This coverage was used to display seasonal maps of precipitation and temperature for the conterminous United States. This data set was used to display drainage basins for the conterminous United States. This coverage is intended as a thematic data layer representing average annual runoff, in inches per year, for the conterminous United States. Appropriate maps of the data can show the geographical distribution of runoff in tributary streams for the years 1951-80 and can describe the magnitudes and variations of runoff nationwide. The data was prepared to reflect the runoff of tributary streams rather than in major rivers in order to represent more accurately the local or small scale variation in runoff with precipitation and other geographical characteristics.
Point features present.
Spatial point coverages for the entire U.S. and U.S. territories from these databases are created from CSV formatted files imported into ArcView. The coverages were then reprojected from Albers Conic Equal Area projection NAD83 to geographic decimal degrees NAD83. Additionally WDM stations which bordered an EPA region or contained within 8-digit hydrologic units that crossed region boundaries were also included. The WDM.DBF polygon attribute table contains all the attributes and values needed to display graphically location of the WDM stations. The items in WDM.DBF are listed, defined, and described in the section above.