Rail transit officials showed off the future operations and control center Thursday to mark the first anniversary of the resumption of construction on the $5.26 billion project.

Set between Leeward Community College and the Waipahu High School football stadium, the 43-acre site will serve as the operational brain of the rail system.

"This is the first driverless system in the United States," said Honolulu Authority for Rapid Transportation Executive Director Dan Grabauskas, underscoring the critical nature of the operations center. "All of the trains will be operated from one central location along the entire 20-mile location."

The site, expected to be done by January 2016, in time to house the first rail cars when they are delivered to Oahu that spring, will feature four main buildings: operations and servicing, track maintenance, train washing and wheel alignment.

Grabauskas called the progress on the 160,000-square-foot operations and control center "significant," adding that the site was nothing more than "grassy hillside" that sloped about 100 feet from one end of the property to the other. About 250,000 cubic yards of dirt was shuffled around to flatten the surface of the property, he said.

The operations and servicing building is the largest structure on the site. The makai end of the building will house the operators who control the trains. The mauka end will contain two bays where trains can be pulled in for maintenance, inspection and repair.

The track maintenance building, on the Leeward Community College side of the property, will house the equipment used for inspecting and maintaining the guideway on which the trains will run. That work is expected to be done from midnight until 4 a.m. daily, the four hours each day the trains are not operating.

The wheel alignment building will house the specialized equipment needed to maintain the steel wheels of the train vehicles "to make sure there’s a nice, clean fit" with the guideway. Yet to be constructed is a train exterior wash facility.

The rail line through the property will go in next spring after the buildings are constructed and final grading of the grounds is completed, Grabauskas said.

The project is part of a $200 million contract issued to the Kiewit/Kobayashi Joint Venture. Lance Wilhelm, Kiewit Hawaii senior vice president, said the contract includes not just construction of the rail operations and control center, but also the steel for the entire 20-mile track.

Wilhelm said among the most challenging aspects of the project was the placing of approximately 20,000 feet of underground utility lines.

Grabauskas said that completion of the rail operations and control center is expected to coincide with the end of construction for the first 10-mile segment of the rail line, taking it from East Kapolei to Aloha Stadium in spring 2016 so that the trains can be tested.

He reiterated that HART’s recent decision to rebid the contracts for the nine rail stations along that first segment, due to the unexpectedly high bids that were submitted, means the original 2017 start of operations for the first 10-mile segment will now likely be moved to 2018.

Grabauskas said the city still intends to have the entire 20-mile line, taking riders from East Kapolei to Ala Moana, by the end of 2019 as required by federal transit officials as a condition for $1.55 billion in funding.