TAMPA — After months of complaints from sleep-deprived residents, City Hall is trying to figure out how to create a train horn quiet zone through Ybor City, downtown and south toward Port Tampa.

The first step: paying $90,545 to King Engineering Associates to study the problem and assemble the documentation needed to apply for grants to help pay for the work. A contract with the firm goes Thursday to the City Council for approval.

As Tampa gets more dense and urban, sound from CSX train horns bounces off buildings, especially residential towers downtown, Mayor Bob Buckhorn said Tuesday.

"They are becoming more of a nuisance to residents," he said, and have the potential to stifle growth. He described the city's move as the start of a process to evaluate what needs to be done to ease the problem.

"Definitely a step in the right direction," said Michelle Buckley, a five-year Skypoint resident and president of the Uptown Council, a neighborhood group for downtown residents. "I'm ecstatic that they're paying attention to it."

The study area would include about 65 CSX rail crossings, which would need to be upgraded so engineers could lay off the horns.

KEA would assess what work — gates, medians, signs or other measures — would be needed at each crossing. Buckhorn's staff has previously estimated the costs of creating a quiet zone at $56,000 to $285,000 per crossing.

Downtown residents say the nuisance verges on intolerable.

Within the past two weeks, Steven Nordquist sent his Skypoint landlord an email saying he will move out when his lease is up. To the email, he attached two of the 20 or so sound recordings he's made of train horns at 3 a.m.

"The one factor that is driving me out of here is the train," said Nordquist, 37. "They are so unbelievably loud. It's ear-piercing."

Along with parking, train horns are one of the two main things downtown residents complain about, Buckley said.

CSX says its engineers don't blast their horns on a whim.

"The sounding of train horns is a requirement set by the federal government," CSX Florida vice president Bob O'Malley wrote to Buckhorn this spring.

Federal rules require engineers to sound the horns 15 to 20 seconds before they reach a public crossing. O'Malley told the city he had asked his operations team to make sure CSX train horns stay within federal limits of 96 to 110 decibels.

Buckhorn learned in June that Gov. Rick Scott not only supports the controversial All Aboard Florida passenger rail project on Florida's east coast, but also agreed to include $10 million for quiet zones in the state budget.

Intrigued, Buckhorn asked his staff to find out whether the quiet zone money would be available outside of All Aboard Florida's service area.

Yes, the Florida Department of Transportation said. The grants will provide up to half the cost of creating quiet zones.

Local governments can apply for the grants after meeting requirements set by the Federal Railroad Administration. They have to submit a funding request by Oct. 15.

In awarding the grants, the FDOT plans to give extra weight to communities willing to pick up more than half the costs of the quiet zones, among other factors. State law says the FDOT will monitor crashes at crossings and will have the authority to revoke the quiet zones if they cause a "significant deterioration in safety."

Downtown, residents say relief can't come too soon.

"It would be a big, big deal," said Jeffrey Zampitella, president of the board of the Skypoint Condominium Association, which passed a resolution at its last meeting calling for the creation of a quiet zone on at least two downtown streets.