Waterford — A free-standing surgery center that will be partly owned by The William W. Backus Hospital will expand into a new building more than twice its current size.

Constitution Surgery Center East, a 7,000-square-foot facility at 174 Cross Road that provides ophthalmic and orthopedic surgery, will move into a new, 19,000-square-foot building at 140 Cross Road, according to an announcement Tuesday from Dime Bank.

The bank said it is providing financing for the “new multimillion-dollar surgery center,” although it did not specify the amount. A spokeswoman for the bank could not be reached for comment Wednesday. The surgery center also did not respond to a request for comment.

The new building will be on a 13-acre site, allowing for growth in demand for services of the 21 physicians who operate at the surgery center, according to a news release from the bank. The new building will open in September.

The bank’s announcement comes less than three weeks after the state Office of Healthcare Access approved an application from Backus to purchase a 51 percent ownership share in the surgery center. The Norwich-based hospital, which is part of the Hartford HealthCare network, would pay $16.7 million for its share of the center.

"We are very pleased to receive approval from the state Office of Health Care Access to offer surgical services to residents of southeastern Connecticut in Waterford," said Shawn Mawhiney, spokesman for Backus and Hartford HealthCare. "Now we can begin work on plans to invest in the infrastructure needed to offer the best possible healthcare experience for our patients and their loved ones with partners such as Dime Bank, and collaborate with our physician partners to offer high quality, affordable, coordinated care."

With the purchase of the surgery center and its proposed expansion, Backus and Hartford HealthCare are increasing their presence along the shoreline in the core area served by Lawrence + Memorial Hospital in New London. Also in Waterford, Backus also operates the Backus Family Health Center on Parkway South.

Beginning in 2011 as an eye surgery center, Constitution added orthopedic surgery services in 2011.

The expansion announcement also comes after the Dec. 31 closure of a nearby orthopedic practice that also had been part of the Hartford HealthCare network. The network's decision to close Backus Physician Services Orthopedic Surgery, where four orthopedic doctors provided care in the Crossroads Professional Building in Waterford, is the subject of an inquiry by state regulators. The state Office of Healthcare Access has asked Hartford HealthCare for information about the practice and its relationship to the network to determine whether the closure was carried out according to state regulations.

j.benson@theday.com