BUTLER TWP — An increase in illegal drug use in Butler County has caused the Ellen O’Brien Gaiser Center to plan an expansion.

Center Executive Director Linda Franiewski said the facility, which is a nonprofit drug and alcohol addiction treatment center, continues to see a “considerable” increase in the number of women applying for treatment through its in-patient program. The Gaiser Center also runs an outpatient facility on Liberty Street in Butler.

Township officials on Wednesday approved the proposed expansion at the Gaiser Center at 165 Old Plank Road.

The project will significantly add to the facility and allow it to separate male and female clients.

The approval came after a lengthy hearing before the township zoning hearing board, which voted to approve the 4,590 square- foot addition to the facility’s east side. The project will be a two-story building that would house female clients on its second floor, and administrative offices on the first floor.

The work will allow the center to increase the number of clients it serves from 29 to a maximum of 45, though Gaiser Center administrators say it’s more likely that the facility would top out at about 40 clients at any one time in the next five years.

Currently, Franiewski said, the center uses one of its two buildings at the facility on Old Plank Road to house both male and female patients. The patients are separated on different floors, she said, but that arrangement means the center is only able to accept eight women — a number she called inadequate.

“I think everybody knows truly what is going on in our country, not just Butler County,” Franiewski said, adding that only about 11 percent of people struggling with drug and alcohol addiction receive treatment. She said the center is dealing with a rash of heroin addictions.

The center’s inpatient program is a 90-day treatment regime, and Franiewski said that in addition to needing more space for women, it needs to expand and separate the residential facilities for both genders.

“The reality is we can’t mix the men with the women,” she said. “We’re really running into a lot of significant trauma histories. We really want to make a women’s facility; we want to carve that out.”

The expansion would allow the center, which has 13 residential rooms, to add 14, but those beds wouldn’t be immediately filled, Franiewski said. She envisions adding four female patients to the Old Plank Road facility this year, and another four next year.

In total, the facility would be licensed to house 45 patients at one time following the expansion, but that would mean adding five or six additional staff members to retain the 8-to-1 ratio of patients to staff, Franiewski said.

Following the board’s vote Wednesday, Franiewski said there is not a firm timetable on when to begin construction, but that the agency wants to move quickly on the project.