Bryan Whitledge 2017-05-03 14:29:58
It took four years of consultation between a university archivist and a federal agency to get things started, but eventually a new and important collaborative project was born: the digital preservation of more than 1,700 glass plate negative images on the construction and history of the Soo Locks at Sault Ste. Marie in Michigan’s Upper Peninsula. These images are not only preserved for the future, but freely available to the public, thanks to the staff at the Clarke Historical Library at Central Michigan University and the US Army Corps of Engineers (USACE). Making Shipping Easy The Soo Locks were built on the St. Marys River, an important shipping route along the Great Lakes. Before the Locks, however, shipping between Lake Superior and Lake Huron was near impossible because of an abrupt twenty-one foot drop in the river at Sault Ste. Marie. Goods could be portaged around the rapids, but this was slow and expensive—in 1845, that one-mile portage accounted for twelve percent of the shipping costs for the 750-mile journey from Marquette, Michigan, to Buffalo, New York. In 1855 engineers opened the first modern lock at the Soo, and in 1881 the USACE took over operation. Since then, bigger and bigger ships have navigated easily through the St. Marys River. Today the complex consists of four locks, two of which operate regularly. The Locks are both a US Department of Homeland Security site as well as a National Historic Landmark. The economic impact of this engineering feat cannot be understated. Each year, more than 7,000 ships carrying 70 million tons of freight (mostly iron down from Minnesota and coal up to the northern Great Lakes and Canada) pass through the Locks. According to Homeland Security, a six-month closure of the Locks would result in losses of 11 million jobs and $1 trillion to the US economy. The Photographic Record Engineers at the Soo have meticulously maintained records. This includes more than 1,700 photographs taken circa 1885 to 1941 documenting the construction and operation of three of the locks as well as other USACE endeavors to enable safe navigation of—and even the occasional accident on—the St. Marys River. For years, the glass and nitrate photographic negatives were stored in a filing cabinet in the Soo Locks Administration Building. Each negative was stored in a manila mailing envelope marked with a unique image ID. Though originally a handwritten log documented each photograph’s ID number, date, and description, staff later produced a typed copy. As with any large set of fragile historical records with a history of limited preservation efforts, 2.75 percent of negatives were lost while another 2.25 percent sustained damage beyond a chipped corner. Remarkably, 95 percent of the images survived in good condition. For more than four years, Frank Boles, director of the Clarke Historical Library, consulted with Soo Locks staff about the organization and preservation of their historical documents. As a result, USACE hired a dedicated archivist to assist with preserving its vast amount of records. Among the most pressing concerns cited by Boles, both in terms of preservation and potential use, were the 1,700+ glass plate negatives. In the fall of 2015, USACE contracted the Clarke to digitize the negatives and rehouse them in archival storage. A Monumental Undertaking Security concerns required all scanning to take place within the Soo Locks Administration Building. USACE supplied space and power while the Clarke staff brought the necessary scanning equipment. The USACE contract required scans to be digitized at an unusually high 1200 dpi resolution, so we tested our Epson XL 11000 scanners at that standard. The average time to scan an 8" x 10" negative took four to five minutes. We concluded that we’d need 200 hours to complete this portion of the project. To finish the work in a single visit, we used three scanners, each set up with an assigned letter (A, B, and C), which became the prefix of an arbitrary identifier for each file. We could then rename the files with the USACE image ID at a later date. Although this process required a great deal of organization and careful attention, it was far less resource-intensive than assigning all metadata onsite, thus shortening the time needed at the Locks. With three scanners, we scanned at a rate of 250 to 300 per day, which included several oversized plates scanned in two parts and digitally stitched together later as well as several shattered negatives that required jigsaw puzzle skills to piece together on the scanner bed. Back at the Clarke, we renamed the files, produced preservation copies, and touched-up 300 dpi derivatives. The negatives are now housed in the Still Picture Unit of the National Archives and Records Administration in College Park, Maryland. Reaching The Public Security concerns prohibit USACE from making a publicly accessible website for displaying the images. When the Clarke expressed an intention to create such a site, we learned that obligations embedded in standard military contracts did not allow contractors to retain scans until we submitted a Freedom of Information Act request. While waiting for the request to be processed, Clarke staff developed an interface to display low-resolution copies of the photos on our website. Once we received images back from USACE, we quickly processed them for web display and added a watermark. The final product, revealed in October 2016, is a publicly-accessible keyword and date searchable database of the Soo Locks’ history, found at http://clarke.cmich.edu/SooLocks. Through the partnership of an academic special collections library and a federal agency, the best visual record of one of the nation’s most important engineering endeavors has been made digitally accessible for researchers, educators, hobbyists, and anyone with an interest in the history of the Soo Locks.
Published by Society of American Archivists. View All Articles.