As the National Register of Historic Places has the responsibility of designating and protecting historic places that have played a significant role in American history, another organizational arm of the National Park Service is just as important but its role is different. Established in 1933 by Charles Peterson, the Historic American Builders Survey (HABS) had the responsibility of documenting and photographing countless historic buildings with the purpose of addressing their significance to the NPS and the state and local governments. Many of these buildings at that time were at risk of demolition in the name of progress. Civil Engineering works (like bridges and tunnels) and other mechanical artefacts were later added under the helm The Historic American Engineering Record (HAER), which was established in 1969. Eric DeLony was the director of that part of the organization from 1971 until 2003. The Historic American Landscapes Survey (HALS) was formed in 2000, focusing on landscapes and their historic features. But how does HABS/HAER/HALS work, especially when we look at historic bridges and ways to preserve them?
I had a chance to interview Christopher Marston (seen in the picture above), who has worked at this organization since 1989 and has focused on the infrastructural aspects of documenting and preserving history, esp. in terms of bridges. He provides us with an overview of the benefits and limitations of historic bridge preservation, including ways of educating the public. Here are his thoughts on the role of his organization and his work on historic bridges (feel free to click on the links to the bridges mentioned below):
- What is your favorite historic bridge (HB) in the US? The world?
Here are some of my favorites that I’ve seen in person, by type:
Wood Truss: West Union Bridge, IN by J.J. Daniels
Concrete Arch: Westinghouse Bridge, Pittsburgh
Stone-covered Concrete Arch: Boulder Bridge, DC
Suspension: Wheeling Suspension Bridge, WV
- What makes a bridge historic?
Older technology and craftsmanship. Continued use of original materials. Setting maintains its integrity.
- What is your role at HABS and HAER?
I’ve worked here for 27 years and am an architect and project leader. I started in 1989 when we had a field office in Homestead, PA. We started documenting the old Carnegie steel mills at Homestead and Duquesne. I documented my first bridge in 1991: Dunlap’s Creek Bridge, the 1839 cast-iron arch built for the National Road in Brownsville, PA. After moving to the DC office in 1994, I led teams documenting the Roads and Bridges in National Parks and Parkways: Colonial, Blue Ridge parkways, Skyline Drive. We also did several NY parkways: Bronx River, Henry Hudson, and Taconic State parkways. In 2009-2011, we recorded several large viaducts on the Western Maryland Railway, using a Leica laser scanner. In 2002, I was named the project leader for HAER’s involvement in the National Historic Covered Bridge Preservation Program. Since then we have recorded 88 bridges to HAER standards, put on a traveling exhibition with the Smithsonian, run two national conferences, done several in depth engineering studies, designated 5 National Historic Landmarks and nominated 2 others, and published Covered Bridges and the Birth of American Engineering in 2015. We are currently completing a second publication: Guidelines for Rehabilitating Historic Covered Bridges. See: https://www.nps.gov/hdp/project/coveredbridges/index.htm
- What is the difference between HABS/HAER and NRHP in terms of documenting and preserving HBs?
HABS/HAER works on in depth documentation of sites. In-house HAER projects are typically done to Level I standards: measured & interpretive drawings, large format photography, and a historical report. Mitigation projects are typically to Level II standards: large format photography, and a historical report only. NR does a contextual history and 35mm or digital photography, so is typically less in depth.
- What are the requirements for a HB to be listed on the National Register of Historic Places (NRHP)? And HABS/HAER?
HAER worked with state departments of transportation to develop and encourage bridge surveys beginning in the 1970s. Some were funded by the DOTs or FHWA or in partnership with universities. The first state bridge survey was in Virginia, beginning with the Humpback Covered Bridge, in 1970. http://www.loc.gov/pictures/collection/hh/item/va0239/
Between 1986 and 2000, HAER Chief Eric DeLony developed HAER state bridge surveys in partnership with DOTs, and hired summer teams of engineers, architects and historians to do comprehensive documentation projects. Notable examples include surveys done in Ohio, Wisconsin, Massachusetts, Arkansas, Oregon, Washington, Iowa, Texas, Pennsylvania, Missouri, Illinois, and California. Other significant projects that resulted in the documentation of hundreds of bridges include the FHWA-funded National Park Service Roads and Bridges Project, from 1988 to 2002. FHWA’s National Historic Covered Bridge Preservation Program resulted in HAER documentation of 88 bridges from 2002-2016, including several in-depth engineering projects. There are approximately 2,700 bridges listed in the HABS/HAER collection.
- If a HB is listed under the NRHP, how are they protected?
