Nintzel: Our tribute to Arizona bridges for Historic Bridges Month in November

Many of us who drive on the state highway system likely don’t pay much attention when we cross over the majority of the more than 4,800 bridges that the Arizona Department of Transportation maintains.

That’s in addition to thousands of other bridges on local roadways that belong to cities, counties and other entities.

There is, however, a special class of bridges that qualify as historic. November is Historic Bridges Month, so what better time than now to pay tribute to crossings that have played a significant role in Arizona’s history?

Bridges with names like Navajo (Marble Canyon), Ocean-to-Ocean (Yuma), Midgley (Sedona) and Salt River Canyon come to mind. While we can’t name all such structures, or all the people involved in the significant challenges of designing and building them, it’s possible to introduce you to one of our bridge pioneers in the Grand Canyon State.

His name is Ralph Hoffman. He served as state bridge engineer from 1923 to 1954, in the days when ADOT was the Arizona Highway Department. Mr. Hoffman’s family recently shared a reminder of his accomplishments.

Among the engineering triumphs that Ralph Hoffman planned and supervised the design of was the original Navajo Bridge at Marble Canyon, which the American Society of Civil Engineers noted that at the time of its construction in the late 1920s served “as the highest steel arch bridge in the United States” and for the next six-plus decades “served as the only crossing of the Colorado River for 600 miles.”

While ADOT opened a new Marble Canyon Bridge in 1995, Hoffman’s original bridge remains in place next to it, allowing visitors a chance to walk on it, take photos and enjoy the majesty of the canyon as well as this engineering feat. I can highly recommend it as one of Arizona’s sights to see.

Hoffman’s family also shared his quote from a 1934 “Arizona Highways” magazine article on bridges and beautification: “Finding that we cannot hide our structures in nature’s cloak, is it not better, therefore, to create a pleasing effect and develop some architecture into the structure. Plain surfaces are still desirable, but broken, occasionally, with a suggestion of light and shadow to relieve the monotony.”

Among the many other historic bridges Hoffman oversaw the design of were the original Mill Avenue Bridge over the Salt River in Tempe (1931) and the U.S. 60 Pinto Creek Bridge near Superior (1949). The latter reminds us that not all historic bridges are able remain in place. The Pinto Creek Bridge had served so many drivers well but time had taken its toll. With the recent opening of a new, modernized bridge, the old structure has been removed.

A plaque noting the historic structure is in place near the new Pinto Creek Bridge.

If you’d like to learn more about historic bridges, ADOT has its Arizona Historic Bridge Inventory Report on the agency’s website. It was initially published in 2008 for the National Register of Historic Places/Department of the Interior and was recently updated.

The report is very extensive, has more information about Ralph Hoffman and other Arizona bridge pioneers and includes great photos of a number of state and local historic bridges.

We’ll leave you with a quote from ADOT’s historic bridge report that caught my eye. “There can be little doubt that in many ways the story of bridge building is the story of civilization,” President Franklin Roosevelt stated in 1932. “By it we can readily measure an important part of a people’s progress.”

Editor’s note: Doug Nintzel is a spokesman for the Arizona Department of Transportation. Visit azdot.gov.