U.S. Route 93 in Nevada portion of abandoned railroad right-of-way. A shopping center now sits where the original truck bypass alignment once ran. US 93 was realigned again on October 19, 2010, when the Mike O'Callaghan – Pat Tillman Memorial Bridge over the Black Canyon of the Colorado River opened to vehicular traffic. With that, the highway no longer passes over Hoover Dam, and the state-maintained portion of the replaced route was renamed as Hoover Dam Access Road (SR 172). In 2011, US 93 from Buchanan Boulevard to the Nevada terminus of the Hoover Dam Bypass was expanded to four through lanes with dedicated turn
Course of the Colorado River into the Salton Sink flooding farmland and creating the Salton Sea, which still exists today as the largest inland body of water in California. The river was finally diverted back to its present course in 1907. Geological evidence suggests that this has happened naturally many times in the past, filling Lake Cahuilla, with the floodwaters slowly evaporating over spans of decades before being re-flooded by the Colorado. The Colorado River meets the Mexico–United States border at the Northern International Boundary (NIB), where the Morelos Dam diverts nearly the entire remaining flow into the Reforma Canal and the Tijuana Aqueduct. Most