Mar 10, 2021

How to Preserve Water-Soaked Books and Papers in an Emergency

Hurricane season will be upon us in a few months. Melting snow will cause some major flooding even before that, typically in March or April. We should learn from the experiences of past storms. Recent hurricanes and flooding taught all of us again that paper is a very fragile storage medium for old records. However, paper is also the most common storage method in use today. The news reports from last year’s hurricanes told of numerous libraries, public records offices, and more that had water in their offices. In some cases, the water reached records that should be saved for centuries. Many families also lost family documents, old photos, and even examples of their children’s art work. Unfortunately, water-soaked paper documents will only last for a few days unless treated immediately.

For the best-known loss of records by water damage, ask the U.S. Census Bureau about water-soaked documents. Most U.S. genealogists have been told that the 1890 census records was “destroyed by fire” in 1921. In fact, the fire damaged only a small percentage of the records. Far more damage was caused by the firehoses of the fire department called in to battle the blaze. Most of the damage was caused by water being poured onto the fire, water that soon seeped into millions of otherwise undamaged records. The fire did not go above the basement but water poured into the upper floors drained into the basement, extinguishing the fire. Unfortunately, in the process of water draining through the upper floors, a high percentage of the otherwise undamaged documents became soaked with water.

Disaster planning and recovery were almost unknown in 1921. Nobody had the proper equipment to salvage water-soaked paper documents. Once the flames were extinguished, everyone went home except for the night watchmen on patrol. No immediate effort was made to preserve the water-soaked documents. The following morning, Census Director Sam Rogers reported the extensive damage to the 1890 schedules, estimating 25 percent destroyed, with 50 percent of the remainder damaged (but not destroyed) by water, smoke, and fire.

The records sat and gathered mildew for thirteen years. Even though only 25 percent of the census records had been destroyed in the fire, all the records were eventually destroyed by Department of Commerce personnel in 1934 or 1935. (The exact date apparently was never recorded.) You can read more about the fate of the 1890 U.S. census on the National Archives’ web site at

Whether water-soaked by firemen or by a tropical storm or even by a burst water pipe, today’s technology can usually save water-soaked documents. This is equally true for a major collection of government records that fills a warehouse or for a shoebox full of important family papers, stored in a closet below the upstairs bathroom. A genealogist who knows what prompt actions need to be taken can quickly act to minimize the damage. The key word here is “prompt.” Any delay can result in far more damage than is necessary.

First Things First

The first thing to do after paper documents become waterlogged is to freeze the records. Freezing a large warehouse full of documents can be a challenge. Commercial food storage freezers have been pressed into use in the past. However, the typical home owner with a small collection of documents often has a perfect preservation tool nearby: a home freezer. Place the water-damaged documents into a freezer IMMEDIATELY.

This may be difficult to do if the electricity is off following a hurricane. Some well-prepared homeowners keep electric generators in order to keep home freezers and other appliances running. If the electricity is off in your home, place the water damaged documents into the freezer as soon as possible after power is restored.

If there is not enough room in your own freezer, “borrow” space in the freezers of friends and neighbors. For a really large collection, ask the local grocery store if they have room to store documents for a few days. In some cases, a refrigerator-freezer trailer with an attached 18-wheeler can be pressed into service.

If inadequate space is found, call the local fire department. The fire officials always know where the large freezers are located and they also will usually know which major corporations in the area already have well-defined disaster recovery plans. Those companies probably have already identified high-capacity freezers in the area that can be pressed into service, if needed. The fire department also probably has the names, addresses, and telephone numbers of nearby companies with large freezers.

Immediate freezing of paper documents inhibits mold growth. It also provides time to determine if the originals are important and worth the effort and finances to repair. If nothing else, frozen documents can later be separated into two piles: (1.) those worth saving and (2.) those that can be thrown away.

If freezers had been widely available in 1921, we all could be reading the 1890 census records today.

Freezing also provides time to review insurance policies.

Frozen documents can be left in their frozen state for months, if necessary, giving the document owners time to work with insurance companies, create an action plan, and prepare for preservation efforts.

Never freeze audio or video tapes, computer tapes, disks, compact discs, or CD-ROM disks. Freezing them will induce more damage. These recordings should be rinsed with clean water (only if the items have been contaminated with dirt and debris) and then air dried. Photographs may be preserved but techniques are somewhat different; this article will only address the salvage and preservation of paper.

Recovery and Preservation

Freezing is important as it buys time. However, freezing alone does not preserve damaged documents. An action plan is needed to later remove the water in a manner that minimizes long-term damage.

The action plan to salvage documents depends heavily upon the water that caused the damage. Was it clear drinking water, such as that from a typical burst water pipe? Or was it a mix of water, dirt, and other contaminants as typically produced by a tropical storm or a flood? Worst of all, is it salt water?

In almost all cases, the individual home owner does not have the necessary equipment or experience to salvage documents. Professional assistance is strongly recommended.

If the water is only contaminated by rust, dirt, or salt water, rinsing wet books and records before freezing helps by removing debris that could be difficult to clean off after drying. However, do not rinse any paper where the inks are soluble; instead, freeze those documents immediately, mud and all.

Professionals will usually thaw the books in small batches at a time and then start rinsing them with clean water. Often a “bucket brigade” is established, where books are dipped into a series of water-filled buckets or other containers, each containing successively cleaner water. This will remove much of the surface debris. As the buckets become contaminated with mud and debris from the books, each bucket is drained, rinsed, and refilled with clean water.

