After languishing on the other side of Interstate 95 from Philadelphia for decades, the Delaware River waterfront has become a hotbed of development.

A joint venture of Jefferson Apartment Group and Haverford Properties broke ground this week on the long-awaited development of the former Festival Pier outdoor concert venue after securing construction financing and a ground lease for the site, the companies announced on Tuesday. The JV's plan calls for 470 multifamily units split between two mid-rise apartment buildings and a series of build-to-rent townhomes, joined by 45K SF of retail anchored by a Sprouts Farmers Market grocery store.

JAG and Haverford leased the land at 501 North Columbus Blvd. from the Delaware River Waterfront Corp., the nonprofit that stewards the publicly owned portions of land adjacent to the river that provides Philly's eastern border. At around the same time, the JV obtained construction financing from Citizens Bank and Santander, the announcement stated.

The development's first phase will include a public plaza designed to connect the waterfront to the Northern Liberties neighborhood via Spring Garden Street, which currently terminates across the street from the site. It represents one of several concurrent attempts to better connect the city with the Delaware, with New York-based The Durst Organization in the planning phase for developments at multiple sites to the south of the former Festival Pier and two public space projects, Race Street Pier and Cherry Street Pier, built in the last decade.

About a mile to the north, Lubert-Adler Real Estate Funds is underway on its redevelopment of a former power plant at the edge of the Fishtown neighborhood, with similar goals to JAG and Haverford's project. Just north of that is an ongoing, more than 1,000-unit residential development called Northbank in the Port Richmond neighborhood, where some for-sale townhomes have already delivered ahead of planned multifamily and public space portions.

"The waterfront’s time has come, and we are excited to contribute to it," Haverford Properties founder and President Charles Houder said in a statement accompanying the announcement.

The city's signature waterfront initiative, the capping of I-95 and Columbus Boulevard between Chestnut and Walnut streets with a park, is still in the planning phase, and construction has been delayed several times.

CORRECTION, MARCH 24, 10:15 A.M. ET: A previous version of this article misstated the sources of construction financing. This article has been updated.