The thwacks of golf clubs might be heard eight stories above downtown Minneapolis if a proposal floated at City Hall on Tuesday moves forward.

The privately funded plan involves building a new story atop two publicly owned downtown parking ramps near Target Field and covering it with multicolored fabric, giving it a circuslike look, based on initial renderings.

Developers envision a driving range, putting green, running track, athletic fields, event space and a youth center — all available year-round.

"A big part of this is trying to make the entire facility an oasis of summer ... in the middle of the winter," said Tim Thompson, one of the people behind Rooftop Golf LLC, which is seeking the rights to develop the property.

The idea is about 15 years old, but may finally have some traction because the owner of the larger ramp, the Minnesota Department of Transportation, has expressed openness to leasing air rights above the facility.

On Tuesday, two City Council committees authorized staff to develop agreements that would pave the way for the project.

If everything goes smoothly, the 18-month construction process could begin in 2015, said project consultant El Tinklenberg, a former state transportation commissioner.

"We want this to be a place that's fun for adults and really good for the community's children," he said Tuesday.

Developers said the project, which could cost upward of $70 million, is similar to Chelsea Piers in New York, where piers have been converted into athletic and commercial complexes. They envision space for events ranging from weddings to music performances.

The proposal would be built on two ramps adjacent to Target Center and Target Field: the city-owned Hawthorne Transportation Center and MnDOT's Ramp A.

While municipal golf courses have suffered from declining interest in recent years, developers know the downtown office core is packed with golf enthusiasts.

"I think the issues that people have lately with golf is the amount of time involved in playing a round of golf," said David Mooty, the other partner behind Rooftop Golf. "So what we would be offering them is the ability to play golf or to take part in golf on a much faster basis."

Developers have created a separate nonprofit company, Downtown Rooftop Youth Center, to oversee what they hope will be activities for young people.

"We will have classrooms, we'll have theater programs, art programs, all sorts of stuff to offer these kids," said Mooty, who owns Prestwick Golf Club in Woodbury. He said they would like to offer after-school programs and potentially even create a charter school. They are not seeking city funding to redo the ramps. But developers said they may seek some government help to support the nonprofit activities.

The project has several hurdles ahead before it can move forward. City staff eventually will return to the council with a more detailed proposal.

"We want this to be a unique part of what's great about living in, working in and visiting Minneapolis," Tinklenberg said.

Eric Roper • 612-673-1732

Twitter: @StribRoper