In what is being described as the beginning of a long fight, members of Southeast Mission Geriatric Services and the Service Employees International Union (SEIU) held a demonstration on Thursday to oppose the city health department’s decision to close the geriatric center, located in Bernal Heights.

“They don’t get to make these decision without community input,” said SEIU field director Leah Berlanga. “This is just the beginning of our fight.”

The closure would be disruptive for the more than 260 low-income seniors and an additional 150 youth, creating more instability in already vulnerable populations, center staff said. The center, at 3905 Mission Street, provides psychiatric services and case management to people from the Mission, Bernal Heights, the Excelsior and surrounding neighborhoods.

The San Francisco Department of Public Health is proposing to relocate staff and services from the center to the Mission Mental Health Clinic and the Silver Avenue Family Health Center — a move that would save the department $350,000 in general fund money. The general fund deficit is expected to be $480 million in the coming fiscal year.

Health department staff did not immediately respond to a request for comment.

In 2009 the health department was on the verge of closing the center, but actions by the center’s staff and a push from the Board of Supervisors kept it open.

“Over the past several years, Community Behavioral Health Services has made an effort to consolidate leases to promote integration, create operational efficiencies and to achieve budget savings,” reads the health department’s proposal to close the center.

But such a move is misguided because the change could be devastating for seniors, said Sarah Richmond, a social worker at the center.

The center’s staff is most concerned about the relocation of seniors to the Mission Mental Health Clinic at 2712 Mission Street, between 23rd and 24th streets. They worry that the mental health clinic does not have enough staff, would not be quiet and safe, and that seniors would share a waiting room with the clinic’s other clients.

The Mission Mental Health Clinic provides an array of mental health services, mainly to adult clients. Some have a history of violence and substance abuse.

“We may see people with the same diagnosis, but for whatever reason, at a drop-in environment it’s more of a chaotic, unsafe environment,” Richmond said. “It’s an adult mental health clinic, and with that they are more potentially acute for violent substance abuse. A sheriff is there in case things get out of control.”

In contrast, Southeast Mission Geriatric Services specializes in helping seniors and is more quiet, Richmond said.

“It feels like the seniors are going to be lost in the shuffle or intimidated by some of the other people,” she said.

Staff at the geriatric center also raised issues with the health department’s justifications for the move, including that the office’s lease is month-to-month and that it is not ADA-accessible. The month-to-month arrangement is the city’s choice, landlord Dino Diodati said, as he is willing to arrange a longer lease but the city declined.

The building is also ADA-compliant, Diodati said. Its front door is button-activated, and building inspection permits show that the landlord added accessible bathrooms and installed accessible sink cabinets in 2009.

At the demonstration in front of the center, Al Fernandez, chair of the Northern California Latino Caucus, gave the 20 or so people in attendance a sign of things to come.

“We are going to take this all the way to mayor’s office,” he said. “We are going to come out swinging.”