The State Highway Department has, during the period covered by this
report, prepared designs for ninety-six bridges and fourteen special
culverts. Of these structures sixty bridges and ten culverts have been
constructed at a total cost to State and Counties of $617,388.09.
The structures paid for out of State funds consist of twenty-two
reinforced concrete bridges, ten wood bridges, and seven culverts. The
total expenditure of State funds for these bridges and culverts was
$239,044.85.
[Illustration: REINFORCED CONCRETE BRIDGE OVER HOOD RIVER, NEARING
COMPLETION, ON THE COLUMBIA RIVER HIGHWAY AT HOOD RIVER CITY. BUILT IN
1918.]
The structures paid for out of county funds consist of thirteen
reinforced concrete bridges, fourteen wood and steel bridges, and four
culverts; the total cost of these structures being $378,343.24.
Of the structures paid for by the counties, the State Highway Department
supervised the construction for three reinforced concrete bridges, four
steel and wood bridges, and one culvert; the cost of which totaled
$288,743.24.
A complete tabulation of the bridges designed and constructed is given
in another part of this report, and complete descriptions of the more
important structures will be found in the articles devoted to the
particular counties in which the structures are located.
The $250,000.00 intercounty bridge across the Willamette River at Salem
was completed, and has attracted more than local attention. While the
cost of this structure was borne by Marion and Polk Counties the design
and construction engineering were handled by this Department.
The reinforced concrete arch bridge at Hood River, the largest concrete
bridge yet constructed in this State was designed and built under State
supervision, although the County also contributed toward its cost.
Among the proposed bridges of considerable magnitude for which county
officials have requested designs from this Department may be mentioned
the Deschutes and Oregon City. The former will be located between the
present toll bridge and the railroad bridge across the Deschutes River
and will thus obviate the necessity of toll payments. It will consist of
a series of reinforced concrete arches. The Oregon City bridge will
replace the old suspension bridge across the Willamette. Studies are
being made and comparisons of various types of bridges and locations of
site are being made.
During the war period, both for patriotic and economic reasons the
employment of steel bridges was discontinued and wooden truss bridges
used instead. Now that the demand for steel for war purposes has
subsided, and there are indications of a decline in the price of
structural steel in the near future, the resumption of use of that
material in the construction of bridges will probably be more general.