As part of the Downtown Visioning Study and Tunnel Project, the City's consultant has completed a structural review of the existing tunnel and City staff are regularly monitoring its condition for any signs of continued deterioration. As a result of the structural review and monitoring, the consultant has prepared conceptual plans for possible Interim Repairs to keep the tunnel structure itself, and the pedestrian and parking areas above, in a safe and usable condition until final decisions with respect to the tunnel are made.
Diagrams, Estimates, Alternative Scenarios
In conjunction with the various Vision Alternatives that have been prepared based on community input thus far, the consultant has also prepared conceptual Plan and Section diagrams of the tunnel along with Conceptual Cost Estimates for the different tunnel scenarios.
As a reminder, Alternative A envisions the complete repair and reuse of the tunnel for pedestrian and bicyclist mobility with parking and the pedestrian mall above.
Alternative A-1 also envisions the repair and reuse of the tunnel, but provides for portions of the roof deck to remain open for lighting, security, and as a point of interest.
Alternative B envisions that at least a portion of the tunnel structure beneath the parking lot would be filled in, thereby closing off the tunnel to through movement.
Alternative C proposes the complete removal of the tunnel structure and its replacement with a new roadway connection from Flynn Street to Hanover Street. Cost estimates associated with Alternative C include additional work on Hanover Street that would be necessary to accommodate the new roadway.