"Ten years after the storm, they are struggling more than you can imagine," Zach Rosenberg tells PEOPLE
Credit: St. Bernard Project

When thousands of people fled New Orleans after Hurricane Katrina hit in August 2005, one married couple from Washington, D.C., arrived to volunteer – and never looked back.

Liz McCartney and Zack Rosenburg got in their car in February 2006 to see what they could do to help the storm-ravaged city.

“We decided to make the 17-hour drive,” McCartney, 43, tells PEOPLE. “But as we drove, I started asking myself, ‘How bad it could really be?’ ”

It didn’t take long for those doubts to fly out her car window.

“I was completely shocked and deeply saddened by what I saw because it was much worse than anything I ever could prepared for,” she says. “They needed so much help.”

The people they started to help on their trip, which was originally planned for just two weeks, reminded them of their families.

“These homeowners who lost their homes in the storm were successful people. They had been taught since they were young to work hard, buy a home and things couldn t get too bad,” Rosenburg, 42, tells PEOPLE. “But now they were living in FEMA trailers, attics, cars and garages. It soon became apparent that we couldn’t tell them, ‘Good luck, have a nice life and hang in there.’ ”

Instead of saying goodbye, they decided to make New Orleans their new and permanent home.

A New Start

The couple loved their life back in Washington, D.C. McCartney worked for a local community organization that provided after-school and summer programs, and Rosenberg was a lawyer.

“We had wonderful friends, a great place to live and Liz’s family was nearby,” Rosenberg says. “But when we came to New Orleans, we knew we couldn t leave these people behind.”

They knew they wanted to help rebuild homes, so the couple hosted a fundraiser in Liz’s parents’ living room and gave her parents a strict order: Only invite people you know will donate money.

With the $20,000 that they raised, along with the first pick-up truck they ever owned and a minivan filled with tools they had no idea how to use, they started the St. Bernard Project.

“What we didn’t do is wait,” he says. “We started building houses fast and people started volunteering. We wanted to get people back on their feet.”

To date, they have built more than 950 homes and have expanded their efforts to areas damaged by Hurricane Sandy in New York City and New Jersey in 2012, as well as Joplin, Missouri, which was impacted by a deadly and destructive tornado in 2011.

There’s More to Be Done

It’s hard for McCartney and Rosenberg to celebrate their successes.

“In a way, I wish that we didn’t need to exist,” McCartney says. “In a country with so many resources and innovators, it seems like we should be able to help communities both prepare for and recover from disasters a lot faster than we do now.”

Adds Rosenburg, “We have a guy who earned a Silver Star fighting for his country waiting for us to build him a home, and he’s currently living somewhere that would be bad in a third-world country,” he says. “There has been tremendous progress in New Orleans, we have a long way to go.”

One of many people to benefit from the St. Bernard Project is Sullivan Dabney.

“I had it all and then it came crashing down,” Dabney, 70, a jazz musician in New Orleans tells PEOPLE. “But the St. Bernard Project saved me. They don t get the credit they deserve.”

Dabney remodeled his home two weeks before the hurricane hit. The storm then flooded his house, and for the next five years, he cut the grass outside, even though the house wasn’t livable.

The walls inside his new house, which he has lived in for about five years, are lined with dozens of photographs of volunteers working hard to build him a home.

“I am so thankful,” he says. “It makes me we want to help other people going through a tough time.”

Although it’s been 10 years since Katrina hit, Rosenberg says that their waitlist is the longest it’s ever been. They get 15 to 20 calls a week from people in New Orleans still trying to rebuild what they lost.

Beyond a Home

The St. Bernard Project wants to build more than just homes.

“That just feels like a band-aid,” says Rosenberg. “We also want to shorten the time between the actual disaster and the recovery.”

The couple created the Disaster and Resilience Recovery Lab, which will provide training programs that help develop resilience before disasters strike, and another program that maximizes efficiency of the rebuilding and recovery effort.

“The next person who loses their home to a storm could be your neighbor, your friend, your family,” says Rosenberg. “We help because it’s just the right thing to do.”

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