In August 2002 the world watched as floodwaters poured across central Europe, causing hundreds of millions of dollars worth of damage, displacing hundreds of thousands of residents, and submerging centuries of cultural treasures.
Among the cities worst hit by the floods was Prague, capital of the Czech Republic. The area around the Vltava River had been settled for thousands of years even before Prague became an important European center in the fourteenth century. Some of its most famous landmarks, including the Charles Bridge and St. Vitus Cathedral, date from that period. The intervening years have seen many floods, but few as powerful as the deluge of last August. The 1890 flood had topped the list since record keeping began, but last year the waters rose higher and flowed faster. In 1890, three arches of the medieval Charles Bridges collapsed from the floods. Last August, crowds gathered anxiously on dry spots near the bridge, concerned that it would happen again. A crane stationed on the bridge pushed the larger pieces of flotsam and jetsam away from the piers and the structure held this time. In Prague’s medieval quarter, a thirteenth-century synagogue filled with water, imperiling its contents and its structure. Floodwaters even reached the archives of the former Nazi prison of Terezinstadt, outside the city. The Czech government estimates that the water level on August 14 was almost twenty-four feet above the river’s usual height.
The Municipal Library of Prague and the Architectural Archives of the National Technical Museum were also hard hit. In downtown Prague, sandbags outside the Municipal Library could not protect it from infiltrating groundwater. Its two basement performance halls and a lecture hall were inundated. At the National Technical Museum’s depositories in the low-lying area of Karlin, floodwater filled the ground floor, engulfing historical documents, blueprints, drawings, photographic plates and negatives, and three-dimensional architectural models made from paper, wood, and metal.
In neighboring suburbs, the general collections in two of the Municipal Library’s branches, at Holesovice and Karlin, were destroyed and the premises of the Karlin branch severely damaged. More significantly, the Holesovice branch also housed the Municipal Library’s rare book collection and conservation workshop in its basement. The staff relied on official assurances that the branch was outside the flood zone. When it finally became clear that the rising waters would reach the library, it was too late to move the twenty-thousand-volume collection to higher ground.
“It is quite a colorful collection,” says Tomas Rehak, director of the Municipal Library. “Some are very special issues of books, perhaps only in small numbers. Some are signed by the authors. Among the rare documents is the 1488 Czech Bible and documents dating from four centuries ago to the twentieth century.” As soon as the water subsided, library staff began a race against time. Wet books deteriorate very quickly and are soon covered with mold. The library decided to abandon the branch’s general collection and concentrate on salvaging the rare document collection by using the best method available to them: they froze it.
Conservators say that freezing is the best recourse in such a situation. Books and documents frozen at -30 degrees centigrade will remain in a stable condition until enough equipment and staff are available to wash, dry, and restore them.
The first freezer the staff found that was large enough for the collection was familiar to Prague residents as a name printed on packages of frozen food. The owner of the freezer quickly moved out the remainder of last year’s harvest to make way for the plastic-wrapped books and prints. A larger, empty freezer was located soon afterwards and the collection was moved in. It shares the space with police records, court documents, and a variety of cultural archives.
“It was astonishing,” says Deborah Wender, director of book conservation at the Northeast Document Conservation Center in Massachusetts. Wender visited Prague last November to offer technical advice on restoring books and prints at several of the city’s cultural institutions. “There were shelves everywhere in the freezer—six-to-seven-foot-high shelves—and they were full.” Each institution only pays for its portion of the space, but even so, the cost is considerable. “Our cost for the freezer space is one million Czech crowns per year (about $33,000),” Rehak says.
The work of drying out the documents is being done at the conservation lab run by the National Library, which was not hit badly by the flooding. Its vacuum-packing machines are now the focus of restoration efforts. Rehak estimates that some two hundred to three hundred of the Municipal Library’s rare documents have already been dried and several hundred more have been moved from the freezer to the lab.
“It’s very labor-intensive and time-consuming,” says Wender of the vacuumpacking. “The conservators place blotter material on either side of a document, or between pages for rare books, and then put them into a special plastic bag. The machine creates a vacuum in the bag and then seals it. It’s a fairly oxygen-free environment inside the bag and there is also a certain amount of pressure. This prevents mold growth and also holds the item in shape. By capillary action, the moisture moves to the blotter material. They may have to redo this several times until the item is dry.”
