The Great Smoky Mountains National Park Hydrology dataset is a value-added attribution of data produced by Great Smoky Mountains National Park and published by the USGS NHD. Not to be confused with the USGS NHD Plus Dataset, the park has published these data as an interim while the NHD Plus "catches up" with recently-updated NHD Stream Data within the park footprint. These data have been attributed in the following way: Strahler Stream Order: In the Strahler method, all links without any tributaries are assigned an order of 1 and are referred to as first order. The stream order increases when streams of the same order intersect. Therefore, the intersection of two first-order links will create a second-order link, the intersection of two second-order links will create a third-order link, and so on. The intersection of two links of different orders, however, will not result in an increase in order. For example, the intersection of a first-order and second-order link will not create a third-order link but will retain the order of the highest ordered link. If the node is a leaf (has no children), its Strahler number is one. If the node has one child with Strahler number i, and all other children have Strahler numbers less than i, then the Strahler number of the node is i again. If the node has two or more children with Strahler number i, and no children with greater number, then the Strahler number of the node is i + 1. The Strahler number of a tree is the number of its root node. Algorithmically, these numbers may be assigned by performing a depth-first search and assigning each node's number in postorder. The same numbers may also be generated via a pruning process in which the tree is simplified in a sequence of stages, where in each stage one removes all leaf nodes and all of the paths of degree-one nodes leading to leaves: the Strahler number of a node is the stage at which it would be removed by this process, and the Strahler number of a tree is the number of stages required to remove all of its nodes. Another equivalent definition of the Strahler number of a tree is that it is the height of the largest complete binary tree that can be homeomorphically embedded into the given tree; the Strahler number of a node in a tree is similarly the height of the largest complete binary tree that can be embedded below that node. Any node with Strahler number i must have at least two descendants with Strahler number i − 1, at least four descendants with Strahler number i − 2, etc., and at least 2i − 1 leaf descendants. Therefore, in a tree with n nodes, the largest possible Strahler number is log2 n. However, unless the tree forms a complete binary tree its Strahler number will be less than this bound. In an n-node binary tree, chosen uniformly at random among all possible binary trees, the expected index of the root is with high probability very close to log4. Sinuosity: A river’s sinuosity is its tendency to move back and forth across its floodplain, in an S-shaped pattern, over time. As the stream meanders across the flood plain, it may leave behind scars of where the river channel once was. A stream that doesn't meander at all has a sinuosity of 1. The more meanders in a stream, the closer the sinuosity value will get to 0. For single-thread stream channels, the sinuosity index is calculated for each reach using its two endpoints (Upstream point A, Downstream point B). The ratio of the sinuous length tho the straight-line distance is Channel Sinuosity value for the reach. The sinuous length is measured down the centerline of the channel. Divide the sinuous length by the straight-line distance between the same two points. Sinuosity values range from 1 to 4 (or so). A completely straight channel will have a sinuosity of 1. Channels with ratios ~1.5 are called sinuous channels. Channels with higher ratios are called meandering channels. Values are commonly reported to two decimal places, but there’s no firm rule. This is a very large

This page is meant to act as an archival repository for previous versions of the statewide National Hydrography Dataset (NHD) which includes the Watershed Boundary Dataset (WBD) released by USGS. All data are presented in their original, unmodified format as downloaded from USGS. Be aware that the data do not come with a geometric network; directions for building the geometric network can be found in the text file on this resource page called "How to Create NHD Network".

This page is meant to act as an archival repository for previous versions of the statewide National Hydrography Dataset (NHD) which includes the Watershed Boundary Dataset (WBD) released by USGS. All data are presented in their original, unmodified format as downloaded from USGS. Be aware that the data do not come with a geometric network; directions for building the geometric network can be found in the text file on this resource page called "How to Create NHD Network".

