|Originator||U.S. Geological Survey (USGS) in cooperation with U. S. Environmental Protection Agency and other state and local partners.|
|Title||National Hydrography Dataset (NHD) - High-Resolution - Minnesota|
|Abstract||The National Hydrography Dataset (NHD) is the surface-water component of The National Map. The NHD is a comprehensive set of digital spatial data that represents the surface water of the United States using common features such as lakes, ponds, streams, rivers, canals, stream gages, and dams. Polygons are used to represent area features such as lakes, ponds, and rivers; lines are used to represent linear features such as streams and smaller rivers; and points are used to represent point features such as stream gages and dams. Lines also are used to show the water flow through area features such as the flow of water through a lake. The combination of lines is used to create a network of water and transported material flow to allow users of the data to trace movement in downstream and upstream directions. The Watershed Boundary Dataset (WBD) is a companion dataset to the NHD. It 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 Upper Mississippi River, will be composed of multiple smaller drainage areas, such as the Minnesota 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.|
|Purpose||These data are designed to be used in general mapping and in the analysis of surface-water systems using geographic information system (GIS) technology. In mapping, the NHD is used with other data themes such as elevation, boundaries, and transportation to produce general reference maps. These maps often serve as base maps for special purpose mapping. A geologic map, for example, may show base map information such as hydrography as a reference. In the analysis of surface water, scientists use the NHD and WBD by applying GIS technology. This application takes advantage of a rich set of embedded attributes that can be processed by a computer system to generate specialized information. This information then can be portrayed in customized maps to better understand the results. These analyses of hydrography are possible largely because the NHD contains the flow-direction network, and uses an addressing system to link specific information about the water from other related databases such as water discharge, water quality, and fish population. Using the basic water features, flow network, linked information, and other characteristics, it is possible to study cause and effect relationships, such as how a source of poor water quality upstream might affect a fish population downstream. The WBD plays an important role in this analysis by outlining the area on the landscape that drains into the flow network defined by the NHD. These data also are linked to the Geographic Names Information System to provide accurate hydrography names. The NHD and WBD often are used as a data source to specific applications such as StreamStats, ICWater, or ArcHydro.|
|Time Period of Content Date||04/13/2015|
|Currentness Reference||publication date; data capture represents the period 1/1/1964 - Present|
|Maintenance and Update Frequency||As needed|
|Spatial Extent of Data||Minnesota, statewide. 80 subbasins (WBD HU_8 units covering the state of Minnesota). Note that NHD is a nationwide dataset - this distribution is for Minnesota's area of interest only. Since the NHD state extract covers full HUC-8 areas (subasins), there is some overlap of data into adjacent states and provinces.|
|Place Keywords||Conterminous United States|
|Theme Keyword Thesaurus||ISO 19115 Topic Category|
|Use Constraints||None. Acknowledgment of the originating agencies would be appreciated in products derived from these data.|
|Contact Person Information||Jeffrey D. Simley,
U.S. Geological Survey
Box 25046, MS 510 Denver Federal Center
Denver, CO 80225-0046
Phone: (303) 202-4131
Fax: (303) 202-4504
|Browse Graphic||None available|
|Associated Data Sets|| National Hydrography Dataset (NHD) main site (includes WBD):
A state subset of NHD is also available through the state's Geographic Data Resource Site (GDRS).
|Section 2||Data Quality|
|Attribute Accuracy||The entry and identifier for the names match those in the Geographic Names Information System. The association of each name to reaches has been interactively checked. However, operator error could in some cases apply a name to the wrong reach.|
|Logical Consistency||Points, nodes, lines, and areas conform to topological rules. Lines intersect only at nodes, and all nodes anchor the ends of lines. Lines do not overshoot or undershoot other lines where they are supposed to meet. There are no duplicate lines. Lines bound areas and lines identify the areas to the left and right of those lines. Gaps and overlaps among areas do not exist. All areas close.|
|Completeness||Entire state is available. Border watersheds include linework from adjacent states and Canada. Detailed capture conditions are provided for every feature type in the Standards for National Hydrography Dataset - High Resolution available online at http://nationalmap.gov/standards/pdf/NHDH0799.PDF.|
In some areas USGS or state partners have revised linework based on newer aerial imagery. Feature-based metadata in the dataset tracks edit cycles.
|Horizontal Positional Accuracy||(At map scale)> Features with like dimensionality (for example, features that all are delineated with lines), or with or without like characteristics, that are within the tolerance are aligned by moving the features equally to a common point. Features outside the tolerance are not moved. Instead, a feature of type=connector is added to join the features. For any given area, feature-level metadata exists describing the original data capture sources and techniques and sources and any subsequent edits.|
|Vertical Positional Accuracy||Statements of vertical positional accuracy for elevation of water surfaces are based on accuracy satements made for U.S. Geological Survey topographic Quadrangle maps. These maps were compiled to meet National Map Accuracy Standards. For vertical accuracy this stndard is met if at least 90 percent of well-defined points tested are within on-half contour interval of the correct value. Elevations of water surface printon on the published maps meet this standard. The contour intervals of themaps vary. These elevations were trasncribed into the digital data. The accuracy of this transcription was checked by visual comparison between the data and the map.|
|Lineage||High-res NHD Creation processing and update processing is generally done a subbasin (HUC-8) unit at a time. An exception to this is the creation or updating of stream gage and dam events, which is generally done at a subregion (HUC-4) level. Feature-level metadata is stored in the database. Creation and edit cycles are documented with a new record- describing the responsible organization, edit date, processing steps, and source data used - in the NHDMetadata table. All features that are affected by that particular edit cycle are linked to the appropriate record in the NHDMetadata table via the NHDFeatureToMetadata table.