If individual pages are mud-covered, professionals will usually rinse them by supporting the records on a piece of plexiglass or other rigid, inert support, and rinse with a gentle stream of water from a hose or pitcher.

At this point, the books and papers have been cleaned of mud and other debris, but are still wet. Materials can be re-frozen and remain in the freezer indefinitely and will eventually dry there. However, that process may require months or even years. Not only is that inconvenient, the required space may not be available that long. Most professionals will use one of two methods to remove water: air drying and vacuum freeze drying.

Air Drying

Air drying is the most common method of dealing with water-damaged books and records. Because it requires no special equipment, it is often believed to be the more inexpensive method of drying. However, air drying is labor intensive, requiring constant, even round-the-clock, monitoring of the process. It also usually results in a distorted finished product. In other words, the page(s) will always look as if it has been underwater and the page will soon turn brittle. Due to the time required for air drying, it is also not unusual for mold to re-develop during air drying large-scale operations.

Air drying is most suitable for a small numbers of records. The best method is to remove only a small batch of paper documents from the freezer at any one time. Records with water-sensitive ink or paper should be left in the freezer as long as possible or vacuum freeze dried.

To air dry documents, find a dry, secure space where controlled temperature and humidity are available. Thaw out small groups of records at a time, starting with the records of least value. Experiment with lower-value documents until the process is working, then move on to the higher-valued documents. Reduce the relative humidity as low as you possible to prevent mold growth and improve drying conditions. Never apply heat. Cover tables, non-carpeted floors, or other flat surfaces with unprinted newsprint, blotting paper, or paper towels, and hang the paper documents on clotheslines. Keep the air moving at all times using fans in the drying area. This will accelerate the drying process and discourage mold growth. Aim fans into the air rather than directly at drying records. The fans are used to remove humidity from the room, not to blow air on the documents.

Carefully separate the frozen records as they thaw. If the paper is stable or strong, you can carefully peel the pages as they thaw and lay them out on your prepared surface or hang them up to dry. If the paper is fragile, you can put a support sheet of Hollytex (see or Reemay (an open-weave spun polyester fabric) (see on the top document and carefully peel the single item back. Move the single document on its support to the drying space and lay face down. Take the support sheet back to remove the next document. If you encounter any resistance as you are separating a leaf, stop. Resistance indicates that the paper is still frozen and damage will occur if you continue.

If work on a group of items cannot be finished in time, the items can go back in the freezer until time is available.

Once completely dry, records may be rehoused in clean folders and boxes, or they may be digitized, photocopied or reformatted in other ways. In fact, now is a perfect time to digitally scan all documents as there is an excellent chance that not all of them will survive the preservation process. Scan now while they are still readable!

Vacuum Freeze Drying

Vacuum freeze drying is the best way to remove water. It is also the only practical method of preserving print when the documents were printed with water-soluble inks, such as inks used in most inkjet printers. However, the required vacuum equipment is not commonly found outside of specialized preservation centers. A local high school’s science lab may have a vacuum pump capable of removing water from a small stack of papers or from a single book. However, vacuum pumps capable of removing water from larger collections are very large, very heavy, and very expensive.

Frozen books and records are placed in a vacuum chamber without thawing them first. A vacuum is pulled and a source of heat introduced while the overall temperature remains below 32° F. The materials are dried by a process called sublimation: the water in the solid phase (ice) is removed from the materials in the gaseous phase without passing through the liquid phase. In short, the ice turns to ice crystals that then evaporate directly without becoming water first. The result is a nice, dry page with minimal water damage.

Other advantages include speed and reduced requirements for a large “drying area.” Wet documents can be placed into a vacuum pump, the water removed within a minute or two, and then the documents may be placed directly back on the shelf for long-term storage. In contrast, air-dried documents require large, dry areas for drying, as described earlier.

If materials have been stabilized quickly after becoming wet, very little extra shelf or storage space will be required when they are dry.

Although vacuum drying may initially appear to be more expensive because of the equipment required, vacuum-dried documents usually do not require rebinding while air-dried documents often do require new bindings. This can result in significant savings, sometimes enough to pay for the vacuum pumps.

In addition, mud, dirt, and/or soot are lifted to the surface during the vacuum-drying process, then easily removed with a gentle vacuum or, in the case of more delicate documents, with a soft brush.

All of the above is to be considered a “last ditch” effort. Embark on these steps only after the damage has been done. A far better plan is to make sure documents are stored in locations where water will never reach them, areas far removed from water pipes as well as from rivers and streams. However, no storage method is ever perfect as Mother Nature constantly creates new disasters not previously envisioned. The professional archivist and the individual genealogist both should plan to minimize the risk as much as possible and also to make digital copies of everything IN ADVANCE of an actual disaster. Of course, multiple copies of the digital images must be made and stored in multiple locations. Those images also need to be updated to the latest file formats and storage media every few years. Digital copies will never be as good as the originals on paper, but may suddenly become valuable when the originals are destroyed by water or by some other disaster.

As the Boy Scouts teach us, “Be Prepared.”

For further information, you might want to read Preserving Family Collections: A Workshop Manual by Clement Bautista and Gina Vergara-Bautista, published by the Filipino-American Historical Society of Hawaii and available as a PDF file at