Dataset Identification:
Resource Abstract:
- description: This data set represents the average contact time, in units of days, compiled for every catchment of NHDPlus
for the conterminous United States. Contact time, as described in Wolock and others (1989), is the baseflow residence time
in the subsurface. The source data set was the U.S. Geological Survey's (USGS) 1-kilometer grid for the conterminous
United States (D.M. Wolock, U.S. Geological Survey, written commun., 2008). The grid was created using a method described
by Wolock and others (1997a; see equation 3). In the source data set, the contact time was estimated from 1-kilometer resolution
elevation data (Verdin and Greenlee, 1996 ) and STATSGO soil characteristics (Wolock, 1997b). The NHDPlus Version 1.1 is an
integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography
Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale
NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage
areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the
New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building
"walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM)
is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team
from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that
this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized
by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic
Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River
basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains
NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins,
contains NHDPlus Production Units 4, 5, 7 and 9. MRB4, covering the Missouri River basins, contains NHDPlus Production Units
10-lower and 10-upper. MRB5, covering the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf River basins, contains NHDPlus
Production Units 8, 11 and 12. MRB6, covering the Rio Grande, Colorado and Great Basin River basins, contains NHDPlus Production
Units 13, 14, 15 and 16. MRB7, covering the Pacific Northwest River basins, contains NHDPlus Production Unit 17. MRB8, covering
California River basins, contains NHDPlus Production Unit 18.; abstract: This data set represents the average contact time,
in units of days, compiled for every catchment of NHDPlus for the conterminous United States. Contact time, as described in
Wolock and others (1989), is the baseflow residence time in the subsurface. The source data set was the U.S. Geological Survey's
(USGS) 1-kilometer grid for the conterminous United States (D.M. Wolock, U.S. Geological Survey, written commun., 2008). The
grid was created using a method described by Wolock and others (1997a; see equation 3). In the source data set, the contact
time was estimated from 1-kilometer resolution elevation data (Verdin and Greenlee, 1996 ) and STATSGO soil characteristics
(Wolock, 1997b). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates
many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus
includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs).
NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first
widely used in New England, and thus referred to as "the New England Method." This technique involves "burning
in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset
(WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with
the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental
Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated
process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States.
The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others,
2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering
the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes,
Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus Production Units 4, 5, 7 and 9. MRB4, covering
the Missouri River basins, contains NHDPlus Production Units 10-lower and 10-upper. MRB5, covering the Lower Mississippi,
Arkansas-White-Red, and Texas-Gulf River basins, contains NHDPlus Production Units 8, 11 and 12. MRB6, covering the Rio Grande,
Colorado and Great Basin River basins, contains NHDPlus Production Units 13, 14, 15 and 16. MRB7, covering the Pacific Northwest
River basins, contains NHDPlus Production Unit 17. MRB8, covering California River basins, contains NHDPlus Production Unit
18.
Citation
- Title Attributes for NHDPlus Catchments (Version 1.1)for the Conterminous United States: Contact Time, 2002.
-
- creation Date
2018-05-20T02:59:58.797054
Resource language:
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Metadata data stamp:
2018-08-06T23:15:08Z
Resource Maintenance Information
- maintenance or update frequency:
- notes: This metadata record was generated by an xslt transformation from a dc metadata record; Transform by Stephen M. Richard, based
on a transform by Damian Ulbricht. Run on 2018-08-06T23:15:08Z
Metadata contact
-
pointOfContact
- organisation Name
CINERGI Metadata catalog
-
- Contact information
-
-
- Address
-
- electronic Mail Address cinergi@sdsc.edu
Metadata language
eng
Metadata character set encoding:
utf8
Metadata standard for this record:
ISO 19139 Geographic Information - Metadata - Implementation Specification
standard version:
2007
Metadata record identifier:
urn:dciso:metadataabout:2b603f05-5e7b-4002-bf24-e59575d072a0
Metadata record format is ISO19139 XML (MD_Metadata)