The Hoover Dam and Black Canyon are amazing parts of this country, but the traffic backups on U.S. 93, which travels over the dam, leave something to be desired.

Beyond the massive waste of time to drivers, idling cars and trucks send harmful emissions into the Earth’s atmosphere. And since the Sept. 11, 2001 terrorist attacks, the delays have worsened because of increased security. Making matters more inconvenient was a security-motivated ban on all tractor-trailer trucks traveling on the dam that required the gas-guzzlers to take a 75-mile detour.

But today, the delays, the detours and the unnecessary pollution are about to end. After five years of construction and decades of planning, the Hoover Dam Bypass Project has ended, and now one of the most impressive bridges in America spans the Colorado River.

On Thursday, the Department of Transportation dedicated the Mike O’Callaghan-Pat Tillman Memorial Bridge. The bridge is the longest single-span concrete bridge in the Western Hemisphere and one of the tallest in America. It is four lanes wide, instead of the two lanes that go over the dam, and it takes travelers 3.5 miles to cross the Hoover Dam rather than the 75-mile alternative.

It seems good for traffic, good for security and good for the planet. (And let’s not forget how cool this thing looks.) Now if we can just get some green cars and trucks to travel over the bridge, this will truly be an environmental and engineering success.