Drying out

This is a short piece that I reported and wrote up for the Vermont Historical Society's newsletter, History Happenings. I wanted to look at the topic given that Vermont's recovering from some catastrophic flooding, and what some of the concerns around water and humidity have on collections – and why it's important to mitigate issues before they become bigger problems. You can sign up for VHS's newsletter here.

Barre awoke to a new landscape on the morning of July 11th. The rain from the weeks before saturated the ground, and a storm the day before pushed the Stevens Branch over its banks, spilling the muddy-brown water into the streets, basements, and houses that lie next to it. The flood evoked memories of past floods: the 1992 flood in Montpelier threatened the Vermont Historical Society collections, then stored in the basement of the Pavilion Building along State Street, and prompted the organization to relocate to its present location on higher ground on Washington Street in Barre.

VHS, and all historical societies, museums, and archives, are wary of water. These organizations are charged with preserving the items that represent the past for the citizens and scholars in the future. Water is one of the most dangerous forces that confronts history. Give it a geological time span, and it'll grind mountains into silt and sand, and leave items unattended in a flood plain, and it'll saturate the objects and papers, potentially destroying them.

Kate Phillips, VHS's Librarian, notes that paper is generally resilient when soaked. "Under ideal circumstances, many papers can be dried out with few long-term consequences." But, she notes, "floods are rarely ideal circumstances. Rushing water or prolonged submersion can physically cause some kinds of paper to disintegrate into pulp." Moreover, floodwaters often carry with them silt, sand, sewage, petroleum, and other substances that can stain or destroy the objects they come into contact with.

VHS Collections Manager Teresa Green points out that when it comes to the physical items in a collection, the effects of water can vary. "Glazed ceramics and glass can potentially be harmed by minerals and other deposits in the water, but for the most part, they're ok. Metal can tarnish, rust and expand, wood can expand, warp and hold the water. Textiles are hit or miss—if they're in good, healthy condition and the dyes are water fast, they could be fine if the water is clean."

"But if the fibers have dried out (which eventually happens to all textiles) becoming wet will expand the fibers," Greene continued, "causing them to split just from the pressure of the weave, so fabric disintegrates." Like with paper, she points out, floodwaters are rarely ideal circumstances for items: the substances that they carry can cling to the fibers, and cause lasting damage.

On the morning of the 11th, VHS Director of Collections and Access Amanda Kay Gustin and PR & Guest Services Coordinator Andrew Liptak made their way to the History Center in Barre, where they found some water had made its way into the building's collections spaces. Fortunately, this wasn't the flood waters that inundated much of downtown. The building overlooks downtown Barre on a hillside, but after the heavy rains, some of that water made its way into the basement.

Those collection spaces are climate-controlled, keeping the humidity down to tolerable levels, and at cooler temperatures. The water that entered the building wasn't much: halfway up one's fingernail, but standing water can affect that ideal climate. The pair set about sucking up the water with a shop vac, set up dehumidifiers, and used mops and kitty litter to soak up as much of the water as they could. By the time they were done, the water was starting to evaporate on its own. In the days and weeks that followed, VHS deployed additional dehumidifiers, and closely monitored the temperature and humidity levels.

The initial water damage is only the start to the potential issues that come with flooding, Phillips and Greene said. The longer-term problems is mold, which can proliferate. "Humidity creates an environment where mold can flourish," Phillips explained, "this can either be the growth of new mold or the reactivation of dormant mold or mildew. It also prolongs the amount of time it takes for items to dry, thus increasing the potential for mold growth."

"Mold can permanently stain objects, weaken the structure, and damage the finish," Greene says. Another concern, the pair point out, is that mold can be hazardous to people. Breathing it in can cause serious health issues for those around it, making it imperative that any moisture is removed to prevent it from growing or spreading. Items in a collection or library are evaluated for any such risks before they're brought into the collection and sometimes require treatment before they're accessioned.

When there is water damage, whether it's water in the basement, a broken pipe, or floodwaters, collections staff work to address the underlying moisture. "We begin by assessing and documenting the damage and then prioritizing items for salvage (unique to our collections, high research use, profoundly within scope of the collection)," Phillips says. "Paper items and books need to be dried out immediately, as mold can begin to spread rapidly. We would remove any folders, mylar casings, frames, or other enclosures that would create a closed environment for mold to grow. If there is a safe, clean, and dry space to do so, we would start by laying items flat to dry. Window screens or the plastic grates from florescent lights are great surfaces for this, as they allow both sides of a sheet of paper to dry."

"For books, we blot out excess water and interleave pages with unprinted paper towels, cotton towels, or blank newsprint," she continued "If water soluble pigments are running, we isolate those pages with wax paper. If they're stable enough, books can be dried fanned out and standing on their spine. We can set up dehumidifiers and fans in the workspace in order to create an environment where the wet paper can dry quickly and consistently. If we aren't able to work quickly enough, we might freeze books to buy more time before mold sets in, or freeze sometime that has active mold growth. Once the mold is dormant, we can use various surface cleaning techniques in a well-ventilated space, done by staff wearing proper protective gear."

On the object side, Greene notes that their approach is similar. "Often, the damage will be a loss of integrity to the object's structure, which means that it may look pretty much the same as before, but it can no longer be handled or manipulated, and the examination itself will do more harm. If there is mold, you isolate the object by encasing it in plastic with as little moisture inside the plastic as possible, and then freeze it. At-home freezers aren't cold enough to kill mold spores, but they can cause them to go dormant, allowing someone to physically remove them without as much risk of spreading."

Fortunately, VHS didn't have to resort to these tactics: its collections in Barre have remained dry, kept that way by the quick efforts of staff to ensure that the water that did come in was whisked out quickly. In Montpelier, the museum was lucky enough to be situated above the high-water mark. However, the building's basement was inundated with water that went up to the ceiling, and the state already has efforts underway to dry it out (VHS didn't have anything stored there). Some of those climate control efforts extend to the museum. Following the flooding, VHS staff arrived to take humidity and temperature readings throughout the building, and found them within tolerable limits. To prevent any potential problems, the state's contractors have also been through the building and installed systems to keep the building cool and dry. It'll be a while before the museum reopens, but when it does, the artifacts on display be awaiting the visitors who return.