Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Existing maps and Google Earth. Existing maps were hand-made and could not provide a level of details sufficient for the required purpose. Google Earth satellite images came handy by providing maps of portions of the River of sufficient resolution to be used for planning purposes.
