The US Department of Transportation (USDOT) has opened the new $71.3m North I-25 Express Lanes project in Denver, Colorado.

The scope of the project included a six-mile expansion of the High Occupancy Toll (HOT) Lanes, which will offer additional travel options to motorists, as well as ease traffic flow in the area.

Of the $71.3m of the project value, $52.5m came from federal funds, including a $15m Transportation Investment Generating Economic Recovery (TIGER) grant.

"These new express lanes will help improve the quality of life for those living and working in the Denver area by giving them new options for beating rush-hour traffic."

The amount was used to increase the capacity of I-25 with additional tolled express lanes in each direction between US 36 and 120th Avenue to reduce long-term operating and maintenance costs.

The US Transportation Secretary Anthony Foxx said: "These new express lanes will help improve the quality of life for those living and working in the Denver area by giving them new options for beating rush-hour traffic.

"This innovative approach will also help commuters get to work safely and on time and support economic growth for the entire region."

The new lanes linked to the existing I-25 Express Lanes lead into and out of downtown Denver.

These lanes provide motorists with the option of carpooling or paying toll to commute on the HOT lanes in order to enjoy a faster and better journey, or use the existing non-tolled lanes.

Federal Highway Administrator Gregory Nadeau said: "Denver drivers have needed these extra options for quite some time.

"Best of all, we’re keeping drivers safe and improving a key element to the Denver area’s freight economy."

The new lanes will also help reduce fuel consumption by up to 10 million gallons, as well as greenhouse gas emissions by about 90,000 metric tonnes because of less congestion and reduced vehicle delay.