"I couldn't believe it was happening," Allen said. "It was a shock that you couldn't take in until afterward."
Water came through ceilings and covered floors in Allen's office, in the vestibule outside the library, and in the museum. Text and image panels in the African American history exhibit, "Carrying the Gospel of Freedom," in Pomona Hall, were damaged.
But miraculously, the water missed thousands of documents, books, and relics, officials said. Only a Thomas A. Edison phonograph and vintage RCA projector were wet. "We're lucky we didn't have more water in other places," Allen said.
The society will be closed for repairs and maintenance until about April, when it's expected to be "fully functional" and reopen with a special event, said Chris Perks, president of the society.
The research library is open by appointment while the repairs continue.
"We're still trying to figure out what repairs we can afford," said Perks, who has been monitoring the work progress. "We still have a way to go before the repairs are finished, a long way to go."
Insurance will pay for some of the expenses, but officials hope to raise funds through donations and grants for the replacement of the heating system and other needs.
The site's closure "allows us to take another look at the museum," said Allen. "I want it to reflect the people of Camden County.
"Even though the flood was a terrible thing, it offers us an opportunity to reevaluate what we're exhibiting and the story we're trying to tell," he said. "The museum needs a redesign."
The society, founded in 1899, is a private, nonprofit organization that collects, preserves, and presents documents and artifacts detailing the history of Camden County and South Jersey.
The society's three-building complex is in the 1900 block of Park Boulevard. The group was awarded more than $200,000 in October to replace the cedar-shingle roof of the Georgian Colonial Pomona Hall.
The mansion was home to descendants of William Cooper, the first European settler in what today is Camden. Built in 1726 by Joseph Cooper Jr., and doubled in size in 1788 by nephew Marmaduke Cooper, it was the centerpiece of a 412-acre plantation worked by slaves.
During the flooding, water damaged an exhibit area on the second floor of the house and passed through a ceiling into a kitchen where slaves once labored.
At the time of the heating system's breakdown, the site was already undergoing mold remediation and was to have been closed until February or March, officials said.
"No one had been there between Dec. 30 and Jan. 7, when I came in to make sure everything was OK," Allen said.
"The heat wasn't working," said William Roulett, the society's education and interpretive director. "It was in the 50s in the building."
The boiler "was on, but the pump wasn't working," said Perks. After it was repaired, "we had seven, eight, nine leaks.
"We were still finding them a week later," he said. "The pipes had started to pop."
The water "is gone now, pipes are replaced, and the place has been stabilized," Allen said. "We're now doing ductwork in the Camden County Museum."
But the process of returning the buildings to normal will take time - and funding.
"We have to raise money to replace the heating system and just try to get by with the boiler until spring," Allen said. "Hopefully, we will replace it by the summer."
Donations can be sent to the Camden County Historical Society, Box 378, Collingswood, N.J. 08108.