Course of the Colorado River Davis Dam in Pyramid Canyon above Laughlin, Nevada, where a bridge carries NV 163 (Laughlin Highway)/AZ 95 over the Colorado River. Prior to the completion of the Hoover Dam Bypass project in 2010, this bridge was the main crossing for freight traffic between Arizona and Nevada as trucks were not allowed over Hoover Dam for security reasons after the September 11, 2001 attacks. The Colorado then passes by Bullhead City, Arizona and Fort Mohave, Arizona and the Fort Mojave Reservation. The Colorado forms the border of California to the west and Arizona to the east for most of its course
Course of the Colorado River through the desert Lower Colorado River Valley (LCRV), where its character changes significantly from fast-flowing whitewater to a low gradient braided stream with a wide floodplain. Here, the Colorado River ranges in width from and from in depth. It becomes a losing stream, with a gradual reduction in volume both due to evaporation in the hot desert climate and massive diversions for irrigation, urban areas, industry and thermo-electric power generation. The average flow rate of at Davis Dam diminishes to just at the Mexican border. At Needles, California the Colorado is crossed by Interstate 40; shortly downstream it passes the