The William Penn Foundation is extending its longtime role as primary benefactor of the Free Library of Philadelphia by awarding the library the biggest grant in the history of either institution.

The Free Library will receive $25 million from William Penn over three years, helping to pay for renovations at the Central Library downtown, plus the renovation and expansion of five neighborhood branches in South Philadelphia, central North Philadelphia, Logan, Tacony, and Mount Airy.

The money does not make possible a Moshe Safdie-commissioned annex long dreamed of for a plot of land just north of the library's Beaux Arts building on the Benjamin Franklin Parkway. But it will provide a physical intermediate step by establishing new flow through the current building to eventually link it with the annex, while money continues to be sought for that larger expansion.

Old storage stacks on six levels on the north side of the building will be demolished, and three new levels will replace them. On the first floor will go what the library is calling "the common," a flexible, 8,000-square-foot lobbylike space that will eventually lead into the new addition. One level below will be a center for business-building and career assistance. Below that, compact shelving will replace much of the storage capacity of the six levels of stacks, but in a much more condensed space.

William Penn's gesture aims to help bridge not just a physical space, but a financial one as well. The foundation hopes its gift to the library - which accounts for a substantial share of the foundation's giving budget for the next three years, about 8 percent - will shake loose the balance of the money needed for the expansion.

How did the foundation arrive at a figure of $25 million? "More than half the city uses the library, people from every neighborhood, every income bracket, every age. Everyone's welcome at the library," said Janet Haas, vice chair of the foundation's board of directors. "It's a big institution that touches everybody, and we wanted this to be transformative in terms of people's access. This allows us to get it started in a major way, but also to garner other resources."

"The William Penn gift is a vote of confidence," said Free Library president and director Siobhan Reardon. "It gives us the ability to deliver on our dreams and to really engage the larger philanthropic community around a project like this." Reardon said the renovations are the architectural manifestation of a recent shift in mission that concentrates on job-seekers, pre-K children, entrepreneurs and small-business owners, new Americans, people with disabilities, and consumers of medical and health-care information.

"The reality is, if you want to be all things to all people, you're going to fail," she said, noting that staff has been reconfigured to accommodate the new mandate.

Both the branch and the downtown renovations fall under a campaign the library has branded as "Building Inspiration: 21st Century Libraries," which includes not only the renovations, but also the establishment of an Innovation Fund to test new programs and services and expanded involvement with Philadelphia public schools.

This evolving institutional philosophy spoke to William Penn, whose executive director, Laura Sparks, stressed the increasing role of the library in providing literacy assistance and services for immigrants and job-seekers. She said that with schools and churches closing, "even more needs are emerging." The latest gift from William Penn shows "a commitment by the family to being in it for the long haul," Sparks said.

The total budget for renovating and outfitting the five branches is about $30 million, of which $17 million will come from the William Penn grant. The round of renovations aims to create prototype branches with more flexible spaces, rolling circulation desks, and shelves that can be moved for special events, and the establishment of services unique to each neighborhood. The five branches are the Lillian Marrero Library on West Lehigh Avenue; Logan Library on Wagner Avenue; a new community center to be added to Lovett Memorial Library on Germantown Avenue in Mount Airy; the South Philadelphia branch on Broad Street being built into a new Children's Hospital of Philadelphia building; and the Tacony Library on Torresdale Avenue.

Of the $30 million needed for the five neighborhood sites, the library has firm commitments of $25 million, with active requests pending for the remainder.

The creation of the new spaces at the Central Library is budgeted at $28.5 million, of which $8 million will come from the William Penn gift. An additional $10 million is needed to reach the goal.

Design work on the annex, to be realized by Safdie Architects, based just outside of Boston, is still at a halt as fund-raising progresses, though Safdie is the architect for the more modest imminent renovations at the Central Library. The expansion, which would someday extend the library building north across Wood Street, is estimated to be a $90 million project, said a library fund-raiser.

The latest William Penn gift exceeds the foundation's second-largest gift ever - a 1996 grant, also to the Free Library, of $18 million (though measured in inflation-adjusted terms, the earlier gift is larger, translating to $27.3 million in 2013 dollars). The 1996 grant helped pay for some level of renovations, from modest to substantial, to 52 branches, and William Penn feels it was money well spent, in no small part because it lured additional funding from foundations and government.

Said Haas: "It exceeded what we expected, and our expectations were not low."

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