Raleigh, N.C. — The buzzing, grinding sound of machinery is a joyful noise on Donald Ross Drive in Raleigh, where the city has hired a company to repair damage and deterioration to the aging sidewalks.

“People seem to think (the noise) is a good trade-off to get their trip hazards removed from their sidewalks,” said Phillip Hester of Precision Safe Sidewalks, which is making the repairs.

The city has hundreds of miles of sidewalks, and a lot of them are in bad shape. Officials estimate $30 million is needed to fix them all. A 2011 transportation bond provided $4 million to repair the most dangerous problems over the next two years.

Sidewalk damage used to be the responsibility of the property owner. But that changed a few years ago, when the city took over sidewalk repairs.

“Right now, the employees I have are working six days a week,” said Chris McGee, a manager with the city’s Public Works department.

McGee said the city is four to six months behind on repairs, and his single sidewalk inspector sometimes gets 50 complaints a day.

“We should get caught up on them eventually, but we're probably looking at three to four years before we really get what I'd say was caught up,” he said.

The city’s first priority is to repair trip hazards. That’s what Hester was doing on Donald Ross Drive, where he was smoothing the concrete with a cutter designed especially for the job.

“People call in to Public Works and say, ‘Thank you for fixing the sidewalks in our area.’” he said.

Residents can report damaged sidewalks to the city online.