Creation of high-resolution NHD: High-res NHD was created by conflating the Medium-res (100k) NHD with a source set of 1:24,000-scale linework. NHD medium-resolution attributes (Reach Code, Feature Type, GNIS Name, GNIS ID) were attached to the 24K linework using an automated process, and a semi-automated process with manual review was used to verify that information was transferred correctly. Manual editing was used to add features, delete features, rename features, change geometry, or add attribution, as necessary. Only names and IDs existing within the Geographic Names Information System (GNIS) are eligible to be applied to the NHD. To support this process, USGS provided a set of ArcGIS-based conflation and review tools (NHDCreate), Tool User documentation and NHD Model Specifications, and training through its NHD Stewardship program. Topology rules within the NHD model were enforced by the tools.
Over most of the U.S., the 1:24,000-scale base line work for the high-resolution NHD is the 1:24,000 DLG bluelines from the USGS 24k topographic maps, either digitized directly from paper maps or DRG, or DLG lines scanned from the topos. In Minnesota, most HUC-8s were conflated to a different set of base 1:24,000 linework. A working group consisting of staff from USGS, EPA, LMIC, MPCA, and DNR were involved in determining the input data sources and processing decision rules for creating high-resolution NHD for Minnesota.
- NHD Flowlines (1-d) were conflated to the Minnesota DNR 24K streams layer. This layer originated as the streams layers digitized from 1;24,000 USGS topo maps by Mn/DOT for its Basemap program, with many enhancements to the data made by DNR, including creating 1-d flowpaths, creating connectivity through lake polygons , spatial referencing with the NWI polygons, and various other corrections. The DNR 24k streams layer used was named "strm_baseln3". The layer is now the "Stream Routes with Stream Types" feature class in the MNDNR Hydrography Dataset: https://gisdata.mn.gov/dataset/water-dnr-hydrography
- NHD Areas (2-d streams) and NHD Waterbodies (lakes/ponds) were conflated to the DNR 24k lakes layer. The DNR 24k lakes layer contains lake features derived from National Wetlands Inventory Open Water and fringe wetlands classifications, and the 2-dimensional (polygon) stream features derived from the NWI riverine classification. Unlike the standard DLG source material, the DNR 24k lakes layer does not include all wetlands which appear on the 1:24,000 USGS topo maps. A decision was made(at the recommendation of the Minnesota Department of Natural Resources) NOT to include all wetlands (Swamp/Marsh Waterbody feature type in NHD) until improved wetland data (such as from an updated National Wetlands Inventory delineation) was available. The DNR 24k lakes layerused was named is described at "lake_openwpy3". The layer is now the "Lakes and Open Water" feature class in the MNDNR Hydrography Dataset: https://gisdata.mn.gov/dataset/water-dnr-hydrography
- No additional features for NHD Lines and NHD Points were brought into the high-res NHD - the medium-resolution data set was used as input for NHD Lines and NHD Points.
The above source data was used by Minnesota state agencies creating high-res NHD, by USGS staff, and by some USGS contractors. It was generally used where HUC-8s were entirely within Minnesota. For border HUCs contractors generally went back to the 1:24,000 DLG linework as a source, so that one data source could be used for the entire HUC-8. For HUC-8s Minnesota shares with Wisconsin, Wisconsin DNR 24k line work was sometimes used as the input. Feature-level metadata within the NHD describes the originator and source data used for each HUC-8 for the original data creation.
NHD Point Events in the system so far represent USGS Stream Gages and dams reported to the National Inventory of Dams. These events were input and are maintained by USGS.
Organizations involved in high-resolution NHD creation for Minnesota included the Minnesota Land Management Information Center (now MnGeo), the Minnesota Pollution Control Agency, the Spatial Analysis Research Center at St. Cloud State University, USGS Water Resources Division Minnesota, and the USGS National Mapping Division. Funding was provided by USGS, EPA, USFS, and MPCA. Minnesota DNR provided source line work.
NHD Updates are performed, as needed, generally on a HUC-8 basis, using tools and process requirements provided by USGS, and supported through the USGS NHD Stewardship Program. Tools are desktop tools (NHDGeoEdit for ArcGIS 9.0 and earlier, NHDUpdate for ArcGIS 9.3 and later versions.) For editing, HUC-8s are checked out of the USGS national NHD database, then after updating and passing the QA/QC requirements, the updated HUC-8 is submitted back to USGS.
USGS has supported NHD with nationwide updates, as needed. Some of these have included: Maintenance Lite I and II, updating GNIS names, topo revision of large features (e.g., to match 2010 imagery), applying database model changes, and the like.
