SAN JOSE — In the heart of Silicon Valley, renters enduring deplorable living conditions — mountains of overflowing trash, dilapidated buildings, violent crime and drug dealing — have limited options for help. For many, who consider themselves lucky to find an apartment under $2,000 a month, they can’t afford to move out and are afraid to speak up.

Amid Silicon Valley’s unprecedented housing crisis, demand for tenant assistance has soared and the organizations that help the most vulnerable renters are increasingly understaffed, overworked and underfunded — turning away hundreds of desperate renters a year.

“In such a tight housing market, landlords can easily evict someone or threaten them with eviction rather than making repairs,” said Kyra Kazantzis, an attorney at the Law Foundation of Silicon Valley. “It’s been getting worse, and I don’t see it slowing down. We have to turn people away every day, maybe a couple of people a day.”

Despite the city’s reputation as a center of innovation, tenant advocates say, San Jose is behind when it comes to giving renters the tools to fight a bad landlord. There are only a handful of agencies that do that type of work, and they’re being stretched thin. The result, tenant advocates say, is that hundreds of cases against slumlords fly under the radar as distressed renters run out of options.

The Law Foundation of Silicon Valley has a 12-member team of attorneys that fights unlawful evictions, unsafe housing conditions or harassment and discrimination cases.

Kazantzis said her team now turns away 1,000 callers a year who face eviction. The agency turns away another 150 who report unhealthy or unsafe living conditions.

“There is a huge need and not enough resources,” Kazantzis said. The firm prioritizes cases that are the most egregious — renters without water, a sewer that’s overflowing, mold, broken windows, bedbugs, and landlords who discriminate against disabilities or have rules against children.

“We have landlords who say kids can’t come outside and play, which is illegal,” she said. “A lot of the folks we represent are too afraid to complain and have been suffering for years.”

Another program, called the Responsible Landlord Engagement Initiative, administered by the Catholic Charities of Santa Clara County, empowers renters to fight back through involvement with neighborhood associations. But that two-person team is also understaffed and overworked as the demand exceeds resources.

The team accepts petitions from residents who are dealing with a problematic landlord or neighbor. Next, Jaime Angulo and Maryela Perez, who run the initiative, reach out to the property owners and request meetings. They involve the city’s Police Department, Housing Department, Code Enforcement Division and even elected officials.

Some landlords show up to the meetings, and some don’t. Some agree to clean up their properties and some end up in court — but the group has successfully resolved 39 cases since 2012 by building cooperation. Today, it has 27 active cases and another nine on a two-month waiting list.

The program relies on grant funding with some city dollars, but it’s not enough to hire the additional four case managers Perez says are needed to tackle all the complaints she receives.

“We can’t take anymore cases because we don’t have the people power,” Perez said.

The program, which officials believe is the first of its kind in California, has taken 66 cases since it began.

One of its worst cases was in the Hoffman-Via Monte neighborhood — nestled inside one of San Jose’s most affluent districts — but the area has historically been a magnet for illegal activity.

In 2011, rival gangs were communicating threatening messages with graffiti, garbage bins were overflowing and shattered windows went unrepaired.

“There was a building that was filled with drug dealers,” said Roger Grossenbacher, who owns a fourplex in the same neighborhood. “It got to the point where rival gangs were shooting at each other. We tried getting in touch with the owner and it went nowhere. That’s why we called Jaime.”

Within months of engaging the landlords, Angulo said, emergency repairs were made, trash was removed and crime went down.

Councilman Johnny Khamis, whose district includes Hoffman-Via Monte, has been championing changes in the troubled neighborhood since he took office three years ago. He increased activity by launching an association for both renters and landlords in the area.

“It’s gotten hugely better, and the crime has dropped 20 percent since last year,” Khamis said.

But there is still more work to do. Neighborhoods like Hoffman-Via Monte exist in every corner of San Jose, and renters are stifled by the fear of being kicked out in one of the nation’s priciest rental markets.

San Jose is one of the only major cities without a “just cause” ordinance, which requires landlords to cite reasons, such as failure to pay rent, property damage or criminal activity, before evicting tenants. But as housing and homeless issues rise to the top of nearly every City Council agenda, some progress is being made at City Hall.

By the end of the year, San Jose will have an anti-retaliation ordinance that protects renters from being kicked out after reporting code violations. The city’s housing department is also looking at hiring an attorney to fight slumlords and launching a voluntary citywide mediation program to resolve problems between landlords and renters.

But some property owners say measures like a just cause ordinance only hurt efforts to clean up bad neighborhoods because it can make it harder to kick out problem tenants.

“We have to accept the fact that in bad neighborhoods there will be some bad people living there,” said Tom Scott of Cambridge Management Co., which manages 1,000 units in San Jose. “A landlord has to be able to get rid of those people.”

Contact Ramona Giwargis at 408-920-5705. Follow her at Twitter.com/ramonagiwargis.