In this June 8, 2016 photo, men work in the new underground subway tunnel below Ipanema neighborhood in Rio de Janeiro. (AP Photo/Felipe Dana)

The Olympic games start in seven weeks and the fourth line of Rio de Janeiro’s subway system is yet to be finished.

The fourth line is vital for the Olympics because it will run from Ipanema Beach to the Olympic Village in Barra da Tijuca, and to the majority of the competition venues, in less than 15 minutes. To compare, the drive time for that same commute runs over an hour at minimum.

“Every hour counts,” Rodrigo Vieira, Rio de Janeiro’s transportation head, told the Associated Press, insisting the job would be finished. “We are working around the clock, 24/7 with 1,000 workers in each station.”

But not everyone is as optimistic.

If the city somehow finishes the expansion on time, there will be four days in between the launch date and the Olympics opening date. Transportation experts are leery.

“They are leaving so little time to try this massive system,” said Jose Manoel Ferreira Goncalves, president of FerroFrente, an organization of railway experts. “What guarantee do we have that such a sensitive and complicated project is in order?”

“We want to know whether shortening the time to test the subway puts the safety of the passengers at risk,” said Jonas Lopes, president of Rio state’s court of auditors.

A backup plan including special lanes and a rapid transit bus system has been put in place, just in case the fourth line isn’t finished by the scheduled date.

The financial situation in Rio has plunged dramatically from the highs of 2007, as the acting governor declared a state of financial disaster on Friday. The state isn’t paying its teachers and retired workers or providing basic necessities to some government employees, like toilet paper at police stations. The state also neglected to pay the most recent installment of a loan to the French Development Agency. And that agency is helping pay for the subway expansion.

“Rio’s financial worries are notorious. I acknowledge that it’s not a small feat [for the federal government] to approve a loan to a state in financial problems,” the state’s financial secretary, Julio Bueno, told the AP. “On the other hand, we have the Olympics. The subway is vital.”