Recognized state stewards and sub-stewards can perform updates, as needed, to improve the network, correct flow direction, correct name placement, add new features from local sources, correct features, update features with new imagery (e.g., record stream course changes or channelizations). MnGeo has performed most of the state organization updates to date. Metropolitan Council added storm water features to the NHD in parts of the Metro.
Note that the DNR 24K streams and DNR 24K lakes layers used to create the MInnesota high-res NHD are no longer the "best available" data at DNR. Future updates will use features from the newer DNR Hydrography Geodatabase and other sources.
All of these updates are tracked in the NHDMetadata (update process) and NHDFeaturetoMetadata (which features were updated). Metadata must describe who did the updates, what types of updates they were doing, dates of the update process, and source materials used (e.g., what local data set, if revision based on imagery, what imagery was used.)
Lineage for the Watershed Boundary Dataset is covered in a separate metadata record. It should be noted that the current WBD was derived from the published "DNR Level 08 Catchments" layer, although due to edits at the national level there are a few discrepancies.
National: Any data downloaded from the USGS NHD site is in Geographic Coordinates, NAD83. A number of map extents and data formats are available, as outlined under "Ordering Instructions".
State: NHD in Minnesota's Geographic Data Resource Site (GDRS): The version of the NHD which is posted to the state's GDRS Site is a statewide extract downloaded from the USGS ftp site, in file geodatabase format. New state extracts are posted by USGS approximately quarterly, and MnGeo copies those extracts to the state's Geographic Data Resource Site. MnGeo upgradess the file geodatabase from ArcGIS 9.3.1 to ArcGIS 10.2.2 format, compresses the geodatabase (lossless option), and renames for consistency with GDRS naming conventions. ArcGIS .lyr files are are created.
|Section 3||Spatial Data Organization (not used in this metadata)|
|Section 4||Coordinate System|
|Horizontal Coordinate Scheme||Geographic|
|Horizontal Units||Decimal Degrees|
|Overview||The National Hydrography Dataset contains two feature datasets (Hydrography and WBD), with associated tables and relationships.
Feature Dataset Hydrography contains:
NHDAreaEventFC (currently empty)
NHDLineEventFC (currently empty)
Feature Dataset WBD contains:
WBDHU14 and WBDHU16 are currently empty.
|Detailed Citation||NHD Feature Catalog: http://nhd.usgs.gov/userguide.html?url=NHD_User_Guide/Feature_Catalog/NHD_Feature_Catalog.htm
NHD Model: http://nhd.usgs.gov/NHDv2.2_poster_062614.pdf
WBD Model: http://nhd.usgs.gov/WBDposter_6_30_09a.pdf
|Contact Person Information||Jeffrey D. Simley,
U.S. Geological Survey
Box 25046, MS 510 Denver Federal Center
Denver, CO 80225-0046
Phone: (303) 202-4131
Fax: (303) 202-4504
|Distributor's Data Set Identifier||NHD High Resolution - MN (water_national_hydrography_data)|
|Distribution Liability||From USGS: "We make every effort to provide and maintain accurate, complete, usable, and timely information on our Web sites. However, some USGS data and information accessed through these pages may, of necessity, be preliminary in nature and presented prior to final review and approval by the Director of the USGS. These data and information are provided with the understanding that they are not guaranteed to be correct or complete. Users are cautioned to consider carefully the provisional nature of these data and information before using them for decisions that concern personal or public safety or the conduct of business that involves substantial monetary or operational consequences. Conclusions drawn from, or actions undertaken on the basis of, such data and information are the sole responsibility of the user."|
|Ordering Instructions||Download of individual subbasins (HUC-8's) or groups of subbasins is available through the USGS National Map application/NHD Viewer http://viewer.nationalmap.gov/viewer/.
Prestaged subregions (HUC-4's - e.g., St. Croix River Basin, Minnesota River Basin) can be downloaded from ftp://nhdftp.usgs.gov/DataSets/Staged/SubRegions/.
A full state extract in file geodatabase format can be downloaded from ftp://nhdftp.usgs.gov/DataSets/Staged/States/
NWIS Stream gages and NID dams as NHD events can be downloaded from: ftp://nhdftp.usgs.gov/DataSets/National//
The Minnesota Geospatial Commons distributes the latest version of the USGS state extract in file geodatabase and shapefile formats.Because the state extract includes full HUC-8 delineations this file overlaps into adjacent states and provinces. The Online Linkage below points to this version of the dataset.
|Online Linkage||I AGREE to the notice in "Distribution Liability" above. Clicking to agree will either begin the download process, link to a service, or provide more instructions. See "Ordering Instructions" above for details.|
|Section 7||Metadata Reference|
|Contact Person Information||Nancy Rader,
Minnesta Geospatial Information Office (MnGeo)
658 Cedar Street
St. Paul, MN 55155
|Metadata Standard Name||Minnesota Geographic Metadata Guidelines|
|Metadata Standard Version||1.2|
|Metadata Standard Online Linkage||http://www.mngeo.state.mn.us/committee/standards/mgmg/metadata.htm|