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
Floods in the United States: 1901–2000 which was recorded at on July 1. The Colorado, which is usually dry at the mouth due to extensive diversions, reached the Gulf of California for the first time since the 1960s. Due to a spillway design error at Glen Canyon coupled with the relentless flooding, the dam at Glen Canyon very nearly failed, which would have emptied Lake Powell (the second-largest man-made lake in the US) and flooded out the entire lower valley of the Colorado River, cutting off water supplies to millions of people. By August as the water finally began to recede, the dam held, though only