“But even after all the items are dry, they’ll have to consider treating them,” Wender says. “Because the water was dirty and contaminated, there is a health and safety issue that may not be easy to resolve.” Contaminants from sewage, industrial wastes, and molds pose a danger not only to conservators working on the documents now, but also to researchers and members of the public who want to access the items later, she explains.
The methods for disinfecting the documents are still under discussion, Rehak says. One of the prime candidates is an ethylene oxide chamber housed at the National Archives in Prague. It can accommodate more than two hundred linear feet of documents at a time. Documents are exposed to the ethylene oxide gas for a day and then aired for a minimum of six days. Ethylene oxide’s effectiveness as a disinfectant is countered by its toxicity: it is a known human carcinogen. The equipment is state-of-the-art and designed for zero emissions, but the process remains controversial. “It hasn’t been used in the U.S. for a long time, and it’s banned in the European Union for that,” Wender says. The Czech Republic is due to join the E.U. next year.
A step in the restoration process for almost all the flood-affected items is washing. “Washing is standard practice,” explains Wender. “You take an item apart completely and rinse it in filtered water. It gets cleaner, it can increase flexibility, and it is brighter and clearer. The process washes away many pollutants and acids.”
The idea of putting paper into water isn’t as risky as it sounds. “Even when it’s dry, paper is still 7 to 10 percent water,” Wender says. “No matter how it was made, if you immerse paper and support it, it will hold its shape. Even watercolors can sometimes be washed because over time the colors can set. Of course, it’s a very quick immersion.”
In the race to recover items from the flood, not everything was accorded such gentle treatment. “At the National Technical Museum, some things were simply hosed off and left to dry on the grass,” Wender says. Almost all will require some further work, including flattening and vacuuming.
“Conservation is compromise,” Wender explains. “You have to make hard decisions. At the Municipal Library and Architectural Archives they will have to decide what they’re willing to lose to clean the items.” That may be a particularly difficult process at the library. “The Municipal Library collection has so much physical integrity to begin with that it probably makes them reluctant to take things apart to wash them.” The rare books are almost all in their original, unaltered bindings, Wender explains, but manipulation of the bindings as they dry may aid in saving both the materials and the structure.
The Municipal Library conservation staff, like the staff from several other institutions, is working in the National Library’s lab. “We weren’t properly equipped before the flood and what we had was destroyed,” says Rehak. “So we are about to sign an agreement to rent premises for our own work for five years. It is near the Ministry of Culture up in the hills, so there will be no flooding.”
The floods have focused attention on how to recover from the next such catastrophe. “The Dutch have an idea of conservation components that would be moveable by truck or plane to where they are needed,” says Wender. “There would be a freeze-dryer, a clean room, a freezer, a conservation lab for paper, and another for books. It’s a good idea. The issues are where to locate the components and who will pay for them.”
For Rehak and the staff at the Municipal Library, the challenges are more immediate. “We’re not sure we can cover the costs of this disaster with what we have. We have received money for this year and we’ll try to survive on it. But we don’t have the slightest idea how this will work out in the future.”
Donations from the international community have helped fill the gaps left in hard-pressed local budgets. “Normally the Municipal Library is funded from the city’s budget,” Rehak explains. “But it’s quite tough this year, of course, and we are not top priority.” The library has received one hundred thousand dollars from its sister city of Chicago, a grant of thirty thousand dollars from the U.S. embassy in Prague, and another twenty thousand Australian dollars ($11,600) from the Czech and Bohemian community in Australia.
“We hope to reopen our underground halls on May 1 this year,” Rehak says. Rents from the performance halls and the computer lecture hall will boost the library’s income. “And we hope to reopen the Holesovice branch in August, on the anniversary of the flood.”
Estimates of how long it will take to clean and dry the damaged collections range from decades to millennia, but the daunting challenge has not impeded the work of the conservation staff at the Municipal Library and the National Technical Museum. Both institutions have posted information about the floods on their websites, detailing the restoration work they are undertaking and the technical support and funding they need. Almost all of the Municipal Library’s fifty-four branches reopened immediately, as did the National Technical Museum.
After Wender toured the Architectural Archives in November with its director, Petr Krajci, she posed a question. “I told him, ‘You know what you need to do and you’re doing it. What else can I do?’ He replied, ‘You can encourage us.’”