Westerly — Westerly Hospital celebrated the opening Friday of a $4.8 million inpatient geriatric psychiatric unit, the first facility of its kind in Rhode Island’s Washington County.

The 18-bed unit will provide care for patients 55 and older with a primary diagnosis of depression, dementia and psychiatric illnesses.

“We’ve been committed to this since Day One,” said Patrick Green, the hospital’s president and chief executive officer, referring to the hospital's 2016 affiliation with the Yale New Haven Health System, which also absorbed Lawrence + Memorial Hospital in New London.

Lawrence +Memorial had acquired Westerly Hospital in 2013.

Green, addressing a gathering of Yale New Haven Health executives, Westerly Hospital board members, medical staff and state and local officials, said a Community Health Assessment completed soon after the affiliation revealed the need for an inpatient geriatric psychiatric facility in the area.

Over the next five years, Washington County’s 55-and-over population is expected to grow nearly 9 percent, from 45,331 to 49,287 people, according to information supplied by an L+M spokesman. During the same period, inpatient discharges of patients 60 and older are projected to increase by 22 percent.

The next closest geriatric psychiatric services are clustered in Providence, more than 40 miles from Westerly Hospital.

“The word I keep coming up with for this is ‘stunning,’” Stephen Greene, chairman of Westerly Hospital's board of directors, said of the new facility. He said his mother had been born “right here” in 1927, and that he and his children also had been born in the hospital.

Westerly Hospital has a long history of “meeting needs,” a tradition the new facility will continue, Greene said.

Michael Holmes, a senior vice president at Yale New Haven Hospital, and Dr. Peter Morgan, Yale New Haven's regional medical director for psychiatry, joined Green, Greene and a half-dozen others in a ceremonial ribbon-cutting.

The new unit, built in space formerly occupied by a women’s health center and other offices, comprises more than 10,000 square feet and includes, in addition to patients’ rooms, a dining area, examination rooms, a group therapy room, a room for private consultations and a nurses’ station.

Michael O’Farrell, a hospital spokesman, said patients could be admitted to the facility from elsewhere in the hospital, including the emergency room, as well as from other facilities in the region, including L+M Hospital.

A/Z Corp. of North Stonington was the general contractor for the project. Construction began in February.

b.hallenbeck@theday.com