Up to 40 people were believed to be living in the Economy Motor Lodge on Tulane Avenue when a fire struck the long-abandoned property on the night of March 7. Located six blocks from the mayor's office and just down the street from the Superdome, the fire was the fourth at the boarded-up motel since hurricane Katrina. Rescue workers spent the next day searching the ashes for possible victims. None were found, though one man who had apparently slept though the blaze emerged from the building the next morning. The city has since ordered the property torn down.

Behind that four-alarm fire lies a disturbing trend: Hurricane-ravaged New Orleans faces a major crisis with homelessness. Already taxed to the breaking point on many fronts, the city has a homeless population that is now approximately double what existed before the storm – in a city half its previous size.

Facing a severe shortage of affordable housing, displaced residents returning to the city along with an influx of construction trade workers are being forced to sleep in everything from cars to flooded-out houses to long-abandoned motels, as Katrina relief workers from across the country still struggle to fill gaping holes in the city's social services.

"The vast majority of emergency shelters have not been reopened since Katrina," says Martha Kegel, executive director of UNITY, a regional collaborative of 60 agencies serving the homeless. "There's an enormous shortage of housing and people are desperate. Do we have the resources to deal with this problem? No."

While New Orleans has long struggled with poverty, the face of homelessness has changed since Katrina, Ms. Kegel and other advocates say. The population now includes the chronically homeless who never left the city or have returned; residents who lost their homes to the flood and have run out of federal assistance – or may have never received assistance – and cannot afford higher rents; and thousands of Latino workers who came to rebuild the city, many of whom brought their spouses and children and cannot find a place to live.

"I've been into some of these buildings myself and seen dozens of people living in them, including very young children," Kegel says. "One of the most shocking things we're seeing now are the very elderly who are living in abandoned buildings and on the street – people in their late 80s living this way, who never in their lives expected to be homeless."

More than 12,000 on the street each night

On any given night, more than 12,000 homeless men, women, and children need shelter in New Orleans, Kegel estimates. Before Katrina it was 6,000 a night; just a year ago it was 2,000. Her estimate does not include people living in federally provided trailers or multiple families occupying a single house.

The growing homeless population also faces a dearth of social services and a nearly complete lack of mental health care, along with rising crimes rates and the myriad other dangers that come with living on the streets.

According to homeless advocates, the city has no effectively functioning social-services agency offering case management to the homeless.

City officials say addressing the city's shortage of affordable housing hinges on state and federal funds, both of which have been slow in materializing. "Mayor [Ray] Nagin realizes that homelessness is a growing problem in New Orleans," says Pat Robinson, deputy chief for planning for the Mayor's Office of Planning and Development. "To address this, we're utilizing state and federal allocations and working with agencies such as UNITY, which are working as an extension of city government."

What little aid many of the homeless receive is being offered by grassroots volunteers who often have no experience. Brandon Darby, interim director of Katrina relief group Common Ground, says the nonprofit has taken numerous calls from the public advocacy office asking for help to find housing for homeless residents.

During one recent week, a volunteer acting as a caseworker assisted a middle-aged diabetic who was facing discharge from a local hospital with nowhere to live, a senior citizen addicted to gambling who had been living in Harrah's casino before she was turned out, and a mother who had spent weeks living in a car with her teenage son. The mother had recently moved back into her flood-damaged house in the city's hard-hit Ninth Ward when a tornado knocked it off its foundation in mid-February.

"By law the federal government was supposed to give people made homeless by Katrina 18 months of assistance, but in many, many cases that never happened," says Mr. Darby, who has set up a toll-free number so Common Ground can take calls directly from the homeless and accept donations for their support. "Many landlords will not work with people who have FEMA [Federal Emergency Management Agency] vouchers, because they're afraid FEMA will not pay. There are almost no services in this city for people with severe disabilities. Rates of mental illness have gone through the roof, but there are no psychiatric beds available.... Everyone has their own problems to deal with, and it's hard to find someone to help them."

City opens new homeless housing facility

New Orleans did mark a step of progress last month when it opened a 40-unit supportive housing facility for the homeless and disabled through a private-public partnership. "This is a great day in the city of New Orleans," Mayor Nagin said at the ribbon-cutting ceremony.

New Orleans resident Jackie Silverman, a member of Congregation Gates of Prayer Synagogue, helped establish one of the two small shelters Common Ground opened last year, providing 30 beds for the homeless. She now volunteers as a lay caseworker with other congregants from her synagogue. "We ask them where they were before the storm, where they are now, and where they want to go."

Several homeless residents in the Ninth Ward have joined Common Ground's staff, living in dorm facilities with volunteers from across the country while they await housing. Al Bass, a resident of the Lower Ninth Ward, returned four months after Katrina with nowhere to live but his flooded-out home. "I was in my house during the storm when 12 feet of water came in, and that's what I came back to," says Bass, who lived in the gutted-out property until last April.