A new development near the Castro district earmarked for low-income LGBT seniors could end up with few if any gay or lesbian residents, and there’s little the city can do about it.

In a city starved for affordable housing, the 40 units under construction at 55 Laguna St., the old UC Berkeley Extension site in Hayes Valley, will go into San Francisco’s long-running housing lottery, where eligible seniors from across the city — gay and straight — will have an equal chance to move into permanent, low-cost housing.

For Seth Kilbourn of Openhouse, the lesbian, gay, bisexual and transgender-oriented nonprofit that is a co-developer of the project with Mercy Housing California, the city’s housing rules are just another hurdle in the effort to provide a supportive, affordable place where aging gays and lesbians can grow older in and near the neighborhood where they have lived.

“It’s the system we’re living in,” said Kilbourn, whose nonprofit will be moving into the remodeled Richardson Hall, where classrooms and other facilities are being converted into apartments, offices and shared space. “Now we need to do some good old community organizing to let people in the LGBT community know they’re eligible for the new housing.”

But being eligible for affordable housing is a far cry from moving in. In the past year, the Franciscan Towers at 217 Eddy St. in the Tenderloin had 2,066 applicants for 105 units. At 1100 Ocean Ave., near City College, 5,534 applications were turned in for 45 units, and there were 5,349 people seeking the 69 units at 280 Beale St., south of Market Street.

Increasing need

“The numbers are astronomical, and they’re higher this year than last year,” said Olson Lee, director of the Mayor’s Office of Housing and Community Development. “Allocating scarce resources like housing is never fun.”

With thousands of city seniors looking to grab that San Francisco brass ring of an affordable place to live, there’s no guarantee gays and lesbians will win the lottery for a spot in Richardson Hall or in the 79 additional LGBT-friendly units slated to rise by late 2018 on a parking lot next door.

To Supervisor Scott Wiener, whose district includes the Castro, that’s just wrong.

“It’s extremely important that we have LGBT seniors in those units,” said Wiener, who for years has pushed for the project, which would be the nation’s largest gay-oriented affordable housing development. The city “must make good on our promises to the community, which has worked for years to get this project built.”

LGBT seniors face “very significant and unique problems” as they age, the supervisor said. They’re less likely to have adult children they can move in with and more likely to be alienated from their families. Many lost part of their support system to the AIDS epidemic, and others have long-term disabilities from HIV/AIDS.

Wiener already has secured $220,000 in city funds for a two-year effort to inform the LGBT community about the housing lottery process and how to navigate the system. He also joined last month with fellow supervisors Julie Christensen, London Breed and Malia Cohen on legislation that would earmark 25 percent of all city-sponsored affordable housing for residents of the supervisorial district where it is located.

“The current housing lottery system is not protecting residents who need affordable housing and want to remain in their neighborhood,” Cohen said in a statement. “Too many people are being forced out because they are getting passed over in the affordable-housing lotteries.”

Tough balancing act

But while a geographical preference sounds good to people living in areas like Chinatown, Bayview and the Western Addition, where much of the city’s affordable housing is being built, it makes the lottery odds even worse for residents of the Sunset and Richmond districts and other parts of San Francisco where there is little low- and middle-income construction.

“It’s an issue we’re grappling with,” Lee said. Wiener “is trying to represent the needs of his community, but we’re trying to balance the fair-housing aspect. ... It’s a very, very difficult balancing act.”

Under federal fair-housing rules, age and income are among the few preferences allowed in apartments built all or in part with government money. San Francisco also moves people evicted under the Ellis Act or displaced by redevelopment to the front of the lottery line.

Setting units aside for gay and lesbian tenants “is not a preference we can make under the law,” Lee added. “If you have too many preferences, the general public can’t have access to these units.”

So Wiener, Kilbourn and others in the LGBT community are left to walk a narrow line, pushing to get as many gays and lesbians as possible into the new community while recognizing — and welcoming — the straight seniors who are sure to move in.

Application help

“We’re making it very clear about the community we’re creating,” Kilbourn said. “But we’re also clear that we’re working with everyone and very specific about not saying, ‘Don’t apply.’”

Although there’s no date set for when applications will be taken for the 55 Laguna development, which is scheduled to open in fall 2016, Openhouse is already holding workshops showing seniors how to apply for any and all affordable housing in the city.

“You only have to win (the housing lottery) once,” Wiener said. “If you win on your 20th try, you now have affordable housing and you’re stable in the city.”

But it’s still important to provide a place where gays and lesbians can finish their lives in the community they helped create, Wiener said.

“These are the heroes who built our community and got us where we are today,” he said. “We have an absolute obligation to create places where they can age with respect and dignity in that community.”

John Wildermuth is a San Francisco Chronicle staff writer. E-mail: jwildermuth@sfchronicle.com Twitter: @jfwildermuth