A consortium with a track record of big public infrastructure initiatives in Colorado will spearhead the $1.2 billion project to expand Interstate 70 through northeast Denver and Aurora amid persisting controversy and federal court challenges.

Kiewit Meridiam Partners rose to the top of the list of four groups that were vying for the public-private partnership, said Colorado Department of Transportation executive director Shailen Bhatt.

Officials were drawn to KMP, in part, because of its hope to shave about six months off the planned five-year timeline for construction, which is expected to cause headaches for motorists.

“Today, we take a big step forward in replacing what you see behind us,” Bhatt said at a Thursday news conference announcing the decision as I-70’s crumbling viaduct provided the backdrop. “We are moving full speed ahead.”

KMP will design, build and finance the project — known as Central 70 — and operate and maintain it for 30 years. Financial terms have not been finalized.

The conglomerate’s experience in Colorado includes leading metro Denver’s Transportation Expansion Project, or T-REX, that a decade ago expanded Interstate 25 south of the city, as well as construction of the Eisenhower Tunnel and the stretch of I-70 through Glenwood Canyon.

Construction for Central 70 — which CDOT calls the largest infrastructure initiative in Colorado’s history — is slated to begin at the start of next year. It calls for the widening of the six-lane interstate between Brighton Boulevard and Chambers Road, with a new managed express toll lane in each direction.

The project is also slated to replace the 1.8-mile viaduct with a below-grade highway between Brighton and Colorado boulevards, through the Elyria-Swansea neighborhood. Part of that section will be topped by a 4-acre parkland next to Swansea Elementary that officials hope will connect communities that were divided when I-70 was built.

During construction, I-70 will remain open — a CDOT requirement for groups hoping to win the bid — and can only be fully shut down five times total, and only on weekends and/or at night. Each day, about 200,000 vehicles — many of them tractor-trailers — travel the 10-mile stretch targeted for construction — a number expected to balloon as Colorado’s population quickly rises.

“We’re not making this easy on the contractor,” said Rebecca White, CDOT’s deputy director of the initiative. “They have to keep this interstate moving during the project.”

Joe Wingerter, vice president of Kiewit Infrastructure Group, vowed to limit community impact from the project with the help of $1 million in local investments.

“I think they made a good selection and we are going to make them proud,” he said. “We are going to deliver this project within the time frame — on time and on budget.”

The project, however, is facing legal challenges from environmental and community groups that contend it will split heavily Latino neighborhoods along the project’s path and create serious health risks. Groups that include local activists and the Sierra Club have sued the Federal Highway Administration — which in January granted federal approval for the I-70 project — in an effort to halt construction.

Brad Evans, a community activist working to stop the project and creator of the “Ditch the Ditch” campaign, said he is not deterred by CDOT’s choice of a contractor. Legal challenges are moving forward, he said, even as officials gear up to begin construction.

“It’s not a done deal by any means just because the highway department is moving forward,” Evans said.

CDOT, however, says it is pressing forward until it hears otherwise from the courts.

White says 56 residential properties will need to be acquired for the project — two-thirds of which have already been purchased by the agency.

“It’s telling us in every possible way that it’s time for it to go,” she said of the I-70 infrastructure to be replaced, which is five decades old and quickly falling apart.

KMP beat out three competitors: Front Range Mobility Group, 5280 Connectors and I-70 Mile High Partners.

CDOT says contract negotiations with KMP are slated to begin almost immediately and wrap up sometime this winter.