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Granitoid

6/4/2010:

North Dakota's weather is brutal for street pavements. Freezing and thawing and heat waves combine with heavy traffic to crumble even the strongest tar or concrete streets or highways. As automobile traffic increased from 1900 to 1910, the city of Grand Forks experimented with various paving materials as motorists demanded better roads, trying "tar" and "bitumen" and "asphalt" and "granitoid" in 1910. The Granitoid pavement put in place in three paving districts in Grand Forks in 1910 (and 1911) still endures, one hundred years later. Most streets and highways last for twenty years, at most.

Granitoid, a patented road material, was a mix of crushed granite and concrete, providing a hard surface for auto traffic. Grooves in a gridiron pattern also gave good footing for horses' hooves. It looked like a red brick street because of the red color of the granite, but it was a solid layer of concrete. The granite screenings, or chips, came from upper Michigan.

Granitoid pavement resisted frost-heaving damage because it had been laid over a deep bed of gravel and sand. Contractors poured the Granitoid pavement in a unique arched crown to make it extremely strong and long-lasting. A Chicago inventor named R.S. Blome received a patent for his distinctively-named Granitoid pavement on June 4, 1907. Over thirty cities in the U.S. and Canada installed Granitoid from 1907 to 1912, but eventually, it faded from use because of the high cost of the granite chips.

Through the years, it proved to be durable, yet it was "slightly more noisy than some other paving," when automobile tires moved swiftly over the grooves in its surface. Eventually, after decades of use, the pavement became "distressed and patched at some locations due to underground [repair] work done . . . by the city."

In 1992, the Granitoid streets of Grand Forks gained a listing on the National Register of Historic Places, but not without controversy. The city street department found the surface difficult to match with a concrete patch and motorists had to slow down because of its bumpiness. Local citizens Clyde and Sally Morris wrote up the nomination and, eventually, city and state and national officials approved it.

Thus, Granitoid paving joined Route 66 and a 1929 Arkansas concrete highway as the only pavements on the National Register. Preservation of the Granitoid streets became especially difficult when the Great Red River Flood of 1997 engulfed Grand Forks. Some pavement was destroyed by heavy equipment used to build clay dikes and some streets were replaced by permanent floodwalls.

Still, some of the pavement remains in 2010, one hundred years after its installation. The city also keeps four-foot-by-four-foot sections of the Granitoid in permanent storage.

On some streets, tiny bronze plates, embedded in the pavement, identified the surface as "R.S. Blome Co., Granitoid Pavement, Pat'd June 4, 1907."

How much longer can Granitoid exist? Well, it has lasted for one hundred years; maybe it can go another decade or two.

Dakota Datebook written by Dr. Steve Hoffbeck, History Department, Minnesota State University Moorhead

Sources: Paving Meeting is Interesting," Grand Forks Daily Herald, June 10, 1910, p. 6;

"City Council Held Important Meeting," Grand Forks Daily Herald, March 8, 1910, p. 6;

"Start Paving In Ten Days," Grand Forks Daily Herald, April 20, 1911, p. 6;

"Begins Paving Today," Grand Forks Daily Herald, May 7, 1911, p. 1;

"What's The Fuss About Granitoid?, Grand Forks Herald, November 29, 1990, p. 1C;

"Historic Pavement Being Preserved," Grand Forks Herald, November 5, 2004; U.S. Patent Office, "William A. Sinek and Rudolph S. Blome, of Chicago, Illinois, Pavement and Method of Making the Same," No. 856,105, Patented June 4, 1907; Nomination of the R. S. Blome Granitoid Pavement in Grand Forks North Dakota, to the National Register of Historic Places, July 28, 1990.