Cedar Hill Bridge, one of the oldest and most historically intriguing bridges in New Mexico, is slated for a renovation this spring. San Juan County announced that $600,000 of county capital reserves will fund the project.
Located in Cedar Hill, east of Aztec, the bridge was built in 1913, according to San Juan Historical Society. It crosses the Animas River and connects County Road 2380. Once the project is complete, the bridge will become part of a 2-mile walking trail along the river.
San Juan County spokesman Devin Neeley said the project was awarded to TRC Construction Inc. of Flora Vista at the Feb. 21 San Juan County Commission meeting for $611,333.35.
According to the Historic Bridges website, the bridge “is remarkable for the lack of rust-related deterioration of its steel materials.” Despite its remarkable good condition, it is in need of structural repair.
“The Cedar Hill Bridge is an extremely rare surviving example of a pin‐connected highway truss bridge in New Mexico,” according to Bach Steel’s scope of work and repair estimate.
Renovations will include work to straighten beams and trusses and to check connections, according to Neeley. The two-phase project will begin with repairs to both abutments, followed by repair work to the actual bridge during the second phase.
“We believe that this is the oldest bridge in San Juan County and was constructed shortly after New Mexico’s statehood,” Neeley stated in an email. He added that their understanding is that “the bridge itself was purchased out of a mail-order catalog.”
On the Historic Bridge website, it states that the builder of the bridge is not known, but was reportedly “constructed shortly after floods in 1911 devastated area bridges.”
“The rolled channels display ‘Illinois 2.’” The “Illinois” refers to Illinois Steel, which had become part of U.S. Steel in 1904. Until the 1950s, U.S. Steel continued to roll steel bearing the former company name of the mill that rolled the steel, the website states.
More specific details are mentioned including, “most steel with ‘Illinois’ was followed by a ‘G’ or ‘S’ (referring to respectively to the Gary, Indiana, Works and the South Chicago Works).” The use of the “2” is rare, and its meaning is unclear, but it might refer to a specific steel mill.
“Cedar Hill Bridge is remarkable for its lack of deterioration,” Bach Steel said. “Its rural location, and perhaps even the dry climate of the area have allowed much of this truss to remain in nearly like‐new condition.”
Lack of de-icing salts and chemicals might also have contributed to its good condition.
The bridge appears to have never been painted, indicating that it avoided deterioration by virtue of its location and material properties alone.
When the bridge was erected, mill scale survived on the bridge and, in a number of areas, this mill scale remains visible.
Mill scale is a type of iron oxide that is formed on the surface of the steel during the hot-rolling process. The very high surface temperature combined with high roller pressures result in a smooth, bluish-gray surface.
“Typically, if a bridge was erected over 100 years ago and it had mill scale on it when erected, one would expect that time and weather would have removed all traces of it by today, which is what makes the Cedar Hill Bridge remarkable,” the Historic Bridge website stated.
The bridge’s “unusual lack of deterioration also manifests itself in the sharp edges of all the steel on the bridge which have not worn down, and the easily legible steel mill name on the channels.”
Even the floor beams of the bridge have hand-painted part and job numbers on them, which appear to date to the original fabrication and erection of the bridge.
San Juan County Public Works Director Nick Porell told KOB TV, there aren’t many bridges in the country that are 110 years old.
He said the bridge was, “purchased from a catalog. I guess at the time you could purchase a bridge from the Montgomery Ward Catalog.”
According to San Juan County Historical Society, the Cedar Hill Bridge Co. was awarded the contract to install the bridge in November 1913 at a cost of $2,000.
The bridge was closed to vehicle traffic in the 1990s, but it remained open to pedestrian traffic until 2017, when it was determined to be too dangerous.
The bridge, used originally by stagecoaches and later vehicles, could reopen as soon as this summer, depending on the weather, Porell said.
This article was republished to add a photo of the correct bridge.