Jefferson Apartment Group and Haverford Properties have been selected to develop the riverfront property known as Festival Pier, the Delaware River Waterfront Corp., the nonprofit group that controls the site, said Friday.

The partnership will build about 550 units of housing and 30,000 square feet of retail space as part of a plan that also will include ample public space at the site, near the intersection of Spring Garden Street and Columbus Boulevard-Delaware Avenue, the DRWC said in a statement.

The project is being designed by architect Cecil Baker & Partners and the landscape architecture firm Olin, the group said.

Friday's decision by the DRWC, which is responsible for waterfront redevelopment from Oregon to Allegheny Avenues, marks the culmination of a developer-selection process that began in February, when guidelines for the 11-acre site's transformation were published by the group.

"We are proud to partner with this team of experienced developers to anchor this key site on the central Delaware with what will be a well-designed, mixed-use development," DRWC president Tom Corcoran said in the release.

The developers also will be responsible for making geotechnical improvements to the site, which juts into the river, so it can support the planned development. The DRWC's guidelines in February estimated the cost of those improvements at $8 million.

The development team is expected to sign a sublease for the parcel by the end of the year, the DRWC said.

The site's design will be finalized soon after, following a public-comment period.

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