Gwynedd Mercy University, a small Catholic school in Montgomery County, announced Thursday that it had doubled the size of its campus by purchasing an adjacent property from Merck & Co.

The addition of the 154-acre property on Sumneytown Pike in Gwynedd Valley will increase the university’s physical footprint to 314 acres. The new site also includes a 157,000-square-foot building, which the school plans to adapt for its use.

Gwynedd Mercy paid $12.1 million for the property, which is assessed at nearly $10.6 million, according to information filed with the Montgomery County recorder of deeds.

“We are absolutely thrilled that we were able to take advantage of such a once-in-a-lifetime opportunity to purchase this prime piece of property,” university president Deanne D’Emilio said. “Some of our current facilities are bursting at the seams, and this new space will provide exciting opportunities to expand and enhance the educational programs available to new and continuing GMercyU students.”

The college was founded by the Sisters of Mercy in 1948 and became a university in 2013. It currently enrolls 2,030 undergraduates and 960 graduate students, and has roughly 20 buildings on its campus. Undergraduate enrollment has been relatively steady, said spokeswoman Meghan Orsino, but graduate enrollment has been increasing and the school has needed more building space for a while.

The university’s strategic plan calls for growth in professional and health-care programs, but D’Emilio said the school is not ready to be more specific about its plans for the property.

“We’re in the very early stages,” she said, “but we just could not pass up the opportunity to expand and grow our institution."

The university became aware that the property, which the school is now calling East Campus, was going to become available less than a year ago, she said.

It’s the school’s largest purchase of property since its founding 70 years ago, said D’Emilio, who became president a little over a year ago. The university last added a building – University Hall – in 2013. The building on the new property, largely an office facility, is three times the size of that, she said.