When construction crews build a pedestrian park to cap I-579/Crosstown Boulevard and connect the Hill District with Downtown, they’ll set beams with a crane over an active interstate.

“That’s going to be what I see as one of the biggest challenges. We’re not closing the highway. That’s why we’ve been working very closely with PennDOT and they will be managing the project as well,” says Doug Straley, project executive for the city-county Sports & Exhibition Authority (SEA).

Construction of the trapezoid-shaped park could begin in the third quarter of 2018 and take two years to complete. The SEA and its lead engineer, HDR Engineering, are set to brief the city Planning Commission on Dec. 5 on the final land development plan for the park.

“We’re going to lay out different aspects to the park, from accessibility to sustainability, pathways, transportation — how bikes and pedestrians would move around there,” Straley says. The city Art Commission recently approved enhancements to the design done by landscape architects LaQuatra Bonci Associates.

One big change from a preliminary land development proposal, which covers 28 acres to be developed in the area, is that the 3.55-acre overpass park has moved from the corner of Centre Avenue and Washington Place to Bedford Avenue and Washington Place. In public meetings, community members suggested that re-positioning it would make the park more accessible, Straley says.

“We’re also improving the interstate traffic signal at Bigelow (Boulevard) and Chatham Street, and we’ll create an ADA (compliant) pathway across there,” says Straley. “The current pathway that goes down from Chatham Street through that tunnel to get to the USX Tower — that gets filled in, and then we’ll create an at-grade street crossing” accessible to people with disabilities.

Perspective drawing of the green space within the Lower Hill District development area. Courtesy Sports & Exhibition Authority.

The base construction cost remains $26.4 million, largely funded with federal money that includes a $19 million TIGER grant awarded last year. Democratic U.S. Rep. Mike Doyle has said the cap will create a walkable bridge “to re-knit the connections between neighborhoods that were torn apart during the 1950s and ’60s during urban renewal and the construction of the federal highway system.” Similar caps have been used in Boston and Dallas and are planned for Chicago and Austin.

Mostly level, the city-owned green space will have six rain gardens, integrated artwork that showcases the history of the Hill District, a bike-share station and spaces for performances. The SEA hasn’t raised the $6 million to $8 million it estimates will be needed to build restrooms, a pavilion stage and a water feature. The tunnel that will be removed has a mosaic by the late enamelist and sculptor Virgil Cantini that the Art Commission wants to preserve.

The park’s designers will utilize sustainable materials, dark textured paving to absorb sunlight, indirect lighting, and plantings to help filter wind. With its native trees, shrubs and grasses, the site will reduce noise from the interstate, and storm water will be treated before it’s released to the sewer system. From its signage to its sidewalks to its landscaping, the park’s design will pay homage to the African-American community that is key to the Hill District’s history.

When the park is completed, says Straley, the neighborhood will have “an active green space that enhances the city and that development area. It’s something that can be used by the community there.”