In the short span of four months, the buildings that will come to house roughly 800 new students have begun to rise from the mounds of dirt and barren concrete foundations that had previously dominated the Prospect Street site.

After years of planning, delayed starts and hundreds of millions of dollars in fundraising, Yale’s most ambitious capital project in over 50 years is now 10 months underway. Since the project ceremonially broke ground in April, construction has appeared to move quickly, with the shells of the two new colleges now in plain sight along Prospect Street. Despite this progress, what lies behind the fenced-in perimeter of the half-dozen-acre property is far less conclusive.

Of the eight on-site construction workers interviewed — ranging from welders to concrete pourers to excavation workers — views on the progress of the construction ranged from cautiously optimistic to outright discouraged.

“The whole project is delayed, mostly in the carpentry and the rebar,” said one worker who asked to remain anonymous given contractual stipulations prohibiting workers from speaking to the press. “I mean we are making headway, but still it may not be done by the date it is supposed to be finished.”

But according to University Spokesman Tom Conroy, at this point the project is approximately 20 percent complete and the two buildings remain on schedule for their fall 2017 opening. Still, he noted, the project has not been without its difficulties.

The project — which is estimated to cost the University over half a billion dollars — was designed by Robert A.M. Stern Architects. According to the April 2011 architect renderings, the most recently available designs, the colleges will include features such as three towers, eight courtyards and dormitories to accommodate some 800 new students. The colleges are Yale’s first expansion since women were admitted in 1969.

“One of the largest challenges has been the coordination of logistics on the site,” Conroy wrote in an email. “Orchestrating the flow of people, materials and equipment, in a safe, orderly manner, given the size of the project and the density of buildings on the site has been a constant challenge for the construction manager.”

Conroy said that by the end of the calendar year, the superstructures of the colleges — in short, the frameworks of the buildings — will be completed once the steel beams forming the gabled roofs are put in place. He added that as work on the superstructure continues, mechanical and electrical workers are working on the basement levels of the buildings and will later begin work on the completed floors.

According to one construction worker from the Massachusetts-based firm J. L. Marshall & Sons, a subcontractor tasked to oversee construction of the south college building, the bulk of the work is currently at the “structural stage,” in which the concrete shells of the buildings are reinforced with rebar. Other work currently underway includes excavation, iron welding and electrical and mechanical work.

Still, there was a lack of consensus among the workers interviewed on whether construction was following schedule.

“The pace is going well, we are a little bit behind but we are catching up quick,” said one worker, who also asked to remain anonymous. “The summer weather has been helpful. Winter was tough. But they never stopped for even a day. All other sites were shut down, and we didn’t stop for a day.”

Another worker, who is tasked with pouring concrete, said the 2017 deadline is ambitious given the scale of the project. He added that as a result, there is a sense that the work is always behind, even though he and other workers have been putting in 65–70 hour weeks. Others, however, voiced optimism about the pace of the construction.

“We are mostly on schedule; there are setbacks here and there, but that is true of any job,” said one ironworker.