USGS Streamgages Linked to the Medium Resolution NHD
Dataset Identification:
Resource Abstract:
The locations of approximately 23,000 current and historical U.S. Geological Survey (USGS) streamgages in the United States
and Puerto Rico (with the exception of Alaska) have been snapped to the medium resolution National Hydrography Dataset (NHD).
The NHD contains geospatial information about mapped surface-water features, such as streams, lakes, and reservoirs, etc.,
creating a hydrologic network that can be used to determine what is upstream or downstream from a point of interest on the
NHD network. An automated snapping process made the initial determination of the NHD location of each streamgage. These initial
NHD locations were comprehensively reviewed by local USGS personnel to ensure that streamgages were snapped to the correct
NHD reaches. About 75 percent of the streamgages snapped to the appropriate NHD reach location initially and 25 percent required
adjustment and relocation. This process resulted in approximately 23,000 gages being successfully snapped to the NHD. This
dataset contains the latitude and longitude coordinates of the point on the NHD to which the streamgage is snapped and the
location of the gage house for each streamgage. A process known as indexing may be used to create reference points (event
tables) to the NHD reaches, expressed as a reach code and measure (distance along the reach). Indexing is dependent on the
version of NHD to which the indexing is referenced. These data are well suited for use in indexing because nearly all the
streamgage NHD locations have been reviewed and adjusted if necessary, to ensure they will index to the appropriate NHD reach.
Flow characteristics were computed from the daily streamflow data recorded at each streamgage for the period of record. The
flow characteristics associated with each streamgage include: First date (year, month, day) of streamflow data Last date (year,
month, day) of streamflow data Number of days of streamflow data Number of days of non-zero streamflow data Minimum and maximum
daily flow for the period of record (cubic feet per second) Percentiles (1, 5, 10, 20, 25, 50, 75, 80, 90, 95, 99) of daily
flow for the period of record (cubic feet per second) Average and standard deviation of daily flow for the period of record
(cubic feet per second) Mean annual base-flow index (BFI) computed for the period of record (fraction, ranging from 0 to 1)
Year-to-year standard deviation of the annual base-flow index computed for the period of record (fraction) Number of years
of data used to compute the base-flow index (years) The streamflow data used to compute flow characteristics were copied from
the NWIS-Web historical daily discharge archive (http://waterdata.usgs.gov/nwis/sw) on June 15, 2005.
Citation
Title USGS Streamgages Linked to the Medium Resolution NHD
publication Date
9999-01-01
presentationForm
mapDigital
Series
Name Data Series
Issue DS-195
cited responsible party
-
publisher
organisation Name
U.S. Geological Survey
Contact information
Address
, Reston, Va
cited responsible party
-
originator
organisation Name
David W. Stewart, Alan Rea and David M. Wolock
USGS Streamgage Network Locations for NHD Version June 2002 Medium Resolution
Streamflow statistics
Streamflow data
Base flow index
Hydrography
National Hydrography Dataset
NHD
Streamgages
inlandWaters
thesaurus name >
Title Gages
Location keywords:
United States of America
United States
USA
Alabama
Arizona
Arkansas
California
Colorado
Connecticut
Deleware
District of Columbia
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
North Dakota
Ohio
Oklahoma
Oregon
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Utah
Vermont
Virginia
Washington
West Virginia
Wisconsin
Wyoming
Puerto Rico
thesaurus name >
Title
purpose:
The purpose of this dataset is to document the location of USGS active and historical streamgages on the NHD version 2002
medium resolution (1:100,000-scale). This dataset can also be used to index these USGS streamgages to other versions of the
NHD as well. The flow characteristics tied to each of the streamgages attached to the NHD will greatly facilitate hydrologic
analysis and can be used for such things as the development of regional statistical models of streamflow at ungaged locations.
Resource language:
eng; USA
Resource progress code:
completed
Resource Maintenance Information
maintenance or update frequency:
asNeeded
Constraints on resource usage:
Constraints
Use limitation statement:
Although this data set has been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed
or implied is made by the U.S. Geological Survey as to the accuracy of the data and related materials. The act of distribution
shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this
data, software, or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not
imply endorsement by the U.S. Government.
Constraints on resource usage:
Legal Constraints
use constraint:
otherRestrictions
Other constraints
Use Constraints: None
Constraints on resource usage:
Legal Constraints
Access Constraints
otherRestrictions
Other constraints
Access Constraints: None
Constraints on resource usage:
Security Constraints
Classification
unclassified
Classification
System None
Handling
Description None
Spatial representation type code:
vector
Processing environment:
Native Dataset Environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.1.0.722
Resource extent
Geographic Extent
Geographic Bounding Box
westBoundLongitude
-159.750305
eastBoundLongitude
-65.302468
northBoundLatitude
48.999946
southBoundLatitude
17.956547
Temporal Extent
2005-01-01
Credits:
David W. Stewart, Alan Rea and David M. Wolock
point of contact
-
pointOfContact
organisation Name
US Gelogical Survey
Contact information
Telephone
Voice
Address
437 USGS National Center, Reston, Va., 22092
Country USA
source description
Source Contribution: Point locations and hydrologic dataSource Type Digital Data
source citation
Title NWIS-Web streamflow data
publication Date
9999-01-01
cited responsible party
-
originator
organisation Name
U.S. Geological Survey
Resource extent
Temporal Extent
2005-06-15
AbsoluteExternalPositionalAccuracy
name Of Measure Horizontal Positional Accuracy Report
evaluation Method Description
The positional accuracy of the NHD locations is very good. Most locations were reviewed by USGS Water Science Center personnel
who knew the precise locations for the vast majority of all the streamgages. These reviewed locations have the REVIEWED field
set to 'Y', which stands for "yes, these locations have been reviewed." In general, the positional accuracy of the active
streamgage location and streamgages that were active in the past 30 years could be considered slightly more accurate then
the older historical streamgages. Most NHD locations were reviewed by USGS Water Science Center personnel. The NHD locations
of 17,482 are within a few meters of the delineated stream reach, since they were automatically snapped to the nearest latitude/longitude
vertices in the NHD arc. The remaining 4,271 NHD locations were manually adjusted during the review and moved to the correct
locations. Although the new locations were not snapped exactly to NHD vertices, reviewers were instructed to place the point
so that it would be close enough to snap to the proper position on the NHD. The NHD locations not reviewed by USGS Water Science
Center personnel are also included. These locations have the REVIEWED field set to 'N' which stands for "not reviewed. These
locations were snapped to the NHD in an automated process, but no review has been done to ensure they snapped to the proper
NHD reach. A total of 2,042 gages in the dataset were not reviewed."
notes: This metadata was automatically generated from the FGDC Content Standards for Digital Geospatial Metadata standard (version
FGDC-STD-001-1998) using the 2012-06-20T17:21:00 version of the FGDC RSE to ISO 19115-2 transform.