Bridge evolution was no cut-and dried process
October 12, 1995
By Pamela Cressey
The southern face of the Hooff's Run Bridge was constructed sometime between 1885 and 1895 for an additional railroad track out of red Seneca sandstone similar to Alexandria National Cemetery wall seen on far right.
Figuring out the date of material culture is a central part of archaeology. We are suppose to take all relevant data into consideration when arriving at a date for the beginning and ending manufacture of a ceramic plate, a pipe stem, a house foundation, or even a bridge. We are also surprised sometimes.
After a search through many old maps, photos and documents, I thought that we surely had figured out that a 16 foot wide red sandstone section was added in 1871 to the Orange and Alexandria Railroad (O&ARR) Bridge over Hooff's Run ( see last week's article). I soon found that more information would provide a different date.
As James Massey and Jere Gibber studied the evidence in order to write a nomination to the National Register of Historic Places, they arrived at a later construction date and discovered an intervening construction phase.
Part of our reasoning for the 1871 date had centered upon the 1877 map which showed two tracks on the bridge, rather than the original one. We looked for documentary evidence before 1877 that would show construction of the 16 foot addition to accommodate the second track. The 1871 date seemed to fit with the construction of the new Alexandria Cemetery wall which was made similarly. But Jim and Jere found that a second track was added over the 1856 grey stone bridge without expanding its 28 foot width. Then in 1872, a third track was constructed by the Baltimore and Potomac Railroad over a separate stone arch 42 feet north of the bridge. They found an the east abutment and one wing wall with two courses of the arch.
They deduced that the red stone span was the next construction phase (1885-1895) which widened the 1856 bridge to carry a fourth track. Lastly, a wooden trestle was built circa 1900-1905 between the first stone bridge and the second one to the north to carry a fifth track. Clues come from the disturbed masonry of the 1856 bridge face.
So what we originally thought was a two phase stone bridge building project, was actually four structures which carried five tracks over Hooff's Run. There is no evidence remaining of the original wood trestle which predated (1851-1856) any of the stone structures.
The 1885-1895 addition's red Seneca sandstone can now be seen as the southern face of the surviving stone railroad bridge. Jim and Jere write that the "addition was constructed at a time when massive stone arch railroad bridges and viaducts had once more come into prominent use after a period when iron construction was more common." The Virginia Midland Railroad, the heir of the O&ARR, eventually became Washington Southern Railway, and is today called Norfolk Southern.
Pamela Cressey is the Alexandria City Archaeologist.