Survey Number:
HPS-226
Year
Built: 1931
Architectural Style:
Reinforced Concrete Arched Bridge
THEME / CONTEXT
The Tempe (Old Mill Avenue) Bridge is associated with the context of Community
Planning and Development. It falls under the theme of transportation - bridge.
HISTORIC ASSOCIATION
The Tempe (Old Mill Avenue) Bridge is among the oldest automobile crossings on
the Salt River in the Phoenix metropolitan area, and has been in continuous use
since its completion in 1931. It was the major transportation link in three
transcontinental highways (U.S. Routes 60, 70, and 80) and Arizona’s only
north-south route, U.S. Route 89, until the freeway system was begun in the
1950s.
ARCHITECTURAL
ASSOCIATION
The Tempe (Old Mill Avenue) Bridge is
significant for both its method of construction and its artistry of design. The
bridge is a ten-span poured concrete, open spandrel structure. The spans are
multiple ribbed with open spandrels, each 140 ft. long, supporting a concrete
roadway on beamed and webbed columns above the ribs. The ribs are designed as
hingeless arches fixed at the piers.
SUMMARY
The Mill Avenue Bridge is the second oldest automobile crossing on the Salt
River in the Phoenix metropolitan area, and has been in continuous use since its
completion in 1931. It was the major transportation link in three
transcontinental highways (U.S. Routes 60, 70, and 80) and Arizona’s only
north-south route, U.S. Route 89, until the freeway system was begun in the
1950s. The bridge was built to replace an earlier highway bridge built twenty
years earlier at Ash Avenue but had become increasingly congested and was no
longer able to adequately support wider and heavier vehicles. In 1928, a group
of Tempe businessmen submitted a request to the Arizona Highway Commission that
a new bridge be planned. The bridge was designed by the Arizona Highway
Department in 1929. Ralph Hoffman, the bridge engineer for the State of Arizona,
signed the contract with Lynch-Cannon Construction Company of Los Angeles,
implementing Federal Project 2-B. The bridge was opened to traffic in August of
1931, but was not officially dedicated until 1933. Presiding at the ceremony
was Arizona Governor B. B. Moeur, a Tempe physician.
The Mill Avenue Bridge is a
ten-span poured concrete, open spandrel structure. The spans are multiple
ribbed with open spandrels, each 140 ft. long, supporting a concrete roadway on
beamed and webbed columns above the ribs. The ribs are designed as hingeless
arches fixed at the piers. Two types of piers are used in the design and the
spans are divided into groups of three, four, and three, separated by abutment
piers. Abutment piers are of a typical column construction. Abutment piers are
extended and carried above the roadway level in four hexagonal towers forming
pedestrian rest bays with canopies. This effect is maintained with hexagonal
pylons terminating the railings at each end of the bridge.
SOURCES
Tempe 1997 Multiple
Resource Area Update
Tempe Historic Property Survey HPS-226 Mill Avenue Bridge
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