Financing Mechanisms for Capacity Improvements at Interchanges

ODOT uses various planning tools to manage the capacity and maintain the safety of state facilities. These tools include the ODOT Access Management Program, local government Transportation System Plans (TSPs), Transportation Planning Rule review, and Interchange Area Management Plans (IAMPs). These tools provide a framework for ODOT to work with local governments when their actions potentially affect the performance of state facilities. Over time, for example, development pressures around state facilities eventually result in the need to increase capacity and the need to finance that increased capacity. Comprehensive plan and zoning map amendments set the stage for future transportation impacts,…

ODOT uses various planning tools to manage the capacity and maintain the safety of state facilities.  These tools include the ODOT Access Management Program, local government Transportation System Plans (TSPs), Transportation Planning Rule review, and Interchange Area Management Plans (IAMPs).  These tools provide a framework for ODOT to work with local governments when their actions potentially affect the performance of state facilities.  Over time, for example, development pressures around state facilities eventually result in the need to increase capacity and the need to finance that increased capacity.  Comprehensive plan and zoning map amendments set the stage for future transportation impacts, exceeding the capacity of the future planned transportation system. 

In the case of interchanges, research has shown that the traffic impacts of upzoning can be significant.  A recent Portland State University study examined the effects of comprehensive plan amendments on interchange performance on the Oregon highway system.  Plan amendments were found to have a substantial effect on rural interchange ADT, but their incidence was very limited.  In urban core areas, the estimated effect of plan amendments was negligible, possibly due to interchange congestion or more effective land use planning.  In urban fringe areas, plan amendments were estimated to account for about 5 percent of the subsequent interchange ADT, equivalent to about two years of the design life of these facilities.

To date, about seven Interchange Area Management Plans are in place and several more are in process.  In the future, as the pressure for new development increases, local governments will likely need to consider ways to fund needed infrastructure expansion in interchange areas if IAMPs are to be amended.

The ODOT Planning Section has done a considerable amount of work on developing basic protocols for staff to use during the negotiation of fair, legally defensible and enforceable mitigation agreements with local governments and/or private developers during the development review process.  “Chapter 5: Negotiated Mitigation Agreements” in ODOT’s Development Review Guidelines was recently completed to support staff understanding of the opportunities and limitations that apply when negotiating such agreements, and to understand the legal framework within which the Agency may negotiate agreements for mitigation by developers and in cooperation with local governments.  While this work lays out the existing framework under which mitigation agreements may be pursued, appropriate mechanisms for financing capacity improvements at interchanges have not been investigated.  This research project would explore the financing tools available for local governments to use.  Without clearly identified means to finance needed capacity improvements, ODOT planning tools are limited in their effectiveness.