Category Archives: Roads

Finding Old Highways – A Guide – Part 2

Concrete Paving

Concrete is a very durable material. It has many uses, though for our purposes – roadway surfaces, curbs, and sidewalks. Local roadways, such as concrete city streets, won’t be covered in this post. Bridges will be covered in a later post. This durability allows us to get either a relative date of when a roadway was paved or built to an absolute date when we find a date stamp.

  • Style of Paving
Short section of Roberts Rd that is now a driveway.
Short section of Roberts Rd that is now a driveway.
1920's paving near Osborne St. Note the widening work that was done on the right side. Looking west.
1920’s paving near Osborne St. Note the widening work that was done on the right side. Looking west.

As technology has evolved, so has concrete paving. The first concrete paving along State Highways was 10-12′ wide, usually not reinforced with steel. These roads were paved in one single slab of concrete. Roadways of this style were paved from around 1910 to 1915. After 1915, wider paving was used and was generally reinforced. Wider paving ran from 15′, 18′, and a “full” 20′. These are usually referred to as “Single Slab Paving”.

Sometime around 1923, longitudinal joints were added to the concrete paving. This created a “Twin Slab” roadway. This style persists today, though greatly changed. Early Twin Slab roadways had fewer expansion joints running across the lane. After around 1926, this problem was worked out by adding more frequent joints. By this time, each lane was a “standard” 10′. This standard remained until the late 1940’s when lane width started to widen to 12′.

  • Date Stamps
1948 date stamp on Olympic Blvd.
1948 date stamp on Olympic Blvd.

Contractors, either by requirement or pride, usually stamp the concrete roadway, curb, or sidewalk with a date stamp. These stamps vary in location, size, and information. Date stamps marked either the beginning or end of a days paving. As such, the stamp tended to be located near an expansion joint. A general rule with date stamps is “find one, you can find the rest”. This is mostly about the location. Some stamps are in the middle of a lane, some are to the side of a lane. The orientation also varies with stamps. The information contained in these stamps also varies. Early stamps just have the contractor and the date. Later stamps added the engineering station. Without going into too much detail, at this time, about engineering stations, the “zero” point is at the beginning of a road section or project. With little exception, I have had little success in finding a date stamp on Single Slab roadways. Twin Slab roadways are much better with stamps.

Using date stamps and styles as a guide, you can easily date a roadways construction to within a few years. There are other methods you can use, but these aren’t covered here. Some will be covered in later posts. Stay tuned for more posts. Bridges, Road Signs, and more will be covered in the future. If you have any questions, please post a comment or send me a message.

Image of the Week – 4/5/15

Tunnels 2 and 3 in Wheeler Gorge on State 33 near Ojai, CA.
Tunnels 2 and 3 in Wheeler Gorge on State 33 near Ojai, CA. Built in 1931.

Image of the Week – 3/15/15

Interstate 5 under construction at Magic Mountain Parkway in 1964.
Interstate 5 under construction at Magic Mountain Parkway and the Santa Clara River in 1964. Old US 99 is visible on the right side.

Image of the Week – 3/9/15

St. Francis Dam site in 2006 from the reservoir side. The crumbling remains of the wing dam are visible on the ridge to the right.
St. Francis Dam site in 2006 from the reservoir side. The crumbling remains of the wing dam are visible on the ridge to the right.

March 12, 2015 will mark the 87th anniversary of the collapse of the St Francis Dam in San Francisquito Canyon, Los Angeles County, California. The collapse occurred just before midnight on March 12, 1928. It is still California’s second largest disaster in terms of lives lost. Approximately 500 people died in the ensuing flood which flowed to the ocean near Oxnard, CA along the Santa Clara River Valley. Only the 1906 San Francisco Earthquake and Fire exceeds the number.

Image of the Week – 3/2/15

Burro on the Trona-Wildrose Road on the descent into Panamint Valley in February 2006.
Burro on the Trona-Wildrose Road on the descent into Panamint Valley in February 2006.

Image of the Week – 2/23/15

I-5 and State 110 Interchange in 1962, looking northerly along the Arroyo Seco Parkway (State 110, then  US 66).
I-5 and State 110 Interchange in 1962, looking northerly along the Arroyo Seco Parkway (State 110, then US 66).

Image of the Week – 2/16/15

Mt Baldy Road, Lower Tunnel. Built in 1949.
Mt Baldy Road, Lower Tunnel. Built in 1949.

Victoria Bridge in Riverside, CA

Built in 1928, the Victoria Bridge crosses the Tequesquite Arroyo in style. This bridge was built to carry streetcars on Victoria Avenue across the arroyo as well as auto and horse carriage traffic. It is a rare example in Southern California of an arch bridge of this magnitude crossing a generally dry location. The deck and railing were restored in the early 2000’s to their original 1920’s appearance.

Victoria Avenue in the Riverside area itself is a rather beautiful roadway to travel. It was constructed in the early 1900’s as such a roadway and retains most of the original features today, south of this bridge. Quite a few miles of the roadway are comprised of a two-lane divided roadway surrounded by orange groves. These orange groves comprise some of the last remaining groves in Southern California. It is significant as the Riverside area was home to the original orange groves that were planted in the late 1800’s in Southern California.

Side view showing the multiple arch span.
Side view showing the multiple arch span.
Deck view with the restored railing and lighting.
Deck view with the restored railing and lighting.
New dedication plaque.
New dedication plaque.

Image of the Week – 12/26/14

Photo of the Week  – 12/26

City signage for former State 274 in the Clairemont area of San Diego.
City signage for former State 274 in the Clairemont area of San Diego.

Image of the Week – 12/21/14

Late 1950's view of the Santa Ana Freeway (I-5) at the Long Beach Freeway (I-710) with the original signage and route numbers.
Late 1950’s view of the Santa Ana Freeway (I-5) at the Long Beach Freeway (I-710) with the original signage and route numbers.