Economic impact of closing low-volume rural bridges.

The State of Kansas has approximately 25,464 bridges that are located on the state, county and
city roadway network. As the infrastructure in Kansas ages, bridges can become structurally
deficient or functionally obsolete. The Kansas Department of Transportation (KDOT) defines
a bridge as structurally deficient if an inspector determines the bridge deck, superstructure
substructure, culverts and retaining walls are not able to support today’s federal legal
loads (KDOT, 2008). A bridge that is defined as functionally obsolete consists of design
characteristics, which could include narrow width, inadequate clearance beneath, condition
of the structure, or deficient approaching roadway alignment (KDOT, 2008). Limited research
has been performed that specifically investigates advantages and/or disadvantages of closing
a bridge on a rural low volume road. The objective of this research project was to determine
a cost comparison of replacing and/or repairing a rural low volume structurally deficient
bridge, versus closing the same bridge and finding the change in vehicle operating cost based
on the proposed driver detour.