The Interstate Bridge Replacement project, spanning Oregon and Washington, is set to meet its $1.5 billion revenue target through tolling, despite an anticipated drop in traffic. The study, presented at a joint meeting of the Oregon and Washington State transportation commissions, indicates a potential loss of about a third of current traffic on the bridge.

Financial Strategies and Challenges

The consulting firm Stantec conducted the Level 3 Traffic and Revenue study, which examined four toll rate scenarios. These scenarios range from $1.55 to $4.70, depending on the time of day. The tolls are expected to generate revenue primarily through toll-backed bonds or a federal TIFIA loan, if approved.

The project’s financial plan originally anticipated toll contributions of $1.2 billion, but the updated estimate of $1.5 billion is crucial as the project’s cost has ballooned from $6 billion to $14.4 billion. The project includes replacing the twin bridges over the Columbia River, extending light rail to Vancouver, and rebuilding several I-5 interchanges.

Project Phases and Funding

After the cost increase, state leaders have urged a focus on core components, such as the main twin bridges and necessary ramps, estimated at $7.65 billion. The first phase, excluding the light rail extension, is estimated at $5.68 billion, with current funding just covering this cost.

Traffic diversion remains a concern, with potential shifts to the nearby Interstate 205 Glenn Jackson Bridge. The study suggests a significant initial diversion, although traffic levels are expected to recover by 2050.

Washington State Treasurer’s office confirmed that the toll revenue would suffice to meet the $1.5 billion goal, though the financial strategy involves careful management of bonds and potential federal loans.

Original reporting: KGW Portland — read the source article.