This is a GENERALIZED version of the boundaries and codes used for the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program Study-Unit investigations in the conterminous United States, excluding the High Plains Regional Ground-Water Study. The data set represents the areas to be studied during the second decade of the NAWQA Program, from 2001-2012 ("cycle 2"). The coverage is intended only for drawing ILLUSTRATIONS, NOT for spatial analysis.
Citation Information
| Publication Year | 2006 |
|---|---|
| Title | Generalized boundaries of the National Water-Quality Assessment (NAWQA) Study-Unit Investigations in the conterminous United States 2001-2012 |
| DOI | 10.3133/70046921 |
| Authors | K.J. Hitt |
| Publication Type | Report |
| Publication Subtype | USGS Unnumbered Series |
| Index ID | 70046921 |
| Record Source | USGS Publications Warehouse |