CHICAGO (CBS) — The city of Gary has completed a long project to survey the state of housing and other buildings, and found many are in very bad shape.

For 2 ½ years, nearly 200 volunteers walked the streets of Gary each Saturday, surveying nearly 60,000 parcels of land, and noting what they saw.

Gary Redevelopment Director Joseph van Dyk said the volunteers found nearly 7,000 vacant buildings – 6,315 abandoned homes and 554 vacant businesses. In addition, they found more than 11,500 of the city’s 31,000 residential buildings were “blighted,” as were nearly 900 of Gary’s 2,200 commercial buildings; only 43 percent of Gary’s 58,000 parcels of land have any buildings currently standing.

“One thing that really stood out to me was the number of blighted buildings that were occupied,” van Dyk said.

Gary Mayor Karen Freeman-Wilson said “What really stood out for me was the fact that you have people living in blighted property.”

RELATED: Gary Parcel Survey

The city has been working with the University of Chicago to figure out what to do with all the abandoned homes and buildings in Gary.

“Really, no city has figured it out, but it is certainly not as simple as just demolishing buildings,” said Carol Brown, program director for the Urban Revitalization Project at the U of C’s Harris School of Public Policy, and a policy chief under former Chicago Mayor Richard M. Daley. “There’s an extreme cost to demolition.”

Demolishing all the vacant buildings in Gary could cost $40 million, according to Freeman-Wilson.

Other options include rebuilding vacant homes, holding owners responsible, and possibly blocking off sections of town.

Van Dyk said Gary has great minds working on the issue.

“We have sort of an all-star team of nerds. We have these guys called geospatial econometricians, who look at the economics behind data,” he said.

Daley, now a senior fellow at the U of C, initiated the project, which uses graduate students to assist Freeman-Wilson and her administration in efforts to revitalize Gary.

Freeman-Wilson said the information gathered by the Land Parcel Survey “will allow us to add to our efforts to address the blight.”