Architect Cecil Baker has learned to stop worrying and love aboveground parking. Or at least accept it.

Baker has included a three-story parking structure in his design for two soaring residential towers proposed between Third and Fourth Streets on Callowhill Street that the Northern Liberties Neighborhood Association plans to review Monday night.

It's a shift for the designer, known for the studious takedowns of car-centric development he delivers from his seat on Philadelphia's Civic Design Review board.

In an interview, Baker said he aims to make the project a major catalyst for development in the unrevitalized district between Old City and Northern Liberties.

The parking decks are a needed concession, he said, for the success of a project that could help pave the way for a pedestrian-friendly future in a part of central Philadelphia still highly auto-dependent.

"There was the challenge of relinking the city, and that led to the idea of more density," Baker said. "Our charge was to get density, to get activity on Fourth Street, to rekindle life on Willow Street, and to make Callowhill ultimately a pleasing gateway to the city."

The project, called 4th + Callowhill, takes advantage of legislation passed late last year that rezoned the area bounded by Second, Sixth, Spring Garden, and Callowhill Streets from industrial to mixed use. The idea was to restore street life to a district of parking lots, industrial buildings, and strip-center retail by injecting residential density.

The towers get their height - 24 and 27 stories - from bonuses in the rezoning statute that allow projects with stormwater-management infrastructure, open space, and other traits to include extra units.

Paul Levy, president of the Center City District business association, said the towers would encourage spillover from Old City to the south and Northern Liberties to the north by serving as a visual draw.

"It will be a landmark," he said. "It will have a connecting effect that's very important."

Plans call for 454 residential units, 233 parking spots on four levels (one underground), 5,000 square feet of ground-floor retail, and a sprawling public green space that filters water into a drainage tunnel running through the area.

Mark Rubin, owner and developer of the site that now accommodates parking lots and a five-story office building, said he had not determined how many units will be rentals and how many will be for sale.

The main entrance would face Willow Street, a narrow, winding thoroughfare north of traffic-choked Callowhill, seen as a future neighborhood main street if development takes off.

"We are trying to create a new neighborhood," Rubin said. "Right now, it's a no-man's land at night, but this will change that."

Rubin, who owns seven more properties in the immediate area, said he was negotiating with potential co-developers for 4th + Callowhill who have experience with similar large multifamily projects, because his background is in smaller-scale renovations.

For Baker, the project has required a different plan for parking than the underground approach he was able to deploy at other big residential ventures, such as the 500 Walnut and One Riverside condo buildings.

Rubin's potential co-developers and financial backers said ample parking was a vital selling point, given the project's location beside a major highway and the lack of amenities within easy walking distance.

Since more than one level of below-grade parking would have impeded the drainage tunnel, Baker said, he was forced to design the aboveground garage. The upside was a pool deck atop the parking structure with views unbroken by the Vine Street Expressway.

The sides of the parking structure, meanwhile, are exposed to the street only on Callowhill, opposite an expressway overpass, with its three other edges set within the residential towers.

"I've always pushed developers to push their cars below grade" as a Civic Design Review board member, Baker acknowledged. "Here, we tucked the cars where they would have the least impact on street life."

215-854-2615 @jacobadelman