Project Number: 3318-01
From milepost 0 to milepost 0.1
RATA Funds: $193,300
Legislative District: 7
Status: Construction
Date Approved: 2018
BRIDGE BACKGROUND
The Arden Bridge superstructure was constructed in 1969 and consists of variable depth plate
girders manufactured by Spokane Culvert. The girders are supported on concrete foundations
that were existing to the site. The deck consists of 2 inch deep corrugated steel bridge decking
with an asphalt overlay. The 60 foot bridge carries two lanes of traffic and has a large skew (56
degrees) due to the curved alignment of the Little Pend Oreille River through the bridge
opening. Current ADT is 889. The road carries local and truck traffic, including logging trucks.
Due to a high skew, the bridge is undergoing rotational movements that have caused several
issues, including a serious condition at the substructure. Bridge movement has caused
abutment spalling at the acute bridge corners, including a large spall and loss of bearing
support at the northeast corner leaving exterior Girder A nearly unsupported. A repair has
been designed and will be installed by the County in Spring 2017, but is only considered a
temporary measure until the bridge can be replaced.
Additional deterioration issues include:
? Exposed footings and scour along the southeast corner of bridge
? Missing or failed end diaphragms causing sloughing of approach material
? Cracking and failure of ACP pavement
? Corrosion of steel decking
REPLACEMENT CONCEPT
Due to issues with all elements of the bridge, a total replacement is warranted. The concept is
to replace the bridge along the same straight alignment with a longer, single span bridge
(approximately 110 feet long) with a reduced skew angle. Prestressed concrete girders with a
cast-in-place deck for durability are planned. Pile foundations are anticipated and will prevent
potential scour issues. Channel protection will be designed to protect embankments due to
stream alignment.