Denver International Airport is suing the city's Regional Transportation District to recover $53 million in costs for contracted work on the airport's Hotel and Transit Center Project, still under construction. Airport officials filed the lawsuit after a mediator refused to grant DIA the full amount from RTD. The money would be used to pay for site excavation, roadways, train-platform construction and other infrastructure work at the airport terminal. Both agencies say the other one should pay for the improvements.

DIA, which is owned by the city of Denver, is working under an intergovernmental agreement with RTD to build a transit center at the south end of the terminal. The project includes a train station for commuter rail that will connect the airport with downtown Denver. The rail line is more than 50% complete.

The centerpiece of the airport project is a 500-room, 14-story Westin hotel and conference center at the south end of the main terminal, near the train station.

The initial cost for the Airport Hotel and Transit Center Project—$500 million, when it broke ground in early 2012—has vaulted to $544 million, says Stu Williams, program manager in charge of the project for DIA. He declined to comment on the lawsuit, which is now working through the appeals process, but says, "This is not a new issue."

DIA began the dispute-resolution process when design evaluations revealed that, for some elements of the project, pricing was not sufficient. The two agencies sought, in May 2012, the help of a mediator, who decided RTD was responsible for $7.8 million and DIA was responsible for the rest. The airport was unhappy with the ruling and sued RTD for the balance.

Kevin Flynn, RTD FasTracks public information officer, says the dispute is "a matter of where the line is drawn between what we do and what they do." He says the rail line and airport train station will still finish as scheduled in January 2016.