Bicyclists and runners already have separate paths from Fullerton Avenue to Ohio Street, but construction will enhance the separation this summer. View Full Caption City of Chicago

LINCOLN PARK — The separation of the Lakefront Trail between cyclists and pedestrians — a project being funded by Illinois' richest cyclist, Ken Griffin — is set to continue next month on two stretches between Fullerton Avenue and Navy Pier.

The Chicago Park District and Active Transportation Alliance joined Wednesday to host an open house seeking the final public input before work begins "as soon as they can, when construction season starts in the spring," said Kyle Whitehead, the alliance's campaign director.

The projects will create a new two-lane bike path on Lake Shore Drive between Fullerton and North Avenue, while pedestrians get the original trail refurbished with two lanes and soft shoulders closer to the lake and North Avenue Beach. Then, a new four-lane path will be completed between Oak Street and Ohio Street — two lanes for pedestrians on the lake side and two for cyclists on the Lake Shore Drive side.

This rendering shows the basic designs for the separate bike and pedestrian paths, to be found between Fullerton and North, and the four-lane concept between Oak and Ohio. View Full Caption Chicago Park District

"We're anticipating just a few months' construction," said Michael Lange, of the Park District's division of planning and development.

It's part of a grand design to provide separate tracks for pedestrians and cyclists along the entire 18 miles of the Lakefront Trail. This segment of the project was announced late last year with a $12 million donation from billionaire Ken Griffin, widely acknowledged to be the richest man in the state.

In emails released under the Freedom of Information Act, it was revealed that Griffin, a lakefront bicyclist, wrote Mayor Rahm Emanuel last year to tell him the "lakefront bike path is a disaster."

Lange cheered plans for the stretch between Fullerton and North, saying, "You really get a good, clear separation" between pedestrians and cyclists.

Heather Gleason, director of the Park District's planning division, said work on the stretch between Oak and Ohio "will be a little bit tricky."

"We're not modifying the sea wall," Lange said, so construction over the spring and summer will shift both bikes and pedestrians side to side, as in resurfacing a four-lane interstate highway.

They're basically resurfacing the pavement and designating lanes between Oak and Ohio. Construction between Fullerton and North will be more extensive, separating cyclists and pedestrians, and will call for a detour.

When construction is set to begin, both cyclists and pedestrians will be detoured at Diversey Parkway to the west side of Diversey Harbor and the Lincoln Park Lagoon, down a path typically used by runners, until reconnecting with the Lakefront Trail at the North Avenue underpass.

The plans were generally well received by the dozens who attended Wednesday's meeting, an open house held at the Lincoln Park Cultural Center, 2045 N. Lincoln Park West.

"We're excited about it," Whitehead said, "and we're glad that they involved us in the process," along with the Chicago Area Runners Association.

The south end of the stretch, at Ohio Street, will have to wait for the so-called Navy Pier flyover to be completed to continue on with the grand design for an uninterrupted, fully separated Lakefront Trail running to South Shore and beyond.