Skip to main content

Bridge Monday; Old US 80 on the Gillespie Dam Bridge

Back in 2012 I visited the Gillespie Dam Bridge located southwest of Phoenix in rural Maricopa County along the Gila River.


The Gillespie Dam Bridge is a truss bridge located directly south of the failed 1921 Gillespie Dam on the Gila River.  The Gillespie Dam Bridge was completed in August of 1927 and was part of early US Route 80.  The Gillespie Dam Bridge is 1,662 feet long, has a road deck 25 feet wide, has 9 spans, and 8 pilings in the Gila River Bed.  The Gillespie Dam Bridge saw service on US Route 80 until the highway was shifted eastward in 1956 to the current Arizona State Route 85 corridor.

The Gillespie Dam Bridge actually survived a breach of it's namesake dam.  The Gillespie Dam is a 1,700 foot wide concrete arch structure which was completed in 1921 as stated above.  The Gillespie Dam was originally designed for cars to travel over, but with the spill-over design it meant that it couldn't be crossed when the reservoir topped out.  The Gillespie Dam was part of the original alignment of US Route 80 but only for a brief period of time.  In 1993 record winter flooding on the Salt River and Gila River caused a 120 foot section of the Gillespie Dam to fail which can be seen from the Gillespie Dam Bridge.



The Gillespie Dam replaced the earlier Auto Trail span located northeast of Wellton in Yuma County which was called the Antelope Hill Bridge.  The Antelope Hill Bridge was a wooden structure that was completed in 1915 over the Gila River.  The Antelope Hill Bridge carried the; Old Spanish Trail, Dixie Overland Trail, Southern National Highway, and Bankhead Highway over the Gila River from 1914 until the Gillespie Dam replaced it in 1921.  The original route from Yuma to Phoenix went through the communities of; Dome, Wellton (over to the north bank of the Gila River on the Antelope Hill Bridge), Palomas, Aqua Caliente, Arlington, and Buckeye.  The new route (which eventually became US 80) over the Gila River at the Gillespie Dam ultimately diverged in Wellton continuing on the south bank through the communities of; Stoval, Sentinel, and Gila Bend.  This 1924 Four Corners Area Auto Trail Maps shows both the Antelope Hill Route and Gillespie Dam Route over the Gila River.

Four Corners Auto Trail Map 

This 1927 highway map of Arizona shows the original routing of US 80.  It is unclear if the alignment if over the Gillespie Dam or Gillespie Dam Bridge.

1927 Arizona State Highway Map

This 1956 Arizona State Highway Map shows the shift of US 80 east to the AZ 85 corridor.

1956 Arizona State Highway Map


Comments

Popular posts from this blog

The Bayshore Freeway (US Route 101)

The Bayshore Freeway is a 56.4-mile component of US Route 101 located in the San Francisco Bay Area.  The Bayshore Freeway connects the southern extent of San Jose to the Central Freeway in the city of San Francisco.  The corridor was originally developed as the Bayshore Highway between 1923 and 1937.  The Bayshore Highway would serve briefly as mainline US Route 101 before being reassigned as US Route 101 Bypass in 1938.  Conceptually the designs for the Bayshore Freeway originated in 1940 but construction would be delayed until 1947.  The Bayshore Freeway was completed by 1962 and became mainline US Route 101 during June 1963.   Part 1; the history of the Bayshore Freeway Prior the creation of the Bayshore Highway corridor the most commonly used highway between San Jose and San Francisco was El Camino Real (alternatively known as Peninsula Highway).  The  American El Camino Real  began as an early example of a signed as an Auto Trail starting in 1906.  The era of State Highway Mainte

Former US Route 101 and California State Route 41 through Paso Robles

Paso Robles is a city located on the Salinas River of San Luis Obispo County, California.  As originally configured the surface alignments of US Route 101 and California State Route 41 converged in downtown Paso Robles.  US Route 101 originally was aligned through Paso Robles via Spring Street.  California State Route 41 entered the City of Paso Robles via Union Road and 13th Street where it intersected US Route 101 at Spring Street.  US Route 101 and California State Route 41 departed Paso Robles southbound via a multiplex which split near Templeton.   Pictured above is the cover of the September/October 1957 California Highways & Public Works which features construction of the Paso Robles Bypass.  Pictured below is the 1935 Division of Highways Map of San Luis Obispo County which depicts US Route 101 and California State Route 41 intersecting in downtown Paso Robles.   Part 1; the history of US Route 101 and California State Route 41 in Paso Robles Paso Robles ("Pass of the

Paper Highways; US Route 20 Alternate over Teton Pass

The 8,431-foot-high Teton Pass lies in the Teton Range of the Rocky Mountains within Teton County, Wyoming.  Presently Teton Pass is crossed by Wyoming Highway 22 and Idaho State Highway 33.  At one point the highway over Teton Pass was signed as US Route 20 Alternate.  US Route 20 Alternate was over Teton Pass never formally approved by the American Association of State Highway Officials nor has the corridor ever been officially part of a US Route.  The image above was taken from the 1949 Rand McNally Map of Idaho, Wyoming and Montana which shows US Route 20 Alternate branching from US Route 20/US Route 191 near Sugar City, Idaho and crossing Teton Pass towards Jackson, Wyoming.   Part 1; the history of US Route 20 Alternate over Teton Pass No major Auto Trail was ever assigned to Teton Pass as evidenced by the 1925 Rand McNally Map of Idaho, Montana and Wyoming .  On the Wyoming side Teton Pass can be seen as part of Wyoming Highway 25 ("WY 25") whereas no State Highway is