Tunnel Solution

This plan is being developed by M Pauletto & Associates and PME Site Design Consultants. Once a sponsor is selected and invested into the project, the sponsor will own the plan and take the lead in having the plan accepted and approved, using a Design-Build-Finance-Operate and P3 (Private-Public-Partnership) delivery method.

· The existing I-5 Portland Vancouver Lift Bridge is to remain in service.

· Tunnel sections that are either “Bored” or “Open Cut” would be added to the existing freeway, highway, interchange, and road system.

· Approximate length of the tunnel: 7.85 Miles - 2 Sections = 3.51 Mile Bored + 4.34 Mile Open Cut

The Light Rail System is not part of this Alternative CIT Proprietary Plan, but the Light rail could be addressed and included separately at the discretion of the community and jurisdictional governments (please refer to “Item 5- Existing Bridge” below ). 

 The estimated bored section tunnel diameter would be 52-foot or 56-foot measured to the outside diameter. The "Open Cut Sections" width would be designed to match the bored sections and the lane transition requirements of the existing roads and infrastructure. 

The tunnel design has a total of 4 lanes - 2 in each direction. Alternatively, the 4 added lanes could be designated as “Commuter Lanes” for the morning rush hour (used exclusively for south travel) and for the afternoon rush hour (used exclusively for north travel). There would be two upper lanes and two lower lanes. As mentioned above, the lane directions could be designed to change for benefiting commuter traffic. All lanes could have a full 16-foot height; however, the design could be "downsized" and the two upper level or lower-level lanes could have a restricted 12-foot height if a smaller design diameter were to be utilized. 

 This design will leave the existing I-5 Portland Vancouver bridge which has 6 lanes of traffic (3 north bound & 3 south bound) alone - with no design upgrades, other than seismic enhancements or the possible addition of Light Rail with modifications and upgrades to the existing bridge. 

 The conceptual plan anticipates having emergency access points for the tunnel. 

 All lanes of traffic - 6 existing lanes and 4 new lanes in the tunnel (a total of 10 lanes) would be electronically tolled- no toll booths.