Attributes for NHDPlus Catchments (Version 1.1) in the Conterminous United States: Artificial Drainage (1992) and Irrigation Types (1997)

This tabular dataset represents the estimated area of artificial drainage for the year 1992 
and irrigation types for the year 1997 compiled for every catchment of NHDPlus for the 
conterminous United States. The source datasets were derived from tabular National 
Resource Inventory (NRI) datasets created by the National Resources Conservation 
Service (NRCS, U.S. Department of Agriculture, 1995, 1997).  Artificial drainage is 
defined as subsurface drains and ditches.  Irrigation types are defined as gravity and 
pressure.  Subsurface drains are described as conduits, such as corrugated plastic 
tubing, tile, or pipe, installed beneath the ground surface to collect and/or convey 
drainage. Surface drainage field ditches are described as graded ditches for collecting 
excess water.  Gravity irrigation source is described as irrigation delivered to the farm 
and/or field by canals or pipelines open to the atmosphere; and water is distributed by 
the force of gravity down the field by:
			 (1) A surface irrigation system (border, basin, furrow, corrugation, wild flooding, etc.) or
			 (2) Sub-surface irrigation pipelines or ditches. Pressure irrigation source is described 
as irrigation delivered to the farm and/or field in pump or elevation-induced pressure pipelines, 
and water is distributed across the field by:
			  (1) Sprinkle irrigation (center pivot, linear move, traveling gun, side roll, hand move, 
big gun, or fixed set sprinklers), or
			  (2) Micro irrigation (drip emitters, continuous tube bubblers, micro spray or micro sprinklers). 
NRI data do not include Federal lands and are thus excluded from this dataset.  The tabular data for 
drainage were spatially apportioned to the National Land Cover Dataset (NLCD, Kerie Hitt, 
written commun., 2005) and the tabular data for irrigation were spatially apportioned to an enhanced 
version of the National Land Cover Dataset (NLCDe, Nakagaki and others 2007)
		
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. Geological 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.

Tags: artificial-drainage, cali, california, catchment, cogb, conterminous-united-states, ditches, environment, geoscientificinformation, glmr, great-lakes-ohio-upper-mississippi-and-souris-red-rainy, inlandwaters, irrigation, lmtg, lower-mississippi-arkansas-white-red-and-texas-gulf, major-river-basin, missouri, mori, mrb, mrb1, mrb2, mrb3, mrb4, mrb5, mrb6, mrb7, mrb8, national-resource-inventory, nawqa, nema, new-england-and-mid-atlantic, nhdplus, pacific-northwest, panw, rio-grande-colorado-and-great-basin, sagt, south-atlantic-gulf-and-tennessee, sparrow, subsurface-drains-drainage, tile-drains, usgs-6f608721-c54a-4413-b1ae-04fc09527bf9
Organization: Department of the Interior