Developers say work could begin as early as this fall on the Horizon Redevelopment Project, a new housing and biotechnology research hub by the Ashley River on the Charleston peninsula.

The project is aimed at creating the hub on 22 downtown acres, between Lockwood Drive and Hagood Avenue, from Spring Street to Fishburne Street. Much of that area now is comprised of surface parking lots, with space for about 1,400 vehicles.

Michael Maher, chief operating officer of the nonprofit Horizon Project Foundation, made a presentation on the master plan for the project to the city of Charleston's Board of Architectural Review Wednesday. The board's approval isn't required for master plans, Maher said. But he wanted to give members the big picture on the project so they could better evaluate individual projects for the hub in the future.

Mack Reese from Gateway Development, the leader of the development team, said the hub will be a "24-7 mixed-use space."

The project will be developed in phases, Reese said. "It's not a next year plan or a 2016 plan. It's a 10- to 20-year plan."

The first step, which could begin this fall, would be to build a parking structure on Fishburne Street, behind the police station. Then, about 300 cars that now park in lots near the corner of Lockwood Drive and Spring Street could instead park in the new structure.

Developers then would build the first two buildings at that intersection, Reese said. The buildings would have residential, retail and restaurant space on the ground floor and research, office and lab space on the upper levels. Construction on these buildings could begin as early as next spring.

City Councilman Dudley Gregorie, who represents the district in which Horizon falls, said he thinks the project will spur economic development and create jobs.

And so far, area residents are on board with the plan. He met with members of the West Side Neighborhood Association, who were pleased to hear there was a plan to build a grocery store in Horizon, he said. The area now is a "food desert," he said.

But building in the area, which sits on the site of a former landfill, won't be easy, Maher said. Lowcounty buildings generally require pilings for stability, he said. But in Horizon, the streets and sidewalks will require pilings as well. That will make building more expensive.

Charleston Mayor Joe Riley is asking the county and the school district to add a decade to tax incentives meant to help finance the large urban redevelopment project in the downtown hospital district.

The extension of incentives known as a tax increment financing district would mean that the city, county and school district would forgo property tax revenues created by the development for an additional 10 years. Instead, the money would be used to finance work in the development area, such as new roads and sidewalks. The Horizon TIF currently expires in 2033. The county and the school district have until mid-June to decide.

Reach Diane Knich at 843-937-5491 or on Twitter at @dianeknich.