NR-eligible bridges trigger Section 106. In some cases, the bridge may be saved or moved. If demolition is necessary, 106 may trigger mitigation, which often leads to HAER Level II documentation. Since 1980, 100s of bridges have been documented through mitigation.
- How are the following HB types preserved mainly, in your opinion? An example of each is needed, more are welcomed.
Metal Truss: Vern Mesler’s Calhoun Bridge Park, MI ; Piano Bridge by Charles Walker, TX
Wood Truss: Gilpin’s Falls Covered Bridge, MD, by Tim Andrews of Barns and Bridges of New England. See attached case study.
Masonry Arch: Catoctin Aqueduct, C & O Canal NHP, MD, by McMullan & Associates. http://www.apti.org/clientuploads/publications/2015/SampleArticle_46.4_McMullan.pdf
- What problems have you encountered over the years regarding preservation policies on the federal, state and local levels?
Glulam is favored over solid timber in covered bridge rehab projects
AASHTO Standards often require too heavy a live load requirement unrealistic for historic bridges.
- What about as far as preserving practices?
Would prefer to see real rivets used over high strength bolts when possible. Vern Mesler’s program at Lansing Community College is teaching this practice through his Iron & Steel Preservation Conferences. The Piano Bridge in Texas was a nice exception in that hot riveting was used in the rehab. Unfortunately, TXDOT stopped requiring riveting after Charles Walker retired.
- And ownership of a HB?
States such as Vermont, Ohio, Indiana, among others, do an excellent job inventorying, rehabilitating, and maintaining historic bridges. Invest in inventory and management programs, etc.
- What measures are needed to better protect HBs from being altered or destroyed, in your opinion?
Continue to educate DOTs and especially SHPOs on best practices for rehabilitation.
- What HBs are being nominated today in comparison to 1970?
We still get a lot of bridges in the collection. HAER has documented several covered wooden bridges; Mead & Hunt is doing movable bridges in Louisiana, and did a bridge over the US/Mexico border; M&H and Berger teamed together to document 8 examples of common post-1945 bridge types.
I’m glad to see that bridges are getting nominated as National Historic Landmarks. Prior to 2010, there were only 11 bridges listed as NHLs: Eads, Bollman, Brooklyn, Casselman, Carrollton Viaduct, Thomas Viaduct, Old Blenheim (removed 2015), Covington-Cincinnati, S Bridge, Smithfield, Wheeling.
Since 2012, HAER has designated 5 bridges, and nominated 2 more: Powder Works, CA; Knight’s Ferry, CA; Brown Bridge, VT; Humpback, VA; Duck Creek Aqueduct, IN. Pending: Eldean, OH; West Union, IN. IN addition, the Edmund Pettis Bridge in Selma, AL was designated in 2013.
- What would Eric DeLony, the person who spearheaded the preservation of HBs in the 1970s and 80s say about America’s HBs these days?
I think Eric would be pleased with many of the successes in bridge preservation and documentation since he retired: The National Historic Covered Bridge Preservation Program, which he helped launch, has preserved over 200 covered bridges on top of the initiatives listed above; groups such as the Historic Bridge Foundation and historic bridge websites have proliferated, Vern Mesler’s Iron and Steel Conferences, and other preservation conferences continue to get the word out, and several important historic bridges have been preserved.
However, he would still troubled by the loss of bridges due to flooding, arson, neglect and detierioration. The lack of federal funding for preservation and documentation programs like those in the 1990s and 2000s is also alarming.
What was concluded in the interview? Preservation policies work when there is enough governmental support (including funding) to help document the structures and come up with ways to preserve them, ensuring that if possible, no mitigation is involved. However, private organizations and preservationists have stepped up in the efforts to better inform the public about ways of preserving historic bridges without having the excuse of “bridges meeting the end of their useful life” being used as justification for demolishing them. Many channels have been implemented to make preservation happen and keep history alive, whether it is through media outlets like this one or Preservation in Pink, advocacy groups, like Nathan Holth’s Historic Bridge.org, foundations like Historic Bridge Foundation, or even mechanics and steel welders who are doing the actual work, like Bach Steel, Workin Bridges, Mead and Hunt or even local bridge builders. We will be looking at these examples later on to show that while there is not much history left to save in the progressing mondernized society, there are plenty of historic works that need our attention, even if we turn to unexpected sources who have the same nostalgia as we do.
Special thanks to Christopher Marston for his help.
Note: A tribute to Eric will follow when the Ammann Awards are announced in January 2017. The Blenheim Covered Bridge, which was built in 1855, was destroyed by Tropical Storm Irene in 2011