs through 2022. These basins are based on the Hydrologic Unit Code (HUC) watersheds that are delineated by USGS using a nationwide system based on surface hydrologic features. This system divides the country into 21 regions (2-digit), 222 subregions (4-digit), 370 basins (6-digit), 2,270 subbasins (8-digit), approximately 20,000 watersheds (10-digit), and approximately 100,000 subwatersheds (12-digit). The HUC basins shown here are at the 8-digit level.

This data product is related to a journal article that has been accepted for publication in Geophysical Research Letters (July, 2022).

This resources includes the Python scripts to calculate Index of Connectivity maps and MATLAB scripts for generating the plots used in the manuscript. This resource also includes the following Word/PDF files: (1) the text file of the manuscript, (2) the figures file, and (3) the supplemental information file. These files describe the process the authors undertook to create a structural connectivity map of the contiguous United States (CONUS). The exact methods are described in the text file. To download connectivity raster maps, visit the following link: https://apps.cuahsi.org/connectivity-map.

The plain language summary for the manuscript is shown below:

Hillslopes are critical landscape features that intercept, store, and route water, from its source as rainfall to its fate as river discharge. The strength of this routing is a function of climatic and tectonic forces, but their relative importance to hillslope connectivity is uncertain. We simulated the Index of Connectivity, a topographic analogue for structural connectivity, for 75 billion locations in CONUS, across a range of climatic and tectonic settings. At the CONUS-scale, we found that hillslope connectivity is largely driven by tectonic forces, including uplift and seismic activity, and that highly connected hillslopes are more susceptible to landslides while poorly connected hillslopes promote wetland development. We provide a web data portal to serve as a tool for stakeholders to visualize and leverage structural connectivity data in their respective study areas.

Percent reduction is based on the number of native species determined to be present as of 2015, compared with historical numbers documented prior to 1970. Data are displayed by 6-digit hydrologic unit code (HUC-6) watershed. A species is considered "present" if there is at least one record of its presence in any 8-digit HUC within the 6-digit HUC. This indicator presents a summary of data available from the NatureServe Explorer database (https://www.natureserve.org/conservation-tools/data-maps-tools/natureserve-explorer). The identity and status (current vs. historical) of all native fish species recorded in each 8-digit HUC are available from this database, along with species-by-species distribution maps at the 8-digit HUC level. Analyses based on these data have previously been reported in Master et al. (1998, 2003) and Stein et al. (2000). Data were provided by NatureServe.