U.S. Geological Survey, Department of the Interior - The annual Watershed Boundary Dataset (WBD) stewardship plan is to maintain watershed boundary data through usage of WBD edit tools over the United States and its territories. WBD for the Nation has been collected and is now in maintenance mode. Interested parties who wish to become a stewardship partner with the USGS in FY20 or in future years should contact a USGS Geospatial Liaison - https://www.usgs.gov/core-science-systems/ngp/user-engagement-office. To find out more about watershed boundary stewardship go to https://www.usgs.gov/core-science-systems/ngp/national-hydrography/watershed-boundary-dataset

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. High resolution NHD 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.) Like the 1:100,000-scale NHD, high resolution NHD contains reach codes for networked features and isolated lakes, flow direction, names, stream level, and centerline representations for areal water bodies. Reaches are also defined to represent 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 set out by the Federal Geographic Data Committee.

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. High resolution NHD 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.) Like the 1:100,000-scale NHD, high resolution NHD contains reach codes for networked features and isolated lakes, flow direction, names, stream level, and centerline representations for areal water bodies. Reaches are also defined to represent 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 set out by the Federal Geographic Data Committee.

This data package was created 2025-04-22 18:31:25 by NPSTORET and includes selected project, location, and result data. Data contained in the Great Smoky Mountains National Park NPSTORET back-end file (GRSM_NPSTORET_BE_20250409.ACCDB) were filtered to include: Organization: - GRSM: Great Smoky Mountains National Park Project: - GRSM_WQ: GRSM Parkwide Water Quality Survey Station: - Include Trip QC And All Station Visit Results Value Status: - Accepted or Certified (exported as Final) or Final The data package is organized into five data tables: - Projects.csv - describes the purpose and background of the monitoring efforts - Locations.csv - documents the attributes of the monitoring locations/stations - Results.csv - contains the field measurements, observations, and/or lab analyses for each sample/event/data grouping - HUC.csv - enumerates the domain of allowed values for 8-digit and 12-digit hydrologic unit codes utilized by the Locations data table - Characteristics.csv - enumerates the domain of characteristics available in NPSTORET to identify what was sampled, measured or observed in Results Period of record for filtered data is 1993-10-01 to 2024-11-19. This data package is a snapshot in time of one National Park Service project. The most current data for this project, which may be more or less extensive than that in this data package, can be found on the Water Quality Portal at: https://www.waterqualitydata.us/data/Result/search?project=GRSM_WQ&mimeType=csv&zip=yes&dataProfile=biological&providers=STORET

This data package was created 2024-10-17 16:52:40 by NPSTORET and includes selected project, location, and result data. Data contained in the Great Smoky Mountains National Park NPSTORET back-end file (GRSM_NPSTORET_BE_20240510_20240510_1245.ACCDB) were filtered to include: Organization: - GRSM: Great Smoky Mountains National Park Project: - GRSM_WQ: GRSM Parkwide Water Quality Survey Station: - Include Trip QC And All Station Visit Results Value Status: - Accepted or Certified (exported as Final) or Final The data package is organized into five data tables: - Projects.csv - describes the purpose and background of the monitoring efforts - Locations.csv - documents the attributes of the monitoring locations/stations - Results.csv - contains the field measurements, observations, and/or lab analyses for each sample/event/data grouping - HUC.csv - enumerates the domain of allowed values for 8-digit and 12-digit hydrologic unit codes utilized by the Locations data table - Characteristics.csv - enumerates the domain of characteristics available in NPSTORET to identify what was sampled, measured or observed in Results Period of record for filtered data is 1993-10-01 to 2023-11-20. This data package is a snapshot in time of one National Park Service project. The most current data for this project, which may be more or less extensive than that in this data package, can be found on the Water Quality Portal at: https://www.waterqualitydata.us/data/Result/search?project=GRSM_WQ&mimeType=csv&zip=yes&dataProfile=biological&providers=STORET

This layer is extracted from The High Resolution National Hydrography Dataset Plus (NHDPlus HR). This is an integrated set of geospatial data layers, including the best available National Hydrography Dataset (NHD), the 10-meter 3D Elevation Program Digital Elevation Model (3DEP DEM), and the National Watershed Boundary Dataset (WBD). The NHDPlus HR combines the NHD, 3DEP DEMs, and WBD to create a stream network with linear referencing, feature naming, "value added attributes" (VAAs), elevation-derived catchments, and other features for hydrologic data analysis.

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.