Search Help
GIS Coverage of the National Water-Quality Assessment Study-Unit Investigations in the conterminous United States (NAWQA)

[ Get Data ]
[ Update this Record ]

Abstract: This is a coverage of the boundaries and codes used for the U.S. Geological
Survey National Water-Quality Assessment (NAWQA) Program Study-Unit
investigations for the conterminous United States, excluding the High Plains
Regional Ground-Water Study.

The National Water-Quality Assessment Program is designed to describe the
status and trends in the quality of the Nation's ground- and surface-water
... View entire text
Related URL
Description: GIS Coverage in Arc/INFO Export file and Shapefile format.

Description: Homepage of the USGS National Water Quality Assessment Program (NAWQA).
Multimedia Sample
Small multimedia sample image
View full image

Caption:  NAWQA Program Study-Unit Boundaries
Geographic Coverage
Spatial coordinates   
  N: 48.25   S: 22.87   E: -65.35   W: -127.88

Data Set Citation
Dataset Originator/Creator: Hitt, K.J. and Nakagki, N.
Dataset Title: National Water-Quality Assessment (NAWQA) Study-Unit Investigations in the conterminous United States
Dataset Release Date: 1999-07-01
Dataset Release Place: Reston, Virginia
Dataset Publisher: USGS
Data Presentation Form: Map
Location Keywords
View entire list
Quality This data set is used primarily to display the location of NAWQA Study Units
and for analysis of data at the national scale. It is not recommended for
either local or regional analysis due to the small scale of most of the
features. Accuracy is good at 1:2,000,000 or smaller in most cases. The
... View entire text
Access Constraints None
Use Constraints Accuracy is good at 1: 2,000,000 or smaller in most cases. The Study-Unit
source maps come from various sources and scales.
Data Set Progress
Originating Center
Data Center
Clean Air Markets Division, U.S. Environmental Protection Agency Supplemental Info
Data Center URL:

Data Center Personnel
Phone: 202-564-9180
Email: camdgis at
Contact Address:
Clean Air Markets Division
1200 Pennsylvania Avenue, NW
Mail Code 6204J
City: Washington
Province or State: DC
Postal Code: 20460
Country: USA
View entire list
Distribution Media: ftp
Distribution Size: 6184720 bytes
Distribution Format: ArcInfo export format
Fees: No fees

Distribution Media: ftp
Distribution Size: 16303646 bytes
Distribution Format: ArcView shapefile
Fees: No fees
Phone: (301) 614-6898
Fax: 301-614-5268
Email: Tyler.B.Stevens at
Contact Address:
NASA Goddard Space Flight Center
Global Change Master Directory
City: Greenbelt
Province or State: MD
Postal Code: 20771
Country: USA
Allord, G.J., 1992, 1:2,000,000 Hydrologic Unit map of the
conterminous United States, Version 1.1.2. Available through the
internet at ""
View entire list
Extended Metadata Properties
(Click to view more)

Creation and Review Dates
DIF Creation Date: 2002-11-14
Last DIF Revision Date: 2016-11-18
[ Update this Record ]