The finding contradicts the common perception that the neighborhoods are so damaged that they need to be rebuilt from scratch, said urban planners who conducted the survey.
"The structural integrity of the buildings, even in the most devastated areas, are in much better condition than has been reported," said Kenneth Reardon, chair of Cornell University's city and regional planning department.
Urban planners and students at Cornell, Columbia University and the University of Illinois carried out the survey, which was sponsored by ACORN, a national group that works to improve poor and moderate-income neighborhoods. The findings were released Saturday.
The only section needing to be rebuilt lies directly next to the levee breach on the Industrial Canal, an area that covers less than 1 square mile in the Lower 9th Ward, the survey found. Homes there were battered by flood waters of Katrina and later from Hurricane Rita.
The survey found that more than 80 percent of the 9th Ward structures "suffered no terminal structural damage" and that the majority of those structures were built atop piers, making it easier to raise them to meet new flood zone requirements.
Researchers and structural engineers based their assessment on the inspection of about 3,000 buildings.
Yet, the neighborhoods are being repopulated very slowly because of the bureaucratic and financial hurdles residents face, the survey concluded after interviewing hundreds of residents. Only about 20 percent of the residents have returned home, the survey found.
"That data shows that it can be rebuilt, and rebuilt in a cost effective way. What is lacking are the resources," said Andrew Rumbach, a Cornell planner.
Many people in the 9th Ward did not have flood insurance, and government rebuilding aid has been slow. A lack of schools, day-care centers, businesses and public services, as well as high rents, also are keeping people away.
Vanessa Gueringer, the chairwoman of ACORN's Lower 9th Ward chapter, said it may take "shaming, embarrassing" public officials to get the necessary resources to rebuild. "It may even take marching on the Capitol, and on state government."
Ceeon Quiett, a spokeswoman for Mayor Ray Nagin, said the mayor's office has not reviewed the ACORN report but will.
"We encourage and are glad the citizens are taking part," she said, adding that the mayor is interested in rebuilding the 9th Ward, a central part of the city.
John Beckman, an urban planner who has worked on rebuilding plans for Mayor Ray Nagin, said a host of factors should be considered before declaring an area ready to be rebuilt, such as an area's history of flooding and the cash-strapped city's ability to provide essential services.