The main map shows average annual streamflow in cubic feet per second. An attached supplementary map, at a scale of 1:40 000 000, displays the reliability of the river discharge data which the above mentioned map is based on.
List of 4th Edition Maps
List of Map Archive Collections
Download full size map ( 1,977 KB JPEG, 3030 x 2130 pixels )
Download Map in PDF ( 2,046 KB, Adobe Acrobat Reader required )