The construction of Yale’s two new residential colleges was postponed indefinitely because of the recession, but Provost Benjamin Polak announced Monday that the university plans to break ground on the colleges in Feb. 2015.

In a Monday email to the Yale community, Polak formally announced a target timeline for the construction of the new residential colleges, the new Yale Biology Building and the renovation of the Hall of Graduate Studies. These projects had been delayed several times due to the financial downturn, which caused the Yale endowment to lose nearly a quarter of its value in the 2009 fiscal year. The announcement comes a week after the university received a $250 million donation toward the new residential colleges — the largest gift in Yale history.

Polak said the two new residential colleges are scheduled to be completed in Aug. 2017, while the Yale Biology Building — which will replace Kline Biology Tower — will be finished exactly two years later. The renovation for the Hall of Graduate Studies will wrap up in late 2019.

“I think that obviously everybody would like to be moving faster, but we have to be realistic and up front about the constraints facing us — namely, the ability to raise the remaining money and to solve our budget problem,” Polak told the News.

Polak said the target dates for the new residential colleges and the biology building were a function of the time the administration predicts it will take for the University to secure the necessary funding.

The new residential colleges, which will be entirely gift-funded, still require the University to either raise an additional $80 million or cut the costs of the buildings, Polak said in the email.

Polak told the News the university will have to borrow money to fund the construction of the biology building because administrators do not anticipate being able to raise the funds through donations. Before Yale takes on additional debt, Polak said he wants to make room in the operating budget so the University can afford the extra interest payments.

“If I thought we could afford it in the operating budget sooner, I would have used an earlier date,” he said. “The main reason I put a starting date as late as 2017 is I want to be confident we can get there in the operating budget — I don’t want to promise people things we can’t do.”

Faculty members interviewed responded positively to the announcement, adding that new biology facilities are needed improvements to the university’s infrastructure.

Biology professors interviewed said the new building will not only offer better laboratory space but will also increase faculty retention and improve recruitment for both graduate students and professors.

Ronald Breaker, chair of the Molecular, Cellular and Developmental Biology Department, said that the new building will make Yale a more attractive research institution to aspiring scientists. The current facilities, plagued by malfunctioning elevators and water leaks, are not suited to modern research, he said.

Science professors interviewed said a new building has been desperately needed for some time and has been repeatedly postponed by the University.

“We have been promised various dates of completion in the past, none of which were fulfilled,” biology professor Sidney Altman said in a Monday email. “Provost Polak has been concrete in what he plans to do and I hope he will come through on the date for the YBB. Six years from now is a long time.”

Student reactions to the news of the Yale Biology Building and the new residential colleges were mixed.

Renita Heng ’16, an astrophysics major, viewed the new biology building as an unnecessary addition to the school.

“Kline Biology Tower is a thing — why do they need another? I mean, it’s twelve stories, there’s a lot of room for biology in that tower,” Heng said.

While some students said they supported the new residential colleges because the resulting growth of the undergraduate population will increase the student body’s diversity and make Yale more accessible to qualified candidates, others said they were conflicted about the new colleges because of their distant location — between Prospect, Canal and Sachem Streets — and because of the impending rise in Yale’s admission rate.

Political science professor David Cameron said Yale will have to increase classroom space and hire more faculty to meet the rising number of students.

“If you look at the students who we don’t admit who are qualified but aren’t able to come because of the restricted number of places — there are incredibly talented students out there from all kinds of backgrounds,” Polak told the News last week. “Admitting 200 more a year — that’s pretty good.”

The $250 million donation from Charles Johnson ’54 was announced on Sept. 30.