New London ― About a year after the new U.S. Custom House opened on Bank Street in 1833, water began infiltrating down into the three-story, granite building.

“According to letters we have from that era, workers mentioned collecting buckets to catch the water,” said Susan Tamulevich, executive director of the New London Maritime Society. “The design of the roof wasn’t right from the get-go; it was not built to deal with New England winters.”

More than 190 years later, staff at the building, now the Custom House Maritime Museum, still get nervous whenever bad weather is forecast.

“You just don’t know what’s coming next, what it’s going to look like in the morning after a big storm,” Tamulevich said on Wednesday from inside the museum’s gift shop, where large flakes of plaster peeled away from ceiling corners. “But we’re going to fix this once and for all.”

The society, which was granted use of the custom house in the 1970s, is looking to raise up to $425,000 in donations to help address long-standing roof and gutter issues that have recently worsened.

A major December storm further strained the museum's failing roof, allowing streams of water to occasionally pour past plywood attic supports and into second-floor exhibit areas before continuing down walls and into lower floors.

Several second-floor rooms remained roped-off this week, including the custom service office where a clear tarp was draped protectively over a pile of books.

On a stairwell leading to a ground-floor exhibit room ― also showing signs of ceiling water damage ― sections of a recently re-plastered wall bubbled out where rain had worked its way through.

Even before the damaging December storm, the society had planned to embark on a major roof and gutter renovation capital campaign project.

“We felt we had a couple of years to get this work done, until the December damage,” Tamulevich said. “Now we need to raise money to get a temporary roof fix in place, as well as for the permanent work.”

Roofing experts will be at the building next week to evaluate the damage and provide costs for stop-gap repairs, which Tamulevich expects will come in at between $42,000 and $125,000.

“We want to get that work done before the main hurricane season hits in the next couple of months,” she said. “That temporary repair will buy us several years until the long-term work can be complete.”

For the roughly $600,000 needed to cover permanent repair costs, the society plans to use $165,000 already donated by the Frank Loomis Palmer Fund and an expected matching state grant.

“For the remainder of the costs, we’re going to offer naming opportunities at the museum, for things such as our flagpole and roof platform, and seek out other grants,” Tamulevich said.

Anyone interested in making a donation to the society can call the museum at (860) 447-2501.

In a March state grant application, the society documented the “constant series of repairs” required over the years to fix water-damaged plaster walls and ceilings.

“In recent years, in fact, there has rarely been a time when scaffolding was not in place somewhere in the building,” the application states, noting the December storm made the situation more perilous. “We are at a crisis point.”

j.penney